Medical treatment system and methods using a plurality of fluid lines.
Abstract
A medical treatment system, such as peritoneal dialysis system, may include control and other features to enhance patient comfort and ease of use. For example, a peritoneal dialysis system may include a control system that can adjust the volume of fluid infused into the peritoneal cavity to prevent the intraperitoneal fluid volume from exceeding a pre¬ determined amount. The control system can adjust by adding one or more therapy cycles, allowing for fill volumes during each cycle to be reduced. The control system may continue to allow the fluid to drain from the peritoneal cavity as completely as possible before starting the next therapy cycle. The control system may also adjust the dwell time of fluid within the peritoneal cavity during therapy cycles in order to complete a therapy within a scheduled time period. The cycler may also be configured to have a heater control system that monitors both the temperature of a heating tray and the temperature of a bag of dialysis fluid in order to bring the temperature of the dialysis fluid rapidly to a specified temperature, with minimal temperature overshoot.

Term
6.1 yearsleft in the term
Expires 2 November 2032.
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49 claims: 16 independent, 33 dependent
- 1NOVEDAD DE LA INVENCIÓN REIVINDICACIONES 1- Un sistema de diálisis que comprende:un casete de bombeo que tiene un cuerpo generalmente plano y una primera membrana flexible sobre un lado del casete suprayacente a una cámara de bomba sobre el casete;y un ciclador que tiene una superficie de control que incluye una segunda membrana flexible dispuesta para hacer contacto y acoplarse con la primera membrana flexible del casete de bombeo, el ciclador está dispuesto para mover una o más porciones de la segunda membrana flexible para mover al menos una porción de la primera membrana flexible suprayacente a la cámara de bombeo sobre el casete para causar flujo fluido en la cámara de bombeo, el ciclador adicionalmente incluye al menos un puerto en la superficie de control dispuesto para retirar fluido en un espacio entre la primera y segunda membranas flexibles una hacia la otra y para introducir fluido en el espacio para mover la primera y segunda membranas flexibles lejos una de la otra.
- 22,- El sistema de conformidad con la reivindicación 1, caracterizado además porque el al menos un puerto incluye un puerto de vacío dispuesto para retirar fluido selectivamente en el espacio entre la primera y segunda membranas flexibles, o introducir fluido en el espacio entre la primera y segunda membranas flexibles. 385
- 3- El sistema de conformidad con la reivindicación 2, caracterizado además porque el fluido retirado entre la primera y segunda membranas flexibles incluye aire o líquido, y el fluido introducido entre la primera y segunda membranas flexibles incluye aire.
- 4- El sistema de conformidad con la reivindicación 1, caracterizado además porque la superficie de control es una hoja de material de polímero resiliente.
- 5- El sistema de conformidad con la reivindicación 1, caracterizado además porque la superficie de control incluye una pluralidad de porciones movibles, al menos una porción movible está dispuesta para ¡nteractuar con la porción de la primera membrana flexible suprayacente a la cámara de bombeo, y al menos otra porción movible está dispuesta para ¡nteractuar con otra porción de la primera membrana flexible para controlar el flujo en un canal del casete de bombeo.
- 66- El sistema de conformidad con la reivindicación 1, caracterizado además porque la superficie de control incluye una pluralidad de puertos para retirar fluido en un espacio entre la primera y segunda membranas flexibles.
- 77,- El sistema de conformidad con la reivindicación 6, caracterizado además porque la pluralidad de puertos también está dispuesta para introducir fluido en el espacio entre la primera y segunda membranas flexibles.
- 8- El sistema de conformidad con la reivindicación 1, 386 caracterizado además porque el ciclador incluye un múltiple con válvulas para controlar el flujo de presión negativa y positiva al al menos un puerto.
- 99, - El sistema de conformidad con la reivindicación 1, caracterizado además porque el múltiple con válvulas es controlable para proporcionar selectivamente presión negativa al al menos un puerto y presión positiva al al menos un puerto.
- 1010, - El sistema de conformidad con la reivindicación 1, caracterizado además porque el al menos un puerto incluye un orificio en la segunda membrana flexible.
- 1111, - El sistema de conformidad con la reivindicación 1, caracterizado además porque la introducción de fluido en el espacio entre la primera y segunda membranas flexibles ayuda a separar el casete de bombeo de la superficie de control del ciclador.
- 1212, - El sistema de conformidad con la reivindicación 1, caracterizado además porque el ciclador incluye un bloque de suministro de presión que respalda la superficie de control e incluye cámaras o depresiones de control en asociación con las regiones de control correspondientes de la superficie de control, cada cámara o depresión de control está dispuesta para mover la región de control correspondiente basándose en una presión de fluido en la región o depresión de control.
- 1313, - Un sistema para acoplar un casete de bombeo de fluido con una unidad de base que proporciona presión positiva y negativa al casete de bombeo que comprende:un casete de bombeo que tiene un cuerpo 387 generalmente plano y una primera membrana flexible sobre un lado del casete suprayacente a la cámara de bombeo sobre el casete;una unidad de base que comprende una fuente de presión positiva, una fuente de presión negativa, un múltiple de distribución de presión, un bloque de suministro de presión y una superficie de control;el múltiple de distribución de presión comprende canales con válvulas entre las fuentes de presión positiva y negativa y el bloque de suministro de presión;el bloque de suministro de presión comprende una depresión en comunicación fluida con válvulas con fuentes de presión positiva y negativa, la depresión está dispuesta para acoplarse con una cámara de bombeo del casete;la superficie de control comprende una segunda membrana flexible y se posiciona sobre el bloque de suministro de presión para estar interpuesto entre la primera membrana flexible del casete y la depresión del bloque de suministro de presión;en donde el múltiple de distribución de presión está configurado para proporcionar un canal con válvulas entre la fuente de presión negativa y la región entre la primera y segunda membranas flexibles opuestas para generar un sello de vacío entre la primera y segunda membranas flexibles para la operación del casete de bombeo, y el múltiple de distribución de presión está configurado para proporcionar un canal con válvulas entre la fuente de presión positiva y una región entre la primera y segunda membranas flexibles opuestas para facilitar el desprendimiento del casete de bombeo de la unidad de base.
- 1414,- Un método para realizar diálisis peritoneal que usa un 388 volumen total pre-determinado de dializado y que comprende una pluralidad de ciclos de terapia, cada ciclo comprende infundir dializado en una cavidad peritoneal, permitir que el dializado se fije en la cavidad peritoneal por un periodo de tiempo y drenar el dializado de la cavidad peritoneal, el método comprende:seleccionar un valor para un volumen máximo de dializado que puede residir en la cavidad peritoneal;seleccionar un valor para un primer volumen de infusión de dializado a infundirse en la cavidad peritoneal;estimar un volumen de fluido de ultrafiltración producido en la cavidad peritoneal durante un ciclo de terapia;medir el volumen de dializado infundido en la cavidad peritoneal durante un ciclo;medir el volumen de dializado drenado de la cavidad peritoneal durante el ciclo;estimar un volumen de dializado residual restante en la cavidad peritoneal;e iniciar un nuevo ciclo de terapia antes de que el total del volumen infundido más el volumen ultrafiltrado estimado de fluido se hayan drenado, siempre y cuando un volumen residual estimado de dializado en la cavidad peritoneal más la cantidad del volumen infundido más el volumen ultrafiltrado estimado en el nuevo ciclo de terapia no excedan el volumen máximo de dializado que puede residir en la cavidad peritoneal.
- 1515,- El método de conformidad con la reivindicación 14, caracterizado además porque comprende adicionalmente seleccionar un tiempo máximo para drenar el dializado de la cavidad peritoneal y agregar uno o más ciclos de terapia adicionales a la pluralidad de ciclos de terapia y reducir el volumen de dializado infundido durante un nuevo ciclo de terapia a un segundo volumen de infusión si el volumen residual estimado restante en 389 la cavidad peritoneal más el primer volumen de infusión más el volumen ultrafiltrado estimado exceden el volumen máximo de dializado que puede residir en la cavidad peritoneal.
- 16- El método de conformidad con la reivindicación 14, caracterizado además porque la infusión y el drenado de dializado se realizan por medio de una bomba de un aparato de diálisis peritoneal, y en donde un controlador del aparato de diálisis peritoneal controla la medición de los volúmenes infundidos y drenados, y determina si el volumen restante estimado más la cantidad del primer volumen infundido más el volumen ultrafiltrado estimado exceden el volumen máximo de dializado que puede residir en la cavidad peritoneal.
- 1717 - El método de conformidad con la reivindicación 15, caracterizado además porque la infusión y drenado de dializado se realizan por medio de una bomba de un aparato de diálisis peritoneal, y en donde un controlador del aparato de diálisis peritoneal controla la medición de los volúmenes infundidos y drenados, determina si el volumen restante estimado más la cantidad del primer volumen infundido más el volumen ultrafiltrado máximo exceden el volumen máximo de dializado que puede residir en la cavidad peritoneal, y determina una cantidad por la cual se puede reducir un segundo volumen infundido del primer volumen infundido si uno o más ciclos de terapia se agregan a la pluralidad de ciclos de terapia, en donde el método comprende adiclonalmente reducir el volumen de dializado infundido durante un nuevo ciclo de terapia al segundo volumen de infusión si el volumen 390 residual estimado restante en la cavidad peritoneal más el primer volumen de infusión más el volumen ultrafiltrado estimado exceden el volumen máximo de dializado que puede residir en la cavidad peritoneal.
- 1818,- Un sistema de diálisis peritoneal para realizar diálisis 5 peritoneal usando un volumen total pre-determinado de dializado y dispuesto para emplear una pluralidad de ciclos de terapia que comprenden una fase de llenado en la que el dializado se suministra desde el sistema de diálisis vía una línea del paciente, una fase de fijación y una fase de drenado en la que el fluido se drena vía una línea de drenado, el sistema comprende:al menos una 10 cámara de bomba controlable para mover fluido;una línea del paciente en comunicación fluida con la al menos una cámara de bomba para recibir dializado desde la al menos una cámara de bomba para suministro;una línea de drenado en comunicación fluida con la al menos una cámara de bomba para suministrar fluido a la al menos una cámara de bomba;una pluralidad de 15 válvulas para controlar selectivamente el flujo en los canales de flujo del sistema de diálisis;y un sistema de control dispuesto para controlar el sistema de diálisis para realizar lo siguiente: controlar la al menos una cámara de bomba y la pluralidad de válvulas para suministrar un primer volumen de infusión de dializado a la línea del paciente como parte de un ciclo de terapia;20 medir un volumen de dializado suministrado a la línea del paciente durante el ciclo de terapia;controlar la al menos una cámara de bomba y la pluralidad de válvulas para recibir fluido de la línea de drenado como parte del ciclo de terapia;medir un volumen de fluido recibido de la línea de drenado durante el 391 ciclo de terapia;estimar un volumen de fluido de ultrafiltración producido durante el ciclo de terapia;estimar un volumen de fluido residual para el ciclo de terapia basándose en el volumen medido de fluido recibido, el fluido de ultrafiltración estimado producido y el volumen medido de dializado suministrado;determinar un valor para un volumen máximo de fluido al final de una fase de fijación;e iniciar un ciclo de terapia siguiente si el volumen residual estimado de fluido para el ciclo más un volumen de dializado a suministrarse para el siguiente ciclo de terapia más un volumen estimado de fluido de ultrafiltración producido para el siguiente ciclo de terapia no exceden el volumen máximo de fluido al final de la fase de fijación.
- 1919, - Un sistema para controlar la temperatura de un conector de línea de solución que tiene un sello perforable a través del cual se puede conectar una espiga hueca, que comprende:un carro sobre el cual se coloca el conector;un detector montado sobre el carro para detectar la temperatura del conector;un elemento de calentamiento o enfriamiento posicionado cerca del conector para afectar la temperatura del conector;y un controlador para recibir datos de temperatura del detector y para controlar al elemento de calentamiento o enfriamiento.
- 2020, - El sistema de conformidad con la reivindicación 19, caracterizado además porque el carro está montado en una puerta de un aparato de diálisis peritoneal, y es movible para portar el conector de la línea de solución a una espiga de un casete de bombeo montado en el aparato de diálisis peritoneal cuando la puerta está en una posición cerrada. 392
- 2121, - Una junta para transferir presión positiva o negativa desde un aparato de diálisis peritoneal a un casete de bombeo, el casete tiene un cuerpo generalmente plano y una primera membrana flexible que cubre una o más cámaras de bomba o de válvula sobre el casete, la junta comprende:una o más regiones de control, cada una comprende una segunda membrana flexible dispuesta para alinearse con una o más cámaras de bombeo o de válvula sobre el casete de bombeo, las cámaras de bombeo o de válvula están cada una unidas por al menos una porción de la primera membrana flexible, cada una de dichas porciones de la primera membrana flexible está dispuesta para hacer contacto directo con una región de control opuesta;una región de perímetro dispuesta para ajustar la junta con seguridad sobre un bloque de suministro de presión del aparato de diálisis peritoneal, el bloque de suministro de presión está configurado para canalizar presión positiva o negativa a la una o más regiones de control;en donde una superficie de cada una de las regiones de control de cara a la primera membrana flexible se hace rugosa o texturizada para formar una capa porosa de la superficie de la región de control cuando se coloca en contacto con la primera membrana flexible.
- 2222, - Un sistema de componente desechable para usarse con un sistema de conexión de línea de fluido de un sistema de diálisis peritoneal, el sistema de componente desechable comprende:un casete de manejo de fluido que comprende: un cuerpo generalmente plano con al menos una cámara de bomba formada como una depresión en un primer lado del cuerpo y una pluralidad de trayectorias de flujo para fluido;una espiga de línea de 393 solución ubicada en un primer extremo del cuerpo, la espiga de línea de solución está en comunicación fluida con la al menos una cámara de bomba vía al menos una trayectoria de flujo;y una tapa de espiga configurada para cubrir de forma removible la espiga de línea de solución, en donde la tapa incluye al menos una brida sobre una superficie exterior de la tapa de espiga para ayudar en el retiro de la tapa de la espiga para conexión de la espiga a la línea de solución, y una lengüeta sobre la superficie exterior de la tapa de espiga configurada para engancharse con la tapa de espiga con un orificio de una tapa de una línea de solución.
- 2323, - El sistema de componente desechable de conformidad con la reivindicación 22, caracterizado además porque el casete de manejo de fluido además comprende al menos dos o más postes dispuestos alrededor de la base de cada espiga para centrar una base de la tapa de espiga sobre la espiga de la línea de solución, en donde una superficie interior de la tapa de espiga y una superficie exterior de la espiga de la línea de solución están en comunicación fluida con una superficie externa del casete de manejo de fluido.
- 2424, - El sistema de componente desechable de conformidad con la reivindicación 23, caracterizado además porque una superficie interior de la base de la tapa de espiga comprende una pluralidad de nervaduras interrumpidas que forman una circunferencia de la tapa de espiga, y en donde la superficie exterior de la espiga de la línea de solución permanece en comunicación fluida con la superficie externa del casete de manejo de fluido.
- 2525, - El sistema de componente desechable de conformidad con 394 la reivindicación 22, caracterizado además porque la tapa de espiga comprende al menos dos o más nervaduras longitudinales sobre la superficie interior cerca de un extremo distal de la tapa de espiga, las nervaduras longitudinales están dispuestas para centrar la tapa de espiga sobre una porción distal de la espiga de la línea de solución.
- 26- El sistema de componente desechable de conformidad con la reivindicación 22, caracterizado además porque la tapa de espiga comprende un extremo distal romo ahusado dispuesto para guiar el enganche de la tapa de espiga con un orificio de la tapa de la línea de solución.
- 2727, - Un módulo de distribución de presión para un aparato de control de flujo de fluido configurado para operar un casete de bombeo a base de membranas, el módulo comprende:un múltiple que comprende un puerto de entrada para presión positiva y un puerto de entrada para presión negativa, y una pluralidad de canales y válvulas dispuestas para conectar selectivamente una fuente de presión positiva o negativa a una pluralidad de canales de salida;un bloque de suministro de presión configurado para acoplarse con un lado del múltiple, en donde una pluralidad de canales de salida del múltiple se conectan fluidamente con puertos opuestos sobre un primer lado del bloque de suministro de presión, los puertos opuestos sobre el primer lado del bloque de suministro de presión están conectados fluidamente con los puertos de salida correspondientes sobre un segundo lado opuesto del bloque de suministro de presión;y una junta de control montada sobre el segundo lado del bloque de suministro de presión y que tiene una pluralidad 395 de regiones de control, cada región de control tiene un primer lado posicionado opuesto a un puerto de salida del bloque de suministro de presión, y cada región de control tiene un segundo lado opuesto configurado para hacer contacto con y accionar una membrana de bombeo o de válvula de un casete de bombeo;en donde cada región de control se puede presurizar positiva o negativamente a través de un puerto de salida correspondiente del bloque de suministro de presión.
- 28- El módulo de conformidad con la reivindicación 27, caracterizado además porque el múltiple incluye una cámara en comunicación fluida con el puerto de entrada para presión negativa y en comunicación fluida con uno o más puertos de salida del bloque de suministro de presión, la cámara está dispuesta en un lado inferior del múltiple para recolectar cualquier fluido recibido del uno o más puertos de salida.
- 2929, - El módulo de conformidad con la reivindicación 28, caracterizado además porque comprende adicionalmente uno o más detectores de líquido dispuestos para detectar la presencia de líquido en la cámara.
- 30- El módulo de conformidad con la reivindicación 28, caracterizado además porque el puerto de entrada para presión negativa y el uno o más puertos de salida están conectados en un extremo superior de la cámara.
- 3131, - El módulo de conformidad con la reivindicación 27, caracterizado además porque el primer lado del bloque de suministro de 396 presión es una cara posterior del bloque de suministro de presión, y el lado del múltiple con el que la cara posterior del bloque de suministro de presión se acopla es una cara frontal del múltiple.
- 3232, - El módulo de conformidad con la reivindicación 31, caracterizado además porque el segundo lado del bloque de suministro de presión es una cara frontal del bloque de suministro de presión.
- 3333, - El módulo de conformidad con la reivindicación 32, caracterizado además porque el múltiple incluye una pluralidad de válvulas para controlar el flujo entre un puerto de entrada para presión positiva o negativa y uno o más canales de salida, cada una de las válvulas es recibida en un puerto de válvula correspondiente formado en una cara lateral del múltiple.
- 3434, - El módulo de conformidad con la reivindicación 33, caracterizado además porque la pluralidad de válvulas incluye en cada válvula un cartucho de válvula recibido en un puerto de válvula correspondiente.
- 3535, - El módulo de conformidad con la reivindicación 27, caracterizado además porque el múltiple incluye una pluralidad de válvulas para controlar el flujo entre un puerto de entrada para presión positiva o negativa y uno o más canales de salida.
- 3636, - El módulo de conformidad con la reivindicación 35, caracterizado además porque el múltiple incluye una pluralidad de puertos de válvula y cada uno recibe una válvula de cartucho.
- 3737 - El módulo de conformidad con la reivindicación 27, 397 caracterizado además porque al menos algunos de los canales de salida están formados por hendiduras en el lado del múltiple al que está acoplado el bloque de suministro de presión.
- 38- Un sistema de calentamiento para un aparato de diálisis peritoneal que comprende:un aparato de bombeo configurado para bombear dializado hacia adentro o hacia afuera de una bolsa del calentador;un calentador eléctrico configurable para operar a un voltaje de línea de AC en un intervalo de aproximadamente 100 a 120 voltios o a un voltaje de línea de AC en un intervalo de aproximadamente 200 a 240 voltios;un controlador configurado para controlar la temperatura del dializado usando el calentador eléctrico;y una fuente universal de energía configurada para convertir voltaje de línea a uno o más voltajes de DC para energizar el aparato de bombeo y el controlador, y para configurar el calentador eléctrico para operar a un voltaje en un intervalo de aproximadamente 100 a 120 voltios o en un intervalo de aproximadamente 200 a 240 voltios, basándose en un flujo de corriente medido a través del calentador eléctrico.
- 3939, - El sistema de calentamiento de conformidad con la reivindicación 38, caracterizado además porque el calentador eléctrico comprende dos elementos de calentamiento, un extremo de cada elemento de calentamiento está conectado a un punto común;en donde la fuente universal de energía comprende uno o más interruptores eléctricos que conectan los elementos de calentamiento a la línea de voltaje en una configuración que se puede cambiar entre una configuración en paralelo o en serie;y en donde la 398 fuente universal de energía comprende un circuito para medir la corriente eléctrica a través del calentador eléctrico, y un controlador de fuente de energía dispuesto para controlar los interruptores eléctricos para configurar los elementos de calentamiento basándose en la corriente medida.
- 4040, - El sistema de calentamiento de conformidad con la reivindicación 39, caracterizado además porque el controlador de fuente de energía está dispuesto para medir la corriente eléctrica a través del calentador eléctrico en una configuración en serie, y para controlar el uno o más interruptores eléctricos para cambiar la configuración de los elementos de calentamiento si la corriente medida es menor que un valor pre-determinado.
- 4141, - Un método para configurar los elementos de calentamiento de un calentador eléctrico para un aparato de diálisis peritoneal, el calentador eléctrico comprende dos elementos de calentamiento, un extremo de cada elemento de calentamiento está conectado a un punto común, el método comprende:configurar los elementos de calentamiento inicialmente en una configuración en serie;conectar el calentador eléctrico a un voltaje de línea;medir el flujo de corriente eléctrica a través del calentador eléctrico;determinar a partir del flujo de corriente medido si el voltaje de línea está en un intervalo de aproximadamente 100-120 voltios, o en un intervalo de aproximadamente 200-240 voltios;proporcionar al usuario del aparato de diálisis peritoneal información acerca del voltaje de línea determinado;y recibir una señal de verificación del usuario antes de configurar finalmente los elementos de calentamiento ya sea en configuración en serie o en 399 configuración en paralelo.
- 42r Un sistema de calentamiento para un aparato de diálisis peritoneal que comprende:una bolsa del calentador que contiene solución de dializado y posicionada sobre una bandeja del calentador;un aparato de bombeo configurado para bombear dializado hacia adentro y hacia afuera de la bolsa del calentador;un elemento de calentamiento eléctrico para calentar la bandeja del calentador;uno o más detectores de temperatura de la bandeja del calentador para detectar la temperatura de la bandeja del calentador;un detector de temperatura de dializado montado en la bandeja del calentador, aislado térmicamente de la bandeja del calentador y configurado para contactar una superficie exterior de la bolsa del calentador;y un controlador programado para realizar un proceso de bucle de control interior que modula la energía eléctrica proporcionada al elemento de calentamiento para lograr una temperatura objetivo de la bandeja del calentador medida por medio de uno o más detectores de temperatura de la bandeja del calentador, y programado para realizar un proceso de bucle de control exterior que determina la temperatura objetivo de la bandeja del calentador basándose en la diferencia entre una temperatura objetivo de dializado pre-determinada y la temperatura de dializado medida por medio del detector de temperatura del dializado.
- 4343, - Un sistema de calentamiento de líquido que comprende:una bolsa del calentador que contiene un líquido y está posicionada sobre la bandeja del calentador;un aparato de bombeo configurado para bombear 400 líquido hacia adentro y hacia afuera de la bolsa del calentador;un elemento de calentamiento eléctrico para calentar la bandeja del calentador;uno o más detectores de temperatura de la bandeja de calentamiento para detectar la temperatura de la bandeja del calentador;un detector de temperatura de 5 líquidos montado en la bandeja del calentador, aislado térmicamente de la bandeja del calentador y configurado para contactar una superficie exterior de la bolsa del calentador;y un controlador programado para realizar un proceso de bucle de control interior que modula la energía eléctrica proporcionada al elemento del calentador para lograr una temperatura objetivo de la bandeja 10 del calentador medida por medio de uno o más detectores de temperatura de la bandeja del calentador, y programado para realizar un proceso de bucle de control exterior que determine la temperatura objetivo de la bandeja del calentador basándose en la diferencia entre la temperatura objetivo predeterminada del líquido y la temperatura de equilibrio, en donde la 15 temperatura de equilibrio es un promedio ponderado de la temperatura del líquido y la temperatura de la bandeja del calentador, la temperatura del líquido se pondera por medio de una capacitancia térmica, masa o volumen de líquido presente en la bolsa del calentador, y la temperatura de la bandeja del calentador se pondera por medio de una capacitancia térmica, masa o 20 volumen de la bandeja del calentador.
- 44- Un sistema de calentamiento de líquido que comprende:una bolsa del calentador que contiene un líquido y está posicionada sobre la bandeja del calentador;un aparato de bombeo configurado para bombear 401 líquido hacia adentro y hacia afuera de la bolsa del calentador;un elemento de calentamiento eléctrico para calentar la bandeja del calentador;uno o más detectores de temperatura de la bandeja del calentador para detectar la temperatura de la bandeja del calentador;un detector de temperatura de líquidos montado en la bandeja del calentador, aislado térmicamente de la bandeja del calentador y configurado para contactar una superficie exterior de la bolsa del calentador;y un controlador programado para realizar un proceso de bucle de control interior que modula la energía eléctrica proporcionada al elemento del calentador para lograr una temperatura objetivo de la bandeja del calentador medida por medio de uno o más detectores de temperatura de la bandeja del calentador, y programado para realizar un proceso de bucle de control exterior que determine la temperatura objetivo de la bandeja del calentador basándose en la diferencia entre la temperatura objetivo predeterminada del líquido y la temperatura de equilibrio, en donde la temperatura de equilibrio es un promedio ponderado de la temperatura del líquido y la temperatura objetivo de la bandeja del calentador, la temperatura del líquido se pondera por medio de una capacitancia térmica, masa o volumen de líquido presente en la bolsa del calentador, y la temperatura objetivo de la bandeja del calentador se pondera por medio de la capacitancia térmica, masa o volumen de la bandeja del calentador.
- 45- El sistema de calentamiento de líquido de conformidad con la reivindicación 44, caracterizado además porque el proceso de bucle de control interior incluye un elemento de integrador que genera un valor integral 402 con lógica anti-serpenteo para limitar un valor integral de la diferencia entre la temperatura objetivo de la bandeja del calentador y la temperatura medida de la bandeja del calentador.
- 4646, - El sistema de calentamiento de líquido de conformidad con la reivindicación 44, caracterizado además porque el proceso de bucle de control interior incluye un comando de energía máxima del calentador, el proceso de bucle de control exterior incluye una temperatura objetivo máxima de la bandeja del calentador, y el proceso de bucle de control exterior incluye un elemento de integrador que se aplica si:la velocidad de cambio de la temperatura del líquido es menor que un valor pre-determinado;la temperatura del líquido está dentro de un intervalo pre-determinado de la temperatura objetivo del líquido;la cantidad de líquido en la bolsa del calentador es mayor que un valor pre-determinado;o ni un valor de salida del proceso de bucle de control interior, ni un valor de salida del proceso de bucle de control exterior están en valores máximos pre-determinados.
- 4747, - El sistema de calentamiento de líquido de conformidad con la reivindicación 44, caracterizado además porque el controlador está configurado para establecer la energía eléctrica en cero si la temperatura de la bandeja excede un valor pre-determinado.
- 4848, - Un sistema de control para un aparato de suministro de fluido médico que comprende:un aparato de bombeo configurado para bombear fluido a un paciente desde uno o más contenedores de fuente de fluido, o de un paciente a un receptáculo, el aparato comprende una o más 403 bombas, una o más válvulas y conexiones fluidas entre las bombas, válvulas y los contenedores de fuente o receptáculo de fluido;uno o más detectores de presión para detectar las presiones de bombeo de la una o más bombas;un primer procesador configurado para controlar la secuencia y sincronización de las operaciones de válvula y de bomba para implementar un bombeo de fluido desde uno o más contenedores de fuente al paciente o desde el paciente al receptáculo, y configurado para monitorear uno o más volúmenes del fluido que se está bombeando;y un segundo procesador configurado para implementar comandos del primer procesador y para proporcionar datos al primer procesador, en donde el segundo procesador está configurado para: recolectar y almacenar datos recibidos de los detectores de presión a una velocidad fija pre-determinada;proporcionar los datos almacenados al primer procesador a la orden del primer procesador;controlar la presión de bombeo de la una o más bombas sobre un horario fijo pre-determinado;y abrir o cerrar las válvulas a la orden del primer procesador.
- 4949,- Un sistema de administración de energía para un dispositivo médico mientras opera con energía de batería que comprende:un dispositivo médico que tiene una pluralidad de funciones, cada función está asociada con uno de un número pre-determinado de niveles de consumo de energía;un circuito electrónico configurado para medir una cantidad de carga restante en una batería que energiza un dispositivo médico, y asociar la cantidad de carga con uno de los niveles pre-determinados de consumo de energía;y un controlador configurado para permitir que el dispositivo médico 404 realice una o más funciones de la pluralidad de funciones, siempre y cuando la una o más funciones y la cantidad medida de carga estén asociadas con el mismo nivel de consumo de energía. 405
Independent claims49
1,129 paragraphs in 10 sections, as filed
(54) Title: MEDICAL TREATMENT SYSTEM AND METHODS USING A PLURALITY OF FLUID LINES.
(54) Title: MEDICAL TREATMENT SYSTEM AND METHODS USING A PLURALITY OF FLUID LINES.
(57) Summary
A medical treatment system, such as a peritoneal dialysis system, may include monitoring and other features to improve patient comfort and ease of use; for example, a peritoneal dialysis system may include a control system that can adjust the volume of fluid infused into the peritoneal cavity to prevent the volume of intraperitoneal fluid from exceeding a predetermined amount; the control system can adjust by adding one or more therapy cycles, allowing to reduce the filling volumes during each cycle; the control system can continue to allow fluid to drain from the peritoneal cavity as completely as possible before starting the next cycle of therapy; the control system can also adjust the fluid residence time within the peritoneal cavity during therapy cycles to complete a therapy within a scheduled period; The cycler can also be configured to have a heater control system that monitors both the temperature of a heating tray and the temperature of a dialysis fluid bag to quickly bring the temperature of the dialysis fluid to a specific temperature, with minimal excess temperature.
(57) Abstract
A medical treatment system, such as peritoneal dialysis system, may include control and other features to enhance patient comfort and ease of use. For example, a peritoneal dialysis system may include a control system that can adjust the volume of fluid infused into the peritoneal cavity to prevent the intraperitoneal fluid volume from exceeding a preÁ-> determined amount. The control system can adjust by adding one or more therapy cycles, allowing for fIII volumes during each cycle to be reduced. The control system may continue to allow the fluid to drain from the peritoneal cavity as completely as possible before starting the next therapy cycle. The control system may also adjust the dwell time of fluid within the peritoneal cavity during therapy cycles in order to complete a therapy within a scheduled time period. The cycler may also be configured to have a heater control system that monitors both the temperature of a heating tray and the temperature of a bag of dialysis fluid ¡n orderto brlng the temperature of the dlalysls fluid rapldly to a speclfled temperature, wlth minimal temperature overshoot .
MEDICAL TREATMENT SYSTEM AND METHODS USED
A PLURALITY OF FLUID LINES
This application is a continuation in part of US Application No. 13 / 178,191 filed on July 7, 2011, which claims the benefit of US Provisional Application No. 61 / 362,259, filed on July 7, 2010.
This application is a continuation in part of US Application No. 12 / 864,357, filed on July 23, 2010, which is a national stage of PCT application PCT / US2009 / 000440, filed on January 23, 2009, which claims the benefit of US Provisional Application No. 61 / 011,967, filed on January 23, 2008, and US Provisional Application No. 61 / 058,469, filed on June 3, 2008.
This application is a continuation in part of US Application No. 12 / 864,378, filed on July 23, 2010, which is a national stage of PCT application PCT / US2009 / 000436, filed on January 23, 2009, which claims the benefit of US Provisional Application No. 61 / 011,967, filed on January 23, 2008, and US Provisional Application No. 61 / 058,469, filed on June 3, 2008.
This application is a continuation in part of US Application No. 12 / 864,391, filed on July 23, 2010, which is a national stage of PCT application PCT / US2009 / 000439, filed on January 23, 2009, which claims the benefit of US Provisional Application No.
61 / 011,967, filed on January 23, 2008, and US Provisional Application No. 61 / 058,469, filed on June 3, 2008.
This application is a continuation in part of US Application No. 12 / 864,287, filed on July 23, 2010, which is a national stage of PCT application PCT / US2009 / 000437, filed on January 23, 2009, which claims the benefit of US Provisional Application No. 61 / 011,967, filed on January 23, 2008, and US Provisional Application No. 61 / 058,469, filed on June 3, 2008.
This application is a continuation in part of US Application No. 12 / 864,293, filed on July 23, 2010, which is a national stage of PCT application PCT / US2009 / 000433, filed on January 23, 2009, which claims the benefit of US Provisional Application No. 61 / 011,967, filed on January 23, 2008, and US Provisional Application No. 61 / 058,469, filed on June 3, 2008.
This application is a continuation in part of US Application No. 12 / 864,322, filed on July 23, 2010, which is a national stage of PCT application PCT / US2009 / 000441, filed on January 23, 2009, which claims the benefit of US Provisional Application No. 61 / 011,967, filed on January 23, 2008, and US Provisional Application No. 61 / 058,469, filed on June 3, 2008.
This application claims the benefit of Provisional Application No. 61 / 555,926, filed on November 4, 2011.
The foregoing requests are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
Peritoneal Dialysis (PD) involves the periodic infusion of sterile aqueous solution (called dialysis or peritoneal dialysis solution) into a patient's peritoneal cavity. Diffusion and osmosis exchanges take place between the solution and the bloodstream through the natural body membranes. These exchanges transfer waste products to the dialysate that the kidneys normally excrete. Waste products typically consist of solutes such as sodium and chlorine ions, and other compounds normally excreted through the kidneys such as urea, creatinine, and water. The diffusion of water through the peritoneal membrane during dialysis is called ultrafiltration.
Conventional peritoneal dialysis solutions include dextrose in sufficient concentrations to generate the osmotic pressure necessary to remove water from the patient through ultrafiltration.
Continuous Ambulatory Peritoneal Dialysis (CAPD) is a popular form of PD. A patient performs CAPD manually approximately four times a day. During a CAPD drain / fill procedure, the patient initially drains spent peritoneal dialysis solution from their peritoneal cavity, and then infuses fresh peritoneal dialysis solution into their peritoneal cavity. This procedure of
<img file="MX2014005451A_D0001.tif" />
Draining and filling usually requires approximately 1 hour.
Automated Peritoneal Dialysis (APD) is another popular form of PD. The APD uses a machine, called a cycler, to automatically infuse, reside, and drain peritoneal dialysis solution to and from the patient's peritoneal cavity. APD is particularly attractive to a PD patient because it can be performed at night while the patient is asleep. This frees the patient from the day-to-day requirements of CAPD during their waking and working hours.
The APD sequence typically lasts for several hours. It often begins with an initial drainage phase to empty the spent dialysate peritoneal cavity. The APD sequence then proceeds through a succession of fill, reside, and drain phases that follows one after the other. Each fill / residence / drain sequence is called a cycle.
During the filling phase, the cycler transfers a predetermined volume of warm, fresh dialysate into the patient's peritoneal cavity. The dialysate remains (or "resides") within the peritoneal cavity for a period of time. This is called the residency phase. During the drainage phase, the cycler removes the spent dialysate from the peritoneal cavity.
The number of fill / residence / drain cycles required during a given APD session depends on the total volume of dialysate prescribed for the patient's APD regimen and is entered as part of the treatment prescription or calculated using the cycler .
APD can and is practiced in different ways.
Continuous Cycling Peritoneal Dialysis (CCPD) is a commonly used APD modality. During each CCPD fill / residence / drain phase, the cycler infuses a prescribed volume of dialysate. After a prescribed residence period, the cycler completely drains this volume of fluid from the patient, leaving the peritoneal cavity empty, or "dry." Typically, CCPD employs 4-8 fill / residence / drain cycles to achieve a prescribed volume of therapy.
After the last prescribed fill / residence / drain cycle in CCPD, the cycler infuses a final fill volume. The final fill volume resides in the patient for an extended period of time. It is drained either at the start of the next CCPD session at night or during a half-day exchange. The final fill volume may contain a different concentration of dextrose from the fill volume of the successive CCPD fill / residence / drain cycles provided by the cycler.
Intermittent Peritoneal Dialysis (IPD) is another modality of APD. IPD is typically used in acute situations, when a patient suddenly enters dialysis therapy. IPD can also be used when the patient requires PD, but cannot assume the responsibilities of CAPD or do otherwise in the home.
Like CCPD, IPD involves a series of fill / residence / drain cycles. Unlike CCPD, IPD does not include a final fill phase. In IPD, the patient's peritoneal cavity is free of dialysate (or "dry") between APD therapy sessions.
Peritoneal Dialysis of Physiological Variation (TPD) is another modality of APD. Like the CCPD, the TPD includes a series of fill / residence / drain cycles. Unlike CCPD, TPD does not completely drain the dialysate from the peritoneal cavity during each drainage phase. Rather, the TPD establishes a base volume during the first fill phase and drains only a portion of this volume during the first drain phase. Subsequent fill / residence / drain cycles infuse and then drain a replacement volume over the top of the base volume. The last drainage phase removes all the dialysate from the peritoneal cavity.
There is a variation of TPD that includes cycles during which the patient is completely drained and infused with a new full-base dialysis volume.
The TPD may include a final fill cycle, such as the CCPD. Alternatively, the TPD can avoid the final fill cycle, like the IPD.
APD offers flexibility and quality of life improvements to a person requiring dialysis. APD can free the patient from the fatigue and inconvenience that the day-to-day practice of CAPD represents for some individuals. APD can return the patient to their waking and work hours free of the need to conduct a dialysis exchange.
Still, the complexity and size of the associated disposable and prior machines for various APD modalities have impeded the patient's wide acceptance of APD as an alternative to manual peritoneal dialysis methods.
BRIEF DESCRIPTION OF THE INVENTION
Aspects of the invention relate to various components, systems, and methods for use in medical applications, including medical infusion operations such as peritoneal dialysis. In some cases, aspects of the invention are limited to applications in peritoneal dialysis, while others to more general dialysis applications (eg, hemodialysis) or infusion applications, while others to more general methods or processes. Thus, aspects of the invention are not necessarily limited to APD systems and methods, although many of the illustrative embodiments described relate to APD.
In one aspect of the invention, a tube condition detector can be included with a dialysis system to detect the presence or absence of a segment of the tube, such as a portion of a patient line to be connected to a patient port to supply the dialysate to the peritoneal cavity. The tube condition detector may include a first light emitter having a first optical axis directed towards a space in which a segment of the tube is to be positioned, and a second light emitter adjacent to the first light emitter and having a second optical axis directed into space. An optical detector can be positioned on a side of the space opposite the first and second light emitters and positioned to receive the light emitted by the first and second light emitters to determine the presence or absence of a segment of the tube in space.
In one embodiment, the first optical axis may be approximately co-linear with an optical axis of the optical detector detector, and may pass approximately through the center of a tube segment when the tube segment is placed in space. In contrast, the second optical axis may be approximately parallel to the first optical axis, and thus, the second optical axis may deviate from the center of the tube segment and optical axis of the detector.
The optical detector may be arranged to detect a range of light levels when a tube segment is in space, for example, a light level that is higher and / or lower than a detected light level when the tube segment is absent from space. However, the optical detector can detect a lower light level from the second light emitter when a segment of the tube is in space than is detected when the segment of the tube is absent from space. For example, with a segment of the tube in space, a detected light level for both the first and second light emitters may be within approximately 15-20% of a calibration light level for the first and second emitters. light, where the calibration light level is a detected level when a segment of the tube is known to be absent from space. However, with a segment of the tube that is not in space, a detected light level for the second light emitter may be less than about 15-20% of the calibration light level for the second light emitter. This detection of the lower light level can be used to determine that a segment of the tube is in space.
In another embodiment, the tube condition detector can be arranged to detect if liquid is present in the tube segment, for example, if the patient line is properly started for use. For example, the detector may include a third light emitter having a third optical axis that is disposed at an oblique angle to the optical axis of the detector. The oblique angle can be between 90 and 180 degrees, for example, about 110-120 degrees. The optical detector and third light emitter can be positioned such that with one segment of the tube in space and the segment of the tube without liquid, a light level detected by the optical detector may be above approximately 150% of a level of Calibration light detected without the tube segment in space. Furthermore, with a segment of the tube in space and with liquid, the optical detector can detect a light level from the third light emitter that is less than about 125% of the calibration light level. Thus, the optical detector and third light emitter can be arranged such that with a tube segment in space and the tube segment without liquid, a light level detected by the optical detector may be above a threshold level, and With a segment of the tube in space and the segment of the tube with liquid, the light level detected by the optical detector is less than the threshold level. This
<img file="MX2014005451A_D0002.tif" />
The arrangement can allow the detector to determine if the liquid is contained in the patient line, for example, if the patient line is started properly. In one embodiment, the third light emitter and the optical detector can be positioned such that the optical detector receives light from the third light emitter both when a segment of the tube in space is filled with liquid and when a segment of the tube in space it is empty of liquid. Thus, the presence or absence of liquid in the tube segment can be determined based on a detected intensity of light rather than the presence or absence of light. This can help the system avoid detection of the false condition that can result if the detector uses the absence of detected light to indicate a condition, such as the presence of liquid in the tube segment. That is, since the optical detector detects light from the third light emitter regardless of the presence of liquid, the optical detector may be able to determine if the third light emitter operates properly (or not at all). The space in which the tube segment is held can be arranged to receive and maintain the tube segment, which can have a cylindrical outer surface, without substantially deforming the tube segment. In this way, the detector can operate without deforming the tube segment, thus avoiding potential problems such as pinching, reduced flow in the tube segment, etc.
In another aspect of the invention, a tube condition detector for detecting whether the liquid is contained in a segment of the tube may include a light emitter in the filled state with an optical axis that is arranged to pass through a space in the that a segment of the tube should be positioned. The space may be arranged to receive a tube segment having a cylindrical outer surface and to hold the tube segment without substantially deforming the tube segment. In this way, the detector can be used with common tubes frequently used in dialysis systems and without requiring special purpose accessories or other components. An optical detector can be positioned on a side of the space opposite the light emitter in the full state and arranged to receive the light emitted by the light emitter in the full state to determine the presence or absence of liquid in the tube segment. In one embodiment, the optical detector may have an optical axis of the detector that is positioned at an angle oblique to the optical axis of the light emitter in the full state, and may be arranged to detect whether or not liquid is present in the tube segment. The oblique angle can be between 90 and 180 degrees, for example, about 110-120 degrees, and the optical detector can be positioned to receive light from the light emitter in the full state whether or not liquid is present in the tube segment.
The optical detector and the light emitter in the full state can be arranged such that with a segment of the tube in space and the segment of the tube without liquid, a light level detected by the optical detector may be above a threshold level and that with a segment of the tube in space and the segment of the tube with liquid, a light level detected by the optical detector is less than the threshold level. Thus, if the optical detector detects a light level below a threshold, for example, below approximately 125-150% of a detected light level without any segment of the tube in space, a determination of that the tube segment is filled with liquid. The light emitter in the full state (as with other light emitters) may be a light emitting diode or other electromagnetic radiation emitting component, such as a device that emits infrared, UV, and visible light, or other light in the visible spectrum, and / or invisible.
In one embodiment, the tube condition detector may include a first light emitter that has a first optical axis directed toward space, and a second light emitter that has a second optical axis directed toward space. The second light emitter can be adjacent to the first light emitter, and the second optical axis can be parallel to the first optical axis. The optical detector can be positioned on a side of the space opposite the first and second light emitters and positioned to receive the light emitted by the first and second light emitters to determine the presence or absence of a segment of the tube in space. For example, the first and second light emitters can be arranged relative to each other and the optical detector as described above, for example, the first optical axis can pass through a center of a segment of the tube in space, the second optical axis can deviate from the center of the tube segment, etc.
In another aspect of the invention, a peritoneal dialysis system may include at least one pump positioned to pump dialysate to supply a patient's peritoneal cavity, and a patient line fluidly coupled to at least one pump in a manner that the dialysate supplied from the pump is directed to the patient line. The patient line may have a distal end positioned for connection to a patient, eg, for connection to a patient port to deliver dialysate to a patient's peritoneal cavity. A patient line status detector can be arranged to associate with the patient line and to detect both the presence of the patient line and the initiation condition of the patient line. For example, the patient line status detector can be arranged to receive the distal end of the patient line to detect the presence of the distal end and whether the distal end of the patient line is filled with fluid. This arrangement may be useful to allow the system and a patient to confirm that the patient line is sufficiently full of dialysate before connecting the patient line to the patient access connection.
The patient line status detector may include a cavity to receive the distal end of the patient line, one or more light emitters related to the positioned cavity to direct light into the cavity, and one or more light detectors positioned to detect light emitted by one or more light emitters. In one embodiment, a single light detector can be used to determine both the presence and absence of the patient line, as well as whether liquid is present in the patient line. The patient line status detector can be arranged in any of the ways in which the tube status detectors described above can be placed. For example, the first and second light emitters may be arranged adjacent to each other and on one side of a cavity to receive the patient line that is opposite to an optical detector. A third light emitter can be positioned to have its optical axis positioned obliquely to an axis of the detector of the optical detector, and thus allow detection of liquid in the patient line. Other features of the tube status detectors described above can be incorporated into the patient line status detector, including the detection and use of relative light levels to indicate the presence of the patient line and / or liquid in the patient line, and so on.
In another aspect of the invention, a method of detecting the presence of a segment of the tube includes emitting a first light along a first optical axis into a space where a segment of the tube is to be optionally placed, and emitting a second light along a second optical axis into space, where the first and second lights are emitted from a first side of space. At least the portions of the first and second lights can be detected on a second side of the space opposite the first side, and a presence or absence of a segment of the tube in the space can be determined based on the detected portions of the first and second lights. The second optical axis can be approximately parallel to the first optical axis, and the first optical axis can pass through the center of the tube segment. In one embodiment, a first level calibration of the first light can be detected without the tube segment in space, and a first light level can be detected from the first light when a segment of the tube is in space. The first light level can be higher or lower than the first level of calibration. However, a second level of calibration of the second light can be detected without the tube segment in space, and a second level of light can be detected from the second light when a segment of the tube is in space, where the second level of light is lower than the second level of calibration. Thus, detection of a second light level that is less than the second calibration level can indicate the presence of a segment of the tube in space. In one embodiment, a second detected light level for the second light may be less than about 1520% of the second calibration level with a segment of the tube in space.
In another aspect of the invention, a method of detecting the presence of liquid in a segment of the tube may include emitting light along an optical axis into a space where a segment of the tube is placed, where the segment of the tube has a cylindrical outer surface, and detect light along an optical axis of the detector that extends into space, where the optical axis of the detector is placed at an oblique angle (for example, about 110-120 degrees) relative to the optical axis. The presence or absence of liquid in the tube segment in space can be determined based on a detected light level that is detected along the optical axis of the detector. For example, a determination can be made as to whether fluid is not present in the tube segment if a detected light level along the optical axis of the detector is above a threshold level, and a determination can be made as to whether Fluid is present in the tube segment if a detected light level along the optical axis of the detector is below a threshold level. The threshold level can be approximately equal to approximately 125-150% of a detected light level along the optical axis of the detector without any segment of the tube in space.
In one aspect of the invention, a disposable fluid handling cassette, such as that usable with an APD cycler device or other infusion apparatus, includes a generally flat body having at least one pump chamber formed as a depression in a first body side and a plurality of fluid flow paths including a channel. A patient line port can be arranged for connection to a patient line and be in fluid communication with at least one pump chamber via at least one flow path, and a membrane can be attached to the first side of the body. on at least one pump chamber. In one embodiment, the membrane may have a non-tensioned shaped pump chamber portion that generally conforms to the depression of the pump chamber in the body and is arranged to be movable for fluid movement in usable chamber space. pump. If the cassette body includes two or more pump chamber depressions, the membrane may also include two or more pre-configured pump portions. In other embodiments, the membrane need not be included with the cassette, for example, where a cycler control surface interacts with the cassette to control pumping and / or valve functions.
In another embodiment, the pump chamber may include one or more spacer elements that extend from an interior wall of the depression, for example, to help prevent the membrane from contacting the interior wall, thus preventing blockage of an inlet / outlet from the pump chamber, helping to remove or trap air in the pump chamber, and / or prevent the membrane from sticking to the interior wall. The spacer elements may be arranged to minimize deformation of the membrane at edges of the spacer elements when the membrane is forced against the spacer elements.
In another embodiment, a patient line port and a drain line port may be located at a first end of the body and be in fluid communication with at least one pump chamber via at least one flow path. A plurality of solution line pins, on the other hand, may be located at a second end of the body opposite the first end, with each of the solution line pins being in fluid communication with at least one pump chamber. using at least one flow path. This arrangement can enable automated connection of solution lines to the cassette, and / or separate occlusion from the patient and / or drain lines relative to the solution lines. In one embodiment, a heater bag line port can also be located at the first end of the body and be in fluid communication with at least one pump chamber via at least one flow path. The flexible patient, drain and heater bag lines can be respectively connected to the patient line port, drain line port and heater bag line port.
In another embodiment, the body may include a vacuum vent rinse depression formed adjacent to at least one pump chamber. This depression can aid in the removal of fluid (gas and / or liquid) between the membrane and a corresponding control surface of the cycler, for example, by means of a vacuum port on the control surface. That is, the depression can help ensure that the membrane is not forced against the vacuum port, leaving the port open to bring fluid into a collection chamber as needed.
In one embodiment, one or more ports, such as a drain line port and a heater bag line port, and / or one or more solution line pins can communicate with a common base flow path channel of the cassette. As necessary, a plurality of valves can each be arranged to control flow in a respective flow path between at least one pump chamber and the patient line port, the drain line port, and the plurality of spigots. line solution. In one embodiment, membrane portions can be positioned on respective valves and moveable to open and close the respective valve. Similarly, flow through the openings into the pump chamber (s) can be controlled by corresponding valves that are opened and closed by movement of one or more portions of the membrane.
In some embodiments, the membrane can close at least some of the body's flow paths. That is, the body may be formed with open flow channels that are closed on at least one side by the membrane. In one embodiment, the body may include flow paths formed on opposite flat sides, and at least some of the flow paths on a first side may communicate with flow paths on the second side.
In one embodiment, one or more dowels in the cassette (eg, to receive dialysate solution) may be covered by a dowel cap that seals the closed dowel and is removable.
In another aspect of the invention, a disposable fluid handling cassette, for use with a reusable automated peritoneal dialysis cycler device, includes a generally flat body having at least one pump chamber formed as a depression in a first body side and a plurality of fluid flow paths including a channel, a patient line arranged for connection to a patient line, the port of the patient line is in fluid communication with the at least one pump chamber by means of at least one flow path, and a flexible membrane attached to the first side of the body over the at least one pump chamber. A pump chamber portion of the membrane over at least one pump chamber may have a non-tensioned shape 5 which generally conforms to the usable area of the pump chamber depression in the body and may be arranged to be movable for fluid movement in the pump chamber. In one embodiment, the cassette is configured for operational coupling with a reusable automated peritoneal dialysis cycler device.
The cassette may include a drain line port arranged for connection to a drain line, the drain line port being in fluid communication with at least one pump chamber via at least one flow path, and / or a plurality of solution line pins that are in fluid communication with at least one pump chamber via at least one flow path. The pump chamber portion of the membrane may generally be dome-shaped, and may include two pump chamber portions having a shape that generally conforms to the usable area of a corresponding pump chamber depression. In one embodiment, a volume of the pump chamber portion may be between 85-110% of the usable volume of the pump chamber depression. In another embodiment, the pump chamber portion may be arranged to be 85-110% of the usable area depth of the pump chamber depression. In another modality, the
<img file="MX2014005451A_D0003.tif" />
Pump chamber portion may be arranged to have a size that is between 85-100% of the circumference of the usable area of the pump chamber depression. The usable area of the pump chamber may be defined at least in part by one or more spacer elements extending from an interior wall of the depression. In one embodiment, a plurality of spacer elements can be of graduated lengths or variable height defining a region generally dome-shaped or otherwise. The spacer elements may be arranged in a concentric elliptical pattern or other shape when viewed in plan. One or more breaks in the pattern can be provided, for example, to allow communication between gaps. In one embodiment, the spacer elements may be arranged to minimize deformation of the membrane at edges of the spacer elements when the membrane is forced against the spacer elements. In another embodiment, one or more separators may be configured to inhibit the membrane from covering the fluid inlet and / or outlet of the pump chamber.
In another aspect of the invention, a fluid handling cassette for use with a fluid handling system of a medical infusion device includes a generally flat body having at least one pump chamber formed as a depression on a first side. of the body and a plurality of fluid flow paths including a channel, at least one pump chamber includes one or more spacer elements extending from the inner wall of the depression, a patient line port arranged for connection to a line patient line, the patient line port being in fluid communication with at least one pump chamber via at least one flow path, a drain line port arranged for connection to a drain line, the drain line port being in fluid communication with at least one pump chamber via at least one flow path, and a plurality of solution line taps being in fluid communication with at least one pump chamber via at least one flow path.
In one aspect of the invention, a disposable component system for use with a fluid line connection system of a peritoneal dialysis system includes a fluid handling cassette having a generally flat body with at least one pump chamber formed as a depression on a first side of the body and a plurality of flow paths for fluid, a solution line pin located at a first end of the body, the solution line spike being in fluid communication with at least one pump chamber via at least one flow path, and a spike cap configured to removably cover the solution line spike, wherein the cap includes by at least one elevated feature (eg, asymmetric or symmetrical flange) to help remove the cap for connection to a solution line prior to the start of peritoneal dialysis therapy.
In one embodiment, the cassette includes a skirt arranged around the spike to receive one end of the spike cap, and there may be a depression between the skirt and spike that are arranged to assist in the formation of a seal between the spigot cap. tenon and skirt.
In another embodiment, a solution line cap may be removably connected to a solution line, and the solution line cap may include a depression feature (such as a symmetrical or asymmetric groove). At least a portion of the solution line cap can include a flexible material, such as silicone rubber. The depression feature can aid in the removal of a spigot cap from the cassette.
In another embodiment, the spigot cap includes a second raised feature that can function as a stop for the solution line cap.
In another embodiment, a major axis of one or more pins is in substantially the same plane as the generally flat body of the fluid handling cassette.
In another aspect of the invention, a fluid handling cassette for use in a peritoneal dialysis system includes a generally flat body with at least one pump chamber formed as a depression on a first side of the body and a plurality of trajectories of fluid flow, and a spike located at a first end of the body for engagement with a line of dialysate solution. The stem may be in fluid communication with at least one pump chamber via at least one flow path including a distal tip and a lumen arranged such that the distal tip of the stem is located substantially near the longitudinal axis of the spike. In one embodiment, the lumen may be located substantially outside the longitudinal axis.
In another aspect of the invention, a disposable component system for use with a fluid line connection system of a peritoneal dialysis system includes a spigot cap configured to removably cover a spike of a fluid handling cassette. The cap may include at least one feature to help remove the cap for connection to a solution line prior to the start of peritoneal dialysis therapy. The feature can be a raised feature, or a depression feature, and can be configured for latching with a solution line cap.
In another aspect of the invention, a disposable component system for use with a fluid line connection system of a peritoneal dialysis system includes a solution line cap for removable attachment to a solution line, wherein the Solution line includes at least one feature to aid in the removal of a spike cap to enable the connection between a solution line and a spike prior to beginning peritoneal dialysis therapy. The feature may be a raised feature, or a depression feature, and may be configured for engagement with a spigot cap. Clues may be associated with a solution line, for example, such that a solution associated with the line can be identified and affect at least one function of the peritoneal dialysis system.
In another aspect of the invention, a medical infusion fluid handling system such as an APD system may be arranged to unclog and connect one or more lines (such as solution lines) with one or more spikes or other connection ports. in a flow management cassette. This feature can provide advantages, such as a reduced probability of contamination, since human interaction is not required to uncover and connect the lines and pins. For example, an APD system may include a cart arranged to receive a plurality of solution lines, each of which has a connector end and a cap. The carriage may be arranged to move along a first direction in order to move the connecting ends of the solution lines along the first direction, and a cap separator may be arranged to engage with caps on the solution lines in the car. The lid separator may be arranged to move in a second direction transverse to the first direction as well as to move with the carriage along the first direction. For example, the carriage can be moved to a cassette on an APD cycler in a first direction to hook the caps on the solution lines with the spigot caps on the cassette. The lid separator can engage the lids (eg, by moving in a direction transverse to the carriage movement) and then move with the carriage as the carriage moves away from the cassette to remove the caps from the pins. The carriage can then pull the connector ends of the solution lines from the caps into the cap separator, which can be retracted to allow the carriage to engage the now exposed solution line connector ends with the exposed pins on the cassette.
In one embodiment, the cart may include a plurality of slots that each receive a corresponding solution line. By placing the solution lines in corresponding slots, each of the lines can be more easily identified individually, for example, by reading a barcode or other identifier on the line, and controlling the system accordingly. The cart can be mounted to a door of a cycler housing, and a cart driver can move the cart along the first direction. In one embodiment, the carriage driver can engage the carriage when the door is moved to a closed position and disengage from the carriage when the door is moved to an open position.
In one embodiment, the cap separator may include a plurality of fork-shaped elements arranged to engage with a corresponding cap on a solution line carried by the carriage. The fork-shaped elements can support the caps when they are removed from the solution line and each of the solution line caps can itself support a spigot cap. In another embodiment, the cap separator can include a plurality of swing arms each associated with a fork-shaped element. Each of the swing arms can be arranged to move to engage a pin cap, for example, to help remove the pin cap from the corresponding pin. Each of the oscillating arms can be arranged to engage with a corresponding spigot cap only when the associated hairpin element engages with a cap in a solution line. Therefore, the cap separator may not engage or remove spigot caps from the cassette in places where there is no corresponding solution line to connect to the spigot.
In another aspect of the invention, a method of connecting fluid lines in a medical infusion fluid handling system, such as an APD cycler, may involve locating solution lines and spigots of a cassette in an enclosed space away from the Human contact. Solution lines and / or dowels may have caps removed and lines connected to dowels while in the enclosed space, thus providing the connection while minimizing potential contamination at the connection, for example, by pathogen-bearing fingers or other potentially harmful substances. For example, a method in accordance with this aspect of the invention includes providing a plurality of solution lines each having a connector end and a cap, providing a fluid handling cassette having a plurality of pins each covered by a herringbone cap, enclosing the connector ends of the plurality of solution lines with lids covering the connector ends and the plurality of lugs with lug caps covering the lugs in a space that prevents human contact from the lids or lug covers, removing the connector end caps of a plurality of solution lines without removing the connector caps or ends from the gap, removing the spigot caps from the spigots without removing the spigot caps or spigots from the gap, engaging the caps with respective ones of the spigot caps, and fluidly connecting the plurality of connector ends to corresponding spigots while maintaining the connector ends and spikes in space and protected from human contact.
In one embodiment, the solution line caps and spigot caps can be engaged with each other before being removed from the lines or spikes, and can then be removed from both the lines and spikes while they are engaged with one another. This technique can simplify the uncapping / capping process as well as allow easier lids storage.
In another embodiment, the solution lines may be disconnected from the pins, and the connector ends of the lines and pins may be capped, for example, after treatment is complete.
In another aspect of the invention, a dialysis machine may include a fluid handling cassette having a plurality of spikes and a plurality of spike caps covering a respective spike, a plurality of solution lines each having a cap covering one connector end of the respective line and a cap separator arranged to remove one or more caps from one connector end of a solution line, and removing one or more spigot caps from a spike in the cassette while one or more caps are secured to one of the corresponding spigot caps. As described above, the machine may be arranged to automatically fluidly connect one end of the connector of a solution line to a corresponding spike after the caps are removed.
In another aspect of the invention, a dialysis machine, such as an APD system, may include a cassette having a plurality of fluid spikes and a plurality of spike caps covering a respective spike, a carriage arranged to receive a plurality of of solution lines each having a cap covering one connector end of the respective line and a cap separator arranged to engage one or more caps covering one connector end of a line. The carriage and cap separator can be configured to hook one or more caps to a connector end of a line while one or more caps are hooked with a corresponding spigot cap covering one spike in the cassette, and to remove the cap dowel pin and solution line connector end cap, and for fluidly connecting the dowel pin and solution line connector end after the caps are removed.
In another aspect of the invention, a dialysis machine may include a cap separator that is arranged to remove one or more caps at a connector end of a solution line, remove one or more pin caps from pins in a cassette of fluid handling, and retain and reattach the caps to the solution lines and the spigot caps to the spigots in the cassette.
In another aspect of the invention, a fluid line connection system for a peritoneal dialysis system includes a fluid handling cassette having a generally flat body with at least one pump chamber formed as a depression on a first side. of the body and a plurality of fluid flow paths, a plurality of dialysate solution line pins located at a first end of the body, solution line pins being in fluid communication with at least one pump chamber via at least one flow path and arranged such that the pins are generally co-planar with the generally flat body of the fluid handling cassette , and a cart arranged to receive a plurality of solution lines, where each solution line has a connector end. The carriage may be arranged to automatically fluidly connect one connector end of a solution line to a corresponding pin.
In one embodiment, the carriage is arranged to move the respective solution lines and caps along a first direction substantially parallel to the generally flat body of the fluid handling cassette. A carriage driver that moves the carriage in the first direction only may include a driver element and a pneumatic bladder or screw driver to move the driver element along the first direction. A cap separator can be provided which is arranged to remove one or more caps from a connector end of a solution line, and to remove one or more pin caps from a pin in the cassette while one or more caps are secured to a corresponding one of the spigot caps. In one embodiment, the cap separator may be arranged to retain and reattach the caps to the solution lines and the spigot caps to the spikes in the cassette.
In another aspect of the invention, a peritoneal dialysis system may include a cycling device with suitable components to control the delivery of dialysate to the peritoneal cavity of a patient. The cycler device may have a housing that encloses at least some of the components and has a heater bag receiving section. (The term "heater bag" is used here to refer to any suitable container for heating the dialysate, such as a flexible or rigid container, whether made of polymer, metal, or other suitable material). A lid may be mounted to the housing and be removable between an open position in which a heater bag can be placed in the heater bag receiving section and a closed position in which the lid covers the heater bag receiving section. Such an arrangement may allow faster or more efficient heating of dialysate in the heater bag, for example, because heat can be retained by the lid. Also, the lid can help prevent human contact from potentially hot surfaces.
In one embodiment, the dialysis system may include a fluid handling cassette with a heater bag port attached to a heater bag line, a patient port attached to a patient line, and at least one pump chamber for move fluid in the patient line and in the warmer bag line. A heater bag can be attached to the heater bag line and arranged for placement in the heater bag receiving section.
In another embodiment, the system may include an interface (such as a visual display with a touch screen component) that is movably mounted in the housing and is movable between a first position in which the interface is received in the section. heater bag receiver, and a second position in which the interface is located outside the heater bag receiver section (eg, a position in which a user can interact with the interface). Therefore, the interface can be hidden from view when the system is unloaded, allowing the interface to be protected. Also, storing the interface in the heater bag receiving section can make the system more compact, at least in an "as is stored" condition.
In another aspect of the invention, a dialysis system includes a pneumatic and / or vacuum pressure supply suitable for controlling pneumatically operated components of the system, a pneumatically operated component that is fluidly connected to the pneumatic and / or vacuum pressure supply, and a control system that provides pressure
<img file="MX2014005451A_D0004.tif" />
pneumatically or vacuum to the pneumatically operated component and subsequently isolates the pneumatically operated component from the pneumatic or vacuum pressure supply for a substantial period before again supplying pneumatic pressure or vacuum to the pneumatically operated component. Such an arrangement may be useful for components that are operated relatively infrequently, such as the occluder arrangement described herein. Small movements of some components can cause the component to emit noise that can be bothersome to the patient. By isolating the component from pneumatic / vacuum pressure, the component can prevent slight movements caused by variations in supply / vacuum pressure, for example, resulting from pressure / vacuum removal by other system components. In one embodiment, the substantial period may be 5 minutes or more, 1 hour or more, 50% or more of a period required to deliver or remove a volume of dialysate suitable for dialysis treatment with respect to the patient's peritoneal cavity or other suitable periods.
In another aspect of the invention, a dialysis system includes a pneumatic and / or vacuum pressure supply suitable for controlling pneumatically operated components of the system, a pneumatically operated component that is fluidly connected to the pneumatic and / or vacuum pressure supply, and a control system that supplies pneumatic pressure or vacuum to the pneumatically operated component and controls pneumatic pressure or vacuum to reduce noise generated by the pneumatically operated component. For example, the pneumatically operated component can include at least one moving part (such as a pump diaphragm) and the control system can reduce the pneumatic pressure or vacuum provided to the pneumatically operated component to slow down the movement of the moving part to As the moving part stops and / or changes direction (for example, pressure / vacuum can be controlled to slow down the movement of the diaphragm before the diaphragm changes direction). In another embodiment, a pulse width modulation control of a pressure / vacuum supply valve can be used, for example, to reduce noise emitted by moving parts of the valve.
In another aspect of the invention, a dialysis system includes a suitable pneumatic pressure and vacuum supply to control pneumatically operated components of the system. A pneumatically operated first component may be fluidly connected to the pneumatic and / or vacuum pressure supply, and have a first outlet line to release pneumatic pressure. A second pneumatically operated component may be fluidly connected to the pneumatic and / or vacuum pressure supply and have a second outlet line to release pneumatic vacuum. A space, such as that defined by an accumulator, manifold, or isolated sound chamber, can be fluidly connected to both the first output line and the second output line. A control system can supply pneumatic pressure or vacuum to pneumatically operated components so that when the first and second components release pressure / vacuum during operation, the pressure released / vacuum can be received in the common space (for example, a manifold) . In some circumstances, the gas under positive pressure released by components can be balanced by negative pressure released by other components, thus reducing the noise generated.
In another aspect of the invention, a peritoneal dialysis system may include a fluid handling cassette that has a patient line fluidly connected to and leading from a patient's peritoneal cavity, and that includes at least one pump chamber for move the dialysate solution on the patient line. A cycler device may be arranged to receive and interact with the fluid handling cassette and cause at least one pump chamber to move the dialysate solution in the patient line. The cycler may include a control system arranged to control at least one pump chamber to operate in an initiation operation to force the dialysate solution into the patient line to remove any air in the patient line, and may be adapted to interact with two types of fluid handling cassettes that differ with respect to a volume of the patient line connected to the cassette body. A first type of cassette may have a relatively low volume patient line (eg, for pediatric applications), and a second type of cassette may have a relatively high volume patient line (eg, for adult applications), and the
<img file="MX2014005451A_D0005.tif" />
The control system can detect whether a cassette received by the cycler is a first type or a second type and adjust the operation of the cycler accordingly.
In one embodiment, the control system can detect whether a cassette received by the cycler is a first type or a second type by determining the volume of the patient line during startup, and adjusting the amount of fluid moved through the cassette during system operation. In another embodiment, cues, such as a barcode, on the cassette can be detected by the cycler and cause the cycler to adjust a pump operation based on the type of cassette.
In another aspect of the invention, a dialysis machine includes a fluid handling cassette having a plurality of pins and at least one pump chamber for moving fluid on the pins, a plurality of solution lines each hooked with a respective spike on the cassette, and a control system that reads hints on each of the solution lines to determine a type for each of the solution lines. The control system can adjust a pumping operation or another cycler operation based on the identity of one or more of the solution lines. For example, a solution line can be identified as an effluent sampling line, and the pumping operation can be adjusted to direct used dialysate from a patient to the effluent sampling line during a drain cycle.
In another aspect of the invention, a method of automatic recovery from a tilted condition in a dialysis system may include (A) detecting a tilt angle of at least a portion of a dialysis system, the portion of the dialysis system including machinery for performing dialysis therapy, (B) determining that an inclined condition exists in which the angle of inclination exceeds a predetermined threshold, (C) in response to (B), pause dialysis therapy, (D) monitor the angle of inclination while dialysis therapy is paused, (E) determine that the inclined condition no longer exists, and (F) in response to (E), automatically resume dialysis therapy.
In another aspect of the invention, a patient data interface for a dialysis system includes a device port comprising a depression in a chassis of at least a portion of the dialysis system and a first connector disposed within the depression. A patient data storage device may include a housing and a second connector coupled to the housing, wherein the second connector is adapted to be selectively coupled to the first connector. The depression can have a first shape and the housing can have a second shape corresponding to the first shape such that when the first and second connectors are coupled, the patient data storage device housing is received at least partially inside of depression. The first and second forms may be irregular and the patient data storage device may have a verification code that is readable by the dialysis system to verify that the patient data storage device is of a type and / or origin. expected.
In another aspect of the invention, a method of providing peritoneal dialysis includes supplying or withdrawing dialysate with respect to the patient's peritoneal cavity at a first pressure, and adjusting a pressure at which the dialysate is delivered or withdrawn to minimize sensation. movement of the dialysate to the patient. In one embodiment, the pressure can be adjusted during the same fill or empty cycle of peritoneal dialysis therapy, and / or within different fill or empty cycles of peritoneal dialysis therapy. For example, when dialysate is withdrawn from a patient, the pressure at which the dialysate is withdrawn can be reduced when an amount of dialysate remaining in the peritoneal cavity falls below a threshold volume. Reducing pressure (negative pressure or vacuum) near the end of a drain cycle can reduce the patient's feeling of withdrawal from dialysate.
In another aspect of the invention, a method of providing peritoneal dialysis includes providing a first solution to the patient's peritoneal cavity using a reusable cycling device during a first peritoneal dialysis treatment, and providing a second solution to the patient's peritoneal cavity using the reusable cycling device during a second peritoneal dialysis treatment immediately after the first treatment, where the second solution has a different chemical constitution in relation to the first solution. Different solutions can be created by mixing liquid material from two or more solution containers that are connected to the cycler (eg, by a cassette mounted to the cycler). Solution containers can be automatically identified by the cycler, for example, by reading a barcode, RFID tag, or other clues.
In another aspect of the invention, a medical infusion system includes a housing that encloses at least some of the components of the system, and a control surface attached to the housing and constructed and arranged to control the operation of a fluid handling cassette. that it can be removably mounted to the housing. The control surface may have a plurality of movable portions arranged to control fluid pumping and valve operations of the cassette, and at least one of the movable portions may have an associated vacuum port arranged to withdraw fluid from a region near the movable portion.
In one embodiment, the control surface includes a sheet of elastic polymeric material, and each of the movable portions may have an associated vacuum port. In another embodiment, the cassette includes a membrane that can be positioned adjacent to the control surface, and the vacuum port is arranged to remove fluid from a space between the membrane and the control surface. A liquid detector may be arranged to detect liquid brought into the vacuum port, for example, in the event that the membrane breaks, allowing the liquid to leak out of the cassette.
In another aspect of the invention, a volume of fluid moved by a pump, such as a pump in an APD system, can be determined based on pressure measurement and certain known chamber and / or line volumes, but without direct measurement of the fluid, such as by flow meter, weight, etc. In one embodiment, a volume of a pump chamber having a movable element that varies the volume of the pump chamber can be determined by measuring the pressure in the pumping chamber, and a reference chamber when they are isolated from each other and after the two chambers are fluidly connected so that the pressures in the chambers can be equalized. In one embodiment, it can be assumed that pressure equalization occurs in an adiabatic way, for example, a mathematical model of the system that is based on an adiabatic pressure equalization process can be used to determine the volume of the pump chamber . In another embodiment, the pressures measured after the chambers are fluidly connected can be measured at a time before the termination of equalization has occurred, and thus the pressures for the pump and reference chambers measured after the chambers are fluidly connected can be uneven, but can be used to determine the volume of the pump chamber. This approach can reduce a time between the measurement of the initial and final pressures, thus reducing a time during which heat transfer can take place and reducing the error that can be introduced given the adiabatic model used to determine the chamber volume. pump.
In one aspect of the invention, a method of determining a volume of fluid moved by a pump includes measuring a first pressure for a pump control chamber when the pump control chamber is isolated from a reference chamber. The pump control chamber may have a volume that varies at least in part based on the movement of a portion of the pump, such as a diaphragm or pump diaphragm. A second pressure can be measured for the reference chamber when the reference chamber is isolated from the pump control chamber. The reference chamber may have a known volume. A third pressure associated with the pump control chamber can be measured after fluidly connecting the reference chamber and the pump control chamber, but the measurement can occur before substantial pressure equalization has occurred between the pump control and reference cameras. Similarly, a fourth pressure associated with the reference chamber after fluidly connecting the reference chamber and the pump control chamber can be measured, but before substantial pressure equalization has occurred between the control chambers. pump and reference. A volume for the pump control chamber can be determined based on the first, second, third, and fourth measured pressures.
In one embodiment, the third and fourth pressures are measured at approximately the same time and the third and fourth pressures are substantially unequal to each other. For example, the equalization of
<img file="MX2014005451A_D0006.tif" />
Pressures in the pump control and reference chambers can occur after an equalization period once the pump control and reference chambers are fluidly connected, but the third and fourth pressures can be measured at a later time. that the pump control and reference chambers are fluidly connected which is approximately 10% to 50% of the equalization period. Therefore, the third and fourth pressures can be measured long before (in the sense of time) that the pressures in the chambers are fully equalized. In another embodiment, the third and fourth pressures can be measured at a time when the pressures in the chambers have reached approximately 50-70% equalization, for example, the pressures in the chambers have changed from an initial value that is within approximately 50-70% of an equalized pressure value. Therefore, a period between the measurement of the first and second pressures and measurement of the third and fourth pressures can be minimized.
In another embodiment, a model for determining the volume of the pump control chamber may incorporate the assumption that an adiabatic system exists from a point of time when the first and second pressures are measured for the pump control chamber and chamber. reference to a point in time when the third and fourth pressures are measured.
To determine a volume of fluid moved by the pump, the measurement steps of the first, second, third, and fourth pressures and the determination step can be performed for two different positions of a pump membrane to determine two different volumes for the chamber. pump control. A difference between the two different volumes can represent a volume of fluid supplied by the pump.
As mentioned above, this aspect of the invention can be used in any suitable system, such as a system in which the pump is part of a disposable cassette and the pump control chamber is part of a dialysis machine used in a dialysis procedure.
In one embodiment, the first and / or second pressure can be selected from a plurality of pressure measurements as coinciding with a point in time at which a pressure in the pump control chamber or reference chamber (as appropriate) it first begins to change from a previously stable value. For example, the point in time can be identified based on a determination of when a best fit line for a plurality of consecutive sets of measured pressures first deviates from a constant slope. This approach can help identify baseline pressures for the pump control and reference chambers that are as late in time as possible, while reducing error in determining pump volume.
In another embodiment, a technique can be used to identify an optimum point in time at which the third and fourth pressures are measured.
For example, a plurality of pressure values for the pump control chamber can be measured after the pump control and reference chambers are fluidly connected, and a plurality of changes in volume values can be determined to the pump control chamber based on the plurality of pressure values for the pump control chamber. Each of the plurality of changes in volume values may correspond to a single point in time and a measured pressure value for the pump chamber. In this case, the change in volume values is due to the movement of an imaginary piston that is present in the valve or another component that initially isolates the control from the pump and the reference chambers, but moves after the valve is opened. or another component. Therefore, the pump chamber does not actually change in size or volume, but rather the change in volume is an imaginary condition due to the pressures in the pump chamber and reference chamber that are different from each other initially. Similarly, a plurality of pressure values for the reference chamber can be measured after the pump control and reference chambers are fluidly connected, and a plurality of changes in volume values can be determined for the chamber. of reference based on the plurality of pressure values for the reference chamber. Each of the plurality of changes in volume values may correspond to a single point in time and a measured pressure value for the reference chamber, and the same as the change in volume values for the pump chamber,
<img file="MX2014005451A_D0007.tif" />
they are a result of the movement of an imaginary piston. A plurality of difference values can be determined between the change in volume values for the pump control chamber and for the reference chamber, with each difference value being determined for the corresponding change in volume values for the pump chamber. pump control and the change in volume values for the reference chamber, i.e. the pairs of change in volume values for which a difference value is determined that corresponds to an equal or substantially equal point in time. Difference values can be analyzed, and a minimum difference value (or a difference value that is below a desired threshold) can indicate a point in time for which the third and fourth pressures should be measured. Thus, the third and fourth pressure values can be identified as equal to the pressure value of the pump control chamber and the reference chamber pressure value, respectively, corresponding to a difference value that is minimum or below of the threshold.
In another embodiment, the pressures measured are pressures of a gas within the pump control chamber and the reference chamber, equalization of pressures within the pump control chamber and reference chamber is assumed to occur adiabatically, equalization of pressures between the pump control chamber and reference chamber is assumed to include a change in the volume of a gas in the pump control chamber and reference chamber in equal but opposite directions, and the volume of gas in the reference chamber at the time of measurement of the fourth pressure is calculated from the known volume of the reference chamber, and the second and fourth pressures. The change in volume of gas in the reference chamber can be assumed to be the difference between the known volume of the reference chamber and the calculated value of the volume of gas in the reference chamber at the time of measurement of the fourth Pressure.
Also, the change in gas volume in the pump control chamber can be assumed as the difference between the initial volume of the pump control chamber and the volume of gas in the pump control chamber at the time of the third measurement. pressure, where the change in the volume of gas in the pump control chamber is equal to but opposite to the change in volume of gas in the reference chamber.
In another aspect of the invention, a method of determining a volume of fluid moved by a pump includes providing a fluid pump apparatus having a pump chamber separated from a pump control chamber by a movable membrane, and a chamber. Reference that is can be fluidly connected to the pump control chamber, adjust a first pressure in the pump control chamber to cause the membrane to move, and thus move the fluid in the pump chamber, isolate the reference chamber from the pump control chamber and establish a second pressure in the reference chamber that is different from a pressure in the pump control chamber, fluidly connect the reference chamber and the control chamber pump to initiate pressure equalization in the pump control chamber and reference chamber, and determine a volume for the pump control chamber based on the first and second pressures, and an assumption that the pressures in the pump control and reference chambers initiate equalization in an adiabatic way.
In one embodiment, the third and fourth pressures for the pump and reference control chambers, respectively, can be measured after fluidly connecting the reference chamber and the pump control chamber, and the third and fourth Pressures can be used to determine the volume for the pump control chamber. The third and fourth pressures can be substantially unequal to each other. In a similar way as mentioned above, adjustment, isolation, fluid connection, and determination steps can be repeated, and a difference between the two volumes determined for the pump control chamber can be determined, where the difference represents a volume of fluid supplied by the pump.
In another embodiment, the pump is part of a disposable cassette and the pump control chamber is part of a dialysis machine used in a dialysis procedure.
In another aspect of the invention, a medical infusion system includes a pump control chamber, a control surface associated with the pump control chamber so that at least a portion of the control surface is movable in response to a pressure change in the pump control chamber, a fluid handling cassette having at least one pump chamber located adjacent to the control surface and arranged such that the fluid in at least one pump chamber moves in response to movement of the portion of the surface of the control, a reference chamber that is fluidly connectable to the pump's control chamber, and a control system arranged to adjust a pressure in the pump control chamber and thus control fluid movement in the pump chamber of the fluid handling cassette. The control system may be arranged to measure a first pressure for the pump control chamber when the pump control chamber is isolated from the reference chamber, to measure a second pressure for the reference chamber when the reference chamber is isolated from the pump control chamber, fluidly connect the pump control chamber and the reference chamber, Measure third and fourth pressures associated with the pump control chamber and reference chamber, respectively, then fluidly connect the reference chamber and pump control chamber, and determine a volume for the pump control chamber with base on the first, second, third and fourth measured pressures and a mathematical model that defines pressure equalization in the pump and reference control chambers as occurs adiabatically when the pump and reference control chambers are fluidly connected.
In one embodiment, the third and fourth pressures are substantially unequal to each other, for example, the third and fourth pressures can be measured prior to the substantial equalization of pressures in the pump and reference control chambers.
In another aspect of the invention, a method of determining a volume of fluid moved by a pump includes measuring a first pressure for a pump control chamber when the pump control chamber is isolated from a reference chamber, the control chamber. pump having a volume that varies at least in part based on the movement of a portion of the pump, measure a second pressure for the reference chamber when the reference chamber is isolated from the pump control chamber, measure a third pressure associated with the pump control chamber and the reference chamber after fluidly connecting the pump chamber reference and pump control chamber, and determine a volume for the pump control chamber based on the first, second, and third measured pressures.
In one embodiment, the third pressure can be measured after complete pressure equalization in the pump control and reference chambers. In one embodiment, a model used to determine the volume of the pump chamber can adopt an adiabatic pressure equalization system between the pump chamber and the reference chamber.
In one aspect of the invention, a method of determining the presence of air in a pump chamber includes measuring a pressure for a pump control chamber when the pump control chamber is isolated from a reference chamber, the chamber control pump that has a known volume and that is separated from a pump chamber, which is at least partially filled with liquid, by a membrane, measure a pressure for the reference chamber when the reference chamber is isolated from the pump control chamber, the reference chamber having a known volume, measure a pressure after fluidly connecting the reference chamber and the control chamber check the pump and before a time when the pressure in the chambers has equaled, and determining the presence or absence of an air bubble in the pump chamber based on the known measured pressures and volumes.
In one embodiment, a model used to determine the presence or absence of an air bubble adopts an adiabatic system from a point in time when pressures are measured for the isolated pump control chamber and the reference chamber to a point in the time after the cameras are seamlessly connected. In another embodiment, the pressure for the pump control chamber is measured with the membrane drawn to a wall of the pump control chamber.
In another aspect of the invention, an automated peritoneal dialysis system includes a reusable cycler that is constructed and arranged for attachment to a disposable fluid handling cassette containing at least one pumping chamber. The disposable fluid handling cassette can be configured to be connected in fluid communication with a patient's peritoneum via a first collapsible tube and to a second source and / or destination (such as a solution container line) via a second collapsible tube . An occluder may be configured and located within the cycler to selectively occlude the first collapsible tube while not occluding the second collapsible tube. In one embodiment, the occluder can occlude a plurality of collapsible tubes, such as a patient line, a drain line, and / or a heater bag line. The cassette may have a generally flat body with at least one pump chamber formed as a depression on a first side of the body and a plurality of fluid flow paths, a patient line port located at a first end of the body arranged for connection to the first collapsible tube, and a solution line port located at a second end of the body opposite the first end, and arranged for connection to the second collapsible tube. The occluder may be configured and located within the cycler to selectively occlude the first tube and a third collapsible tube (eg, for a drain) while the second collapsible tube does not occlude.
In another embodiment, the occluder includes the first and second opposing occluder members pivotally connected to each other, a tube contact member connected to, or comprising at least a portion of, at least one of the first and second occluder members, and an actuator for Force constructed and positioned to apply a force to at least one of the first and second occluder members. The application of force by the force actuator can cause the tube contact members to move between a tube occlusion position and an open position. The occluder may include a release member configured and located to allow an operator to manually move the tube contact member from the tube occlusion position to the open position even without force applied to the occlusion member by the force actuator. The force actuator can apply enough force to bend both the first and second occlusion members, so that under the application of force by the force actuator to bend the first and second occlusion members, the contact member with the Tube can be moved between a tube occlusion position and an open position. The occlusion members may be spring plates pivotally connected together at opposite first and second ends, and the tube contact member may be a clamp head connected to spring plates at the first ends, while the second ends The spring plates can be attached directly or indirectly to a housing to which the occluder is connected. In one embodiment, the force actuator comprises an inflatable bladder located between the first and second occlusion members. The force actuator can increase a distance between the first and second occlusion members in a region where the first and second occlusion members are in opposition to move the tube contact member between a tube occlusion position and a position open. In one embodiment, the force actuator may bend one or both of the occlusion members to move the tube contact member from a tube occlusion position to an open position.
Various aspects of the invention have been described above and are described below with reference to illustrative embodiments. It should be understood that the various aspects of the invention can be used alone and / or in any suitable combination with other aspects of the invention. For example, determination of the pump volume characteristics described here can be used with a liquid handling cassette having the specific characteristics described, or with any other suitable pump configuration.
BRIEF DESCRIPTION OF THE FIGURES
Aspects of the invention are described below with reference to illustrative embodiments which are shown, at least in part, in the following figures, in which like numbers refer to like elements, and wherein:
Figure 1 shows a schematic view of an automated peritoneal dialysis (APD) system incorporating one or more aspects of the invention;
Figure 1A shows an alternative arrangement for a dialysate supply assembly shown in Figure 1;
Figure 2 is a schematic view of an illustrative assembly for use with the APD system of Figure 1;
Figure 3 is an exploded perspective view of a cassette in a first embodiment;
Figure 4 is a cross-sectional view of the cassette along line 4-4 in Figure 3;
Figure 5 is a perspective view of a vacuum mold that can be used to form a membrane having pre-formed pump chamber portions in an illustrative embodiment;
Figure 6 shows a front view of the body of the cassette of Figure 3;
Figure 7 is a front view of a cassette body including two different spacer arrangements in an illustrative embodiment;
Figure 8 is a rear perspective view of the body of the cassette of Figure 3;
Figure 9 is a rear view of the body of the cassette of Figure 3;
Figure 9-1A is a front perspective view of an exemplary configuration of a patient line status detector or liquid level detector;
Figure 9-1B is a rear perspective view of a patient line status detector or liquid level detector;
Figure 9-2 is a perspective plan view of three LEDs and a surface of the optical detector mounted on a printed circuit board;
Figure 9-3 is a plan view of three LEDs and an optical detector mounted on a detector circuit board;
Figure 9-4 is an exploded perspective view of the detector of Figures 9-1 A, 9-1B showing the printed circuit board and a transparent or translucent plastic insert.
Figure 9-5 is a perspective view of an alternative configuration of a liquid level detector;
Figure 9-6 is a perspective view of the front of an unloaded organizer (any solution lines absent);
Figure 9-7 is a rear view of the organizer of Figure 9-6;
Figure 9-8 is a perspective view of an organizer including a plurality of solution lines, a patient line, and a drain line;
Figure 9-9 is a perspective view of a clip on the organizer;
Figure 9-10 is a perspective view of an organizer clip receiver;
Figure 9-11 is a perspective view of a door latch detector assembly related to a cycler;
Figure 9-11A is a cross-sectional view of the door latch detector assembly of Figure 9-11;
Figure 9-12 is a graph showing the ability of the liquid level detector of Figures 9-1 A, 9-1B to distinguish between an initiated and an uninitiated patient line;
Figure 9-12A is a graph showing the signal range for a started and uninitiated patient line for different cyclists using the liquid detector of Figures 9-1A and 9-1B.
Figure 9-13 is a graph showing measurements collected by an optical detector comparing liquid detection using an LED orthogonally oriented against an angular LED;
Figure 9-14 is a graph showing the ability of the liquid level detector of Figures 9-1 A, 9-1B to distinguish between the presence and absence of a segment of the tube within the detector;
Figure 10 is a perspective view of the APD system of Figure 1 with the cycler door in an open position;
Figure 11 is a perspective view of the inner side of the cycler door shown in Figure 10;
Figure 11-1 is a perspective view of a carriage in a first embodiment;
Figure 11-2 is an elongated perspective view of a solution line loaded on the cart of Figure 11-1;
Figure 11-3 is a perspective view of an open identification tag;
Figure 11-4 is a perspective view of a car driver assembly that includes an AutoID camera mounted on a dash of the AutoID camera;
Figure 11-5 is a perspective view of one embodiment for a spacer element of a cap spacer;
Figure 11-6 is a front perspective view of the carriage driver assembly of Figure 11-4 showing the position of the spacer element of Figure 11-5 within the carriage driver assembly;
Figure 11-7A shows a perspective view of a portion of the spacer element of Figure 11-5, where a dowel cap is placed;
Figure 11-7B shows a perspective view of a portion of the spacer element of Figure 11-5, where a solution line cap is placed on the spigot cap;
Figure 11-7C shows a perspective view of a portion of the spacer element of Figure 11-5, showing a sensing element and an oscillating arm in the absence of a spigot cap;
Figure 12 is a right front perspective view of a carriage driver assembly and cap separator in a first embodiment;
Figure 13 is a left front perspective view of the carriage driver assembly and cap separator of Figure 12;
Figure 14 is a partial rear view of the carriage driver assembly of Figure 12;
Figure 15 is a rear perspective view of a carriage driver assembly in a second illustrative embodiment;
Figure 16 is a left rear perspective view of the carriage driver assembly and cap separator of Figure 15;
Figure 17 is a left front perspective view of a lid separator element in an illustrative embodiment;
Figure 18 is a right front perspective view of the lid separating element of Figure 17;
Figure 19 is a front view of the lid separating element of Figure 17;
Figure 20 is a cross sectional view along line 20-20 in Figure 19;
Figure 21 is a cross-sectional view along line 21-21 in Figure 19;
Figure 22 is a cross-sectional view along line 22-22 in Figure 19;
Figure 23 is an exploded close-up view of the connector end of a solution line in an illustrative embodiment;
Figure 24 is a schematic view of a cassette and solution lines that are loaded into the cycler of Figure 10;
Figure 25 is a schematic view of the cassette and solution lines after being placed at respective locations on the door of the cycler of Figure 10;
Figure 26 is a schematic view of the cassette and solution lines after the cycler door is closed;
<img file="MX2014005451A_D0008.tif" />
Figure 27 is a schematic view of the solution lines that are hooked with dowel caps;
Figure 28 is a schematic view of the cap separator engaging with spigot caps and solution caps;
Figure 29 is a schematic view of the solution lines with attached caps and spigot caps after moving the cassette away;
Figure 30 is a schematic view of the solution lines after moving away from the solution line caps and spigot caps;
Figure 31 is a schematic view of the cap separator that retracts with solution line caps and dowel caps;
Figure 32 is a schematic view of the solution lines being hooked onto the pins of the cassette;
Figure 33 is a cross-sectional view of a cassette with five stages of a solution line connecting operation shown with respect to corresponding pins on the cassette;
Figure 34 shows a rear view of a cassette in another illustrative embodiment that includes different arrangements for a rear side of the cassette adjacent to the pump chambers;
Figure 35 shows an end view of a spike of a cassette in an illustrative embodiment;
Figure 35A shows a perspective view of an alternative embodiment of the pins on a cassette;
Figure 35B shows one embodiment of a spigot cap configured to fit over the spikes shown in Figure 35A;
Figure 35C shows a cross sectional view of a dowel cap shown in Figure 35B;
Figure 36 shows a front view of a cycler control surface for interaction with a cassette in the embodiment of Figure 10;
Figure 36A shows a front view and selected cross-sectional views of one embodiment of a cycler control surface;
Figure 37 shows an exploded view of an assembly for the Interface surface of Figure 36, with the coupling pressure supply block and the pressure distribution module;
Figure 37A shows an exploded view of the integrated manifold;
Figure 37B shows two isometric views of the integrated manifold;
Figure 37C shows a schematic of the pneumatic system that controls the flow of fluid through the cycler;
Figure 38 shows an exploded perspective view of an occluder in an illustrative embodiment;
Figure 39 shows a partially exploded perspective view of the occluder of Figure 38;
Figure 40 shows a top view of the occluder of the Figure with the bladder in a deflated state;
Figure 41 shows a top view of the Figure occluder with the bladder in an inflated state;
FIG. 42 is a schematic view of a cassette pump chamber and associated control components and inbound / outflow paths in an illustrative embodiment;
Figure 43 is a graph of illustrative pressure values for the control chamber and reference chamber from one point in time before valve X2 opens to some time after valve X2 opens for the embodiment of Figure 42;
Figure 44 is a perspective view of an inner section of the cycler of Figure 10 with the upper portion of the housing removed;
Figure 45 is a schematic block diagram illustrating an exemplary implementation of the control system for an APD system;
Figure 45A is a schematic block diagram illustrating an exemplary arrangement of the multiple processors that control the cycler and the secure line;
Figure 45B is a schematic block diagram illustrating exemplary connections between the hardware interface processor and detectors, actuators, and the automation computer;
Figure 46 is a schematic block diagram of illustrative software subsystems of a user interface computer and the automation computer for the control system of Figure 45;
Figure 47 shows an information flow between various subsystems and APD system processes in an illustrative embodiment;
Figure 48 illustrates an operation of the therapy subsystem of Figure 46;
Figure 49 shows a sequence diagram illustrating exemplary interactions of therapy module processes during initial fill and dialysis portions of therapy;
Figure 49-1 shows a schematic cross section of the cycler illustrating the components of the heater system for the heater bag;
Figure 49-2 shows the software processes that interact with the heater controller process;
Figure 49-3 shows the block diagram of a nested feedback loop to control the temperature of the heater bag;
Figure 49-4 shows the block diagram of a nested feedback loop to control the temperature of the heater bag;
Figure 49-5 shows the block diagram of another alternative nested feedback loop to control the temperature of the heater bag;
Figure 49-6 shows the thermal model block diagram of the heater bag and heater tray;
Figure 49-7 shows the temperature response of the heater bag and heater tray for nominal conditions;
Figure 49-8 shows the temperature response of the heater bag and heater tray for hot conditions;
Figure 49-9 shows the temperature response of the heater bag and heater tray for cold conditions;
Figure 49-10 is a schematic block diagram of one embodiment of a heater control system;
Figure 49-11 is a schematic block diagram illustrating a heater circuit configured with a pair of heating elements;
Figure 49-12 is a schematic block diagram illustrating a heater circuit configured with a pair of heating elements with reduced potential for current leakage;
Figure 49-13 is a circuit diagram of a heater circuit configured with a pair of heating elements;
Figure 49-14 shows a flowchart illustrating a method for selecting the heater configuration on an APD cycler, in accordance with one embodiment of the present invention; and
Figure 49-15 shows a flowchart illustrating a method for selecting the heater setting on an APD cycler where a stored value of the main AC voltage is questioned during selection of the heater setting, in accordance with one embodiment of the present invention.
Figures 50-55 show illustrative screen views related to alerts and alarms that can be displayed on a Touch Screen User Interface for the APD system;
Figure 56 illustrates component states and operations for error condition detection and recovery in an illustrative embodiment;
Figure 57 shows exemplary modules of an Ul view subsystem for the APD system;
Figures 58-64 show illustrative user interface screens to provide user information and receive user input in illustrative modalities regarding system setup, therapy status, deployment values, remote assistance, and parameter values;
Figure 65 shows an exemplary patient data key and associated port for transferring patient data to and from the APD system;
Figure 65A shows a patient data key with an alternative housing configuration.
Figure 66 shows an exemplary pressure trace of a control chamber or actuation of a pump cassette during a liquid supply blow;
Figure 67 shows an illustration of a mode of physiological variation therapy during CCPD;
Figure 68 shows an illustration of the implementation of a revised cycle mode during CCPD;
Figure 69 shows an illustration of the implementation of a revised cycle mode during physiological variation therapy; and
Figure 70 shows an illustration of the implementation of an adaptive physiological variation mode during physiological variation therapy.
DETAILED DESCRIPTION OF THE INVENTION
Although aspects of the invention are described in connection with a peritoneal dialysis system, certain aspects of the invention can be used in other medical applications, including infusion systems such as intravenous infusion systems or extracorporeal blood flow systems, and irrigation and / or fluid exchange systems for the stomach, intestinal tract, urinary bladder, pleural space, or other body or organ cavity. Therefore, aspects of the invention are not limited to use in peritoneal dialysis in particular, or dialysis in general.
APD system
Figure 1 shows an automated peritoneal dialysis (APD) system 10 that can incorporate one or more aspects of the invention. As shown in Figure 1, for example, system 10 in this illustrative embodiment includes a dialysate supply set 12 (which, in certain embodiments, may be a disposable set), a cycler 14 that interacts with the supply set 12 for pumping liquid provided by a solution container 20 (eg, a bag), and a control system 16 (eg, including a programmed computer or other data processor, computer memory, an interface to provide information to and receive input from a user or other device, one or more detectors, actuators, relays, pneumatic pumps, tanks, a power supply, and / or other suitable components - just a few buttons to receive input from the control User instructions are shown in Figure 1, but additional details regarding the control system components are provided below) that govern the process for performing an APD procedure. In this illustrative embodiment, cycler 14 and control system 16 are associated with a housing 82, but may be associated with two or more housings and / or may be separate from each other. Cycler 14 can have a compact footprint, suitable for operation on a table or other relatively small surface normally found in the home. Cycler 14 may be lightweight and portable, for example, hand-carried by handles on opposite sides of housing 82.
The assembly 12 in this embodiment is intended to be a single-use disposable article, but may rather have one or more reusable components, or may be reusable in its entirety. The user associates assembly 12 with cycler 14 before beginning each APD therapy session, for example, by mounting cassette 24 within front door 141 of cycler 14, which interacts with cassette 24 to pump and control the flow of fluid in the various lines of set 12. For example, the dialysate can be pumped both to and from the patient to perform APD. After therapy, the user may remove all or part of the components from assembly 12 of cycler 14.
As is known in the art, prior to use, the user may connect a line of patient 34 from assembly 12 to their internal peritoneal catheter (not shown) in a connection 36. In one embodiment, cycler 14 may be configured to operate with one or more different types of cassettes 24, such as those with patient lines of different sizes 34. For example, cycler 14 may be arranged to operate with a first type of cassette with a patient line 34 sized for use with an adult patient, and a second type of cassette with a patient line 34 sized for use in young children or pediatric. The pediatric patient line 34 can be shorter and have a smaller internal diameter than the adult line to minimize the volume of the line,
<img file="MX2014005451A_D0009.tif" />
allowing for a more controlled supply of dialysate and helping to avoid returning to a relatively large volume of dialysate used for the pediatric patient when assembly 12 is used for consecutive drain and fill cycles. A heater bag 22, which is connected to cassette 24 by a line 26, can be placed in a receiving portion of the heater container (in this case, a tray) 142 of cycler 14. Cycler 14 can pump fresh dialysate (via cassette 24) into heater bag 22 so that dialysate can be heated by means of heater tray 142, for example, by means of electrical resistance heating elements associated with tray 142 at a temperature of approximately 37 ° C. The heated dialysate can be provided from the heater bag 22 to the patient via cassette 24 and patient line 34. In an alternative embodiment, the dialysate may be heated on its way to the patient as the cassette 24 enters, or after it exits, by passing the dialysate through the tube in contact with the heater tray 142, or through a in-line fluid heater (which can be supplied in cassette 24). The used dialysate can be pumped from the patient via the patient line 34 to the cassette 24 and into a drain line 28, which may include one or more clamps to control flow through one or more branches of the drain line 28. In this illustrative embodiment, drain line 28 may include a connector 39 for connecting drain line 28 to a dedicated drain receptacle, and an effluent sample port 282 for taking a sample of dialysate used for testing or other analysis. The user may also mount lines 30 of one or more containers 20 within door 141. Lines 30 may also be connected to a continuous or real-time dialysate preparation system. (Lines 26, 28, 30, 34 may include a suitable hose and / or connectors and other components (such as shrink valves, etc.) as desired.) Containers 20 may contain sterile peritoneal dialysis solution for infusion. , or other materials (eg, materials used by cycler 14 to formulate dialysate by mixing with water, or by mixing different types of dialysate solutions). Lines 30 may be connected to pins 160 of cassette 24, shown in Figure 1 covered by removable caps. In an aspect of the invention described in more detail below, cycler 14 can automatically remove caps from one or more pins 160 from cassette 24 and connect lines 30 of solution containers 20 to respective pins 160. This feature can help reduce the possibility of infection or contamination by reducing the likelihood of non-sterile items contacting spikes 160.
In another aspect, a dialysate supply assembly 12a may not have spigots from cassette 160. Instead, one or more solution lines 30 can be permanently attached to the inlet ports of cassette 24, as shown in Figure 1A. In this case, each solution line 30 may have a spigot (capped) connector 35 for manual connection to a solution container or dialysate bag 20.
With various connections made, control system 16 can mark the passage of cycler 14 through a series of fill, residence, and / or drain cycles typical of an APD procedure. For example, during a fill phase, cycler 14 can pump dialysate (via cassette 24) from one or more containers 20 (or other dialysate supply source) into heater bag 22 for heating. Subsequently, cycler 14 can infuse heated dialysate from heater bag 22 through cassette 24 and into the patient's peritoneal cavity via patient line 34. After a residency phase, cycler 14 may institute a drain phase, during which cycler 14 pumps used dialysate from the patient via line 34 (again via cassette 24), and discharges spent dialysis solution into a drain close (not shown) via drain line 28.
Cycler 14 does not necessarily require that solution containers 20 and / or heater bag 22 be located at a prescribed head height above cycler 14, for example, because cycler 14 is not necessarily a gravity flow system . Instead, cycler 14 can emulate gravity flow, or otherwise adequately control the flow of dialysate solution, even with solution containers 20 above, below, or at the same height as cycler 14, with the patient above or below the cycler, etc. For example, cycler 14 can emulate a fixed head height during a given procedure, or cycler 14 can change the effective head height, either to increase or decrease the pressure applied to the dialysate during a procedure. Cycler 14 can also adjust the dialysate flow rate. In one aspect of the invention, cycler 14 can adjust the dialysate flow pressure and / or flow rate when supplied to the patient or withdrawn from the patient to reduce the patient's sensation of the filling or draining operation. Said adjustment can occur during a single fill and / or drain cycle, or it can be adjusted through different fill and / or drain cycles. In one embodiment, cycler 14 can taper the pressure used to extract used dialysate from the patient near the end of a drain operation. Because cycler 14 can establish an artificial head height, it can have the flexibility to interact with and adapt to particular physiology or changes in the patient's relative elevation.
Cassette
In one aspect of the invention, a cassette 24 can include patient and drain lines that are separately occludable from solution supply lines. That is, the critical safe flow to and from the patient line can be controlled, for example, by squeezing the lines to stop the flow, without the need to occlude the flow through one or more solution supply lines. This feature may allow for a simplified occluder device since occlusion can be performed with respect to only two lines as opposed to occluding other lines that have little or no effect on patient safety. For example, in a circumstance where a patient or drain connection is disconnected, the patient and drain lines may be occluded. However, the supply of solution lines and / or heater bag may remain open for flow, allowing cycler 14 to prepare for an upcoming dialysis cycle; for example, the separate occlusion of patient and drain lines can help ensure patient safety while allowing cycler 14 to continue pumping dialysate from one or more containers 20 to warmer bag 22 or other solution containers 20.
In another aspect of the invention, the cassette may have patient lines, drain, and warmer bag on one side or portion of the cassette and one or more solution supply lines on another side or portion of the cassette, eg, an opposite side. of the cassette. Such an arrangement may allow separate occlusion of the patient lines, drain, or warmer bag from solution lines as described above. The physical separation of lines attached to the cassette by type or function allows more efficient interaction control with lines of a certain type or function. For example, such an arrangement may allow for a simplified occluder design because less force is required to occlude one, two, or three of these lines than all lines leading to or away from the cassette. Alternately, this arrangement may allow for more effective automated connections from solution supply lines to the cassette, as described in more detail below. That is, with solution supply lines and their respective connections located apart from the patient, drain, and / or heater bag lines, an automated cap and uncap device can remove caps from the pins on the cassette as well as caps on solution supply lines, and connect the lines to respective pins without interference by the patient lines, drain, or warmer bag.
Figure 2 shows an illustrative embodiment of a cassette 24 incorporating aspects of the invention described above. In this embodiment, cassette 24 has a generally flat body, and heater bag line 26, drain line 28, and patient line 34 are connected at respective ports on the left end of the cassette body, while the end Right side of the cassette body may include five dowels 160 to which the solution supply lines 30 may be connected. In the arrangement as shown in Figure 2, each of the spikes 160 is covered by a spike cap 63, which can be removed, exposing the respective spike and allowing connection to a respective line 30. As described above, lines 30 may be attached to one or more solution containers or other material sources, for example, for use in dialysis and / or dialysate formulation, or connected to one or more collection bags for purposes sampling or for peritoneal balance test (PET test).
Figures 3 and 4 show exploded views (perspective and top views, respectively) of cassette 24 in this illustrative embodiment. Cassette 24 is formed as a relatively thin, flat member having a generally flat shape, for example, it may include components that are molded, extruded, or otherwise formed of a suitable plastic. In this embodiment, cassette 24 includes a base member 18 that functions as a frame or structural member for cassette 24, as well as to form, at least in part, various fluid channels, ports, valve portions, etc. Base member 18 can be molded or otherwise formed from a suitable plastic or other material, such as a polymethyl methacrylate acrylic (PMMA), or an ultra low density cyclic olefin / polyethylene copolymer (COC / ULDPE), and it can be relatively stiff. In one embodiment, the COC to ULDPE ratio may be approximately 85% / 15%. Figure 3 also shows the ports for the heater bag (port 150), drain (port 152) and the patient (port 154) that are formed in the base member 18. Each of these ports can be arranged in any suitable way , such as, for example, a center tube 156 extending from an outer ring or skirt 158, or a center tube alone. The flexible tube for each of the drained, patient, and heater bag lines 26, 28, 34 may be connected to the central tube 156 and hooked by the outer ring 158, if present.
Both sides of base member 18 may be covered, at least in part, by a membrane 15 and 16, for example, a flexible polymer film made of, for example, polyvinyl chloride (PVC), which is cast, extruded, or otherwise formed. Alternatively, the sheet may be formed as a laminar unit of two or more layers of poly-cyclohexylene dimethylene cyclohexanedicarboxylate (PCCE) and / or ULDPE, held together, for example, by a coextrudable adhesive (CXA). In some embodiments, the thickness of the membrane can be in the range of about 0.00508 to 0.0508 cm thick. In a preferred embodiment, the thickness of a PVC-based membrane can be in the range of about 0.030 to 0.040 cm thick, and most preferably about 0.035 cm thick. In another preferred embodiment, such as for laminated sheets, the thickness of the sheet unit may be in the range of about 0.015 to 0.025 cm thick, and most preferably about 0.020 cm thick.
Both membranes 15 and 16 can function not only to close or otherwise form a part of the flow paths of cassette 24, but can also be moved or otherwise manipulated to open / close valve ports and / or to function as part of a diaphragm, septum, or pump wall that moves fluid in cassette 24. For example, membranes 15 and 16 may be located on base member 18 and sealed (eg, by heat, adhesive, ultrasonic welding, or other means) to a flange around the periphery of base member 18 to prevent fluid from leaked from cassette 24. The membrane 15 may also be bonded to other interior walls of base member 18, for example, those that form multiple channels, or may be pressed into sealed contact with the walls and other characteristics of base member 18 when cassette 24 is suitably mounted on cycler 14. Therefore, both of the membranes 15 and 16 may be sealed to a peripheral rim of the base member 18, for example, to help prevent fluid leakage from cassette 24 when removed from cycler 14 after use, but are arranged to lie, unattached, on other portions of the base member 18. Once placed in cycler 14, cassette 24 can be crushed between opposing gaskets or other members such that membranes 15 and 16 are pressed into sealing contact with base member 18 in regions within the periphery, thus properly sealing the channels, valve ports, etc., from each other.
Other arrangements for membranes 15 and 16 are possible. For example, the membrane 16 may be formed of a rigid sheet of material that is attached or otherwise made integral with the body 18. Therefore, the membrane 16 need not be, or include, a flexible member. Similarly, membrane 15 need not be flexible over its entire surface, but may instead include one or more flexible portions to allow operation of the pump and / or valve, and one or more rigid portions, for example, to close cassette flow paths 24. It is also possible that cassette 24 may not include membrane 16 or membrane 15, for example, where cycler 14 includes a member suitable for sealing the paths of the cassette, control valve, and pump function, etc.
<img file="MX2014005451A_D0010.tif" />
In accordance with another aspect of the invention, the membrane 15 may include a pump chamber portion 151 (pump membrane) that is formed to have a configuration that closely conforms to the configuration of a corresponding pump chamber depression 181 in base 18. For example, membrane 15 can generally be formed as a flat member with thermoformed (or otherwise formed) dome-like configurations 151 that conform to the base member pump chamber depressions 18. The dome-like configuration of preformed pump chamber portions 151 can be constructed, for example, by heating and forming the membrane on a vacuum-shaped mold of the type shown in Figure 5. As shown in Figure 5, the vacuum can be applied through a collection of holes along the wall of the mold. Alternatively, the mold wall can be constructed of a porous gas permeable material, which can result in a more uniformly smooth surface of the molded membrane. In one example, the molded membrane sheet 15 is trimmed while attached to the mold in a vacuum fashion. The vacuum form mold then presses the cut membrane sheet 15 against the cassette body 18 and binds them together. In one embodiment, the membrane sheets 15, 16 are heat welded to the cassette body 18. In this way, the membrane 15 can be moved relative to the pump chambers 181 to effect the pumping action without requiring stretching of the membrane 15 (or at least minimal stretching of the membrane 15), when the membrane 15 is moved to the maximum towards the pump chambers 181 and (potentially) in contact with the separator elements 50 (for example, as shown in the solid line in Figure 4 while fluid is pumped out of the pump chamber 181), and when membrane 15 is fully withdrawn from pump chamber 181 (eg, as shown in broken line in Figure 4 when fluid is drawn into pump chamber 181). Avoiding stretching of the membrane 15 can help prevent overvoltages or other changes in fluid supply pressure due to sheet stretching and / or help simplify pump control when seeking to minimize pressure variation during pumping operation. Other benefits can be found, including reduced probability of failure of membrane 15 (eg, due to tears in membrane 15 resulting from stresses placed on membrane 15 during stretching), and / or improved accuracy in volume measurement pump supply, as described in more detail below. In one embodiment, portions of pump chamber 151 can be formed to have a size (eg, to define a volume) that is approximately 85-110% of pump chamber 181, for example, if portions of pump pump chamber 151 define a volume that is approximately 100% of the volume of the pump chamber, the portions of the pump chamber 151 can be laid in the pump chamber 181 and in contact with the spacers 50 while at rest and without being stressed.
Providing greater control of the pressure used to generate a filling and liquid supply blow into and out of a pump chamber can have several advantages. For example, it may be desirable to apply the minimum possible negative pressure when the pump chamber draws fluid from the patient's peritoneal cavity during a drain cycle. A patient may experience discomfort during the drain cycle of a treatment in part due to the negative pressure that is applied by the pumps during a fill stroke. The added control that a preformed membrane can provide to the negative pressure that is applied during a fill stroke can help reduce patient discomfort.
Many other benefits can be realized by using preformed pump membranes to contour the cassette pump chamber. For example, the flow rate of the liquid through the pump chamber can be made more uniform, because a constant pressure or vacuum can be applied throughout the stroke of the pump, which in turn can simplify the process of regulate the heating of the liquid. Furthermore, temperature changes in the cassette pump may have a minor effect on the displacement dynamics of the membrane, as well as the accuracy of pressure measurements within the pump chambers. In addition, the pressure pins within the fluid lines can be minimized. Also, the correlation of the pressure measured by pressure transducers on the control (eg pneumatic) side of the membrane with the actual pressure of the liquid on the pump chamber side of the membrane may be simpler. This in turn can allow for more accurate patient head height and fluid source bag measurements prior to therapy, improve the sensitivity of air detection in the pump chamber, and improve the accuracy of volumetric measurements. Furthermore, eliminating the need to stretch the membrane can allow the construction and use of pump chambers that have higher volumes.
In this embodiment, cassette 24 includes a pair of pump chambers 181 that are formed on base member 18, although one pump chamber or more than two pump chambers are possible. In accordance with one aspect of the invention, the interior wall of pump chambers 181 includes spacer elements 50 that are spaced apart from each other and extend from the interior wall of pump chamber 18 to help prevent portions of the membrane 15 make contact with the interior wall of the pump chamber 181. (As shown in the right-side pump chamber 181 in Figure 4, the inner wall is defined by the side portions 181a and a bottom portion 181b. The spacers 50 extend upward from the bottom portion 181b in this embodiment, but could extend from the side portions 181a or be formed in other ways.) By preventing contact of the membrane 15 with the interior wall of the chamber of bomb, separator elements 50 can provide a dead space (or trap volume) that can help trap air or other gas in pump chamber 181 and inhibit gas from being pumped out of pump chamber 181 in some circumstances. In other cases, spacers 50 can assist gas to move to an outlet of pump chamber 181 so that gas can be removed from pump chamber 181, for example, during initiation. Also, spacers 50 can help prevent membrane 15 from sticking to the interior wall of pump chamber and / or allow flow to continue through pump chamber 181, even when membrane 15 is pressed into contact. with spacer elements 50. In addition, spacers 50 help prevent premature closure of the pump chamber outlet port (openings 187 and / or 191) if the sheet contacts the interior wall of the pump chamber in a non-uniform manner. Additional details regarding the arrangement and / or function of the spacers 50 are provided in US Patents 6,302,653 and 6,382,923, both of which are incorporated herein by reference.
In this embodiment, the spacer elements 50 are arranged in a type of stadium seating arrangement such that the spacer elements 50 are arranged in a concentric elliptical pattern with ends of the spacer elements 50 increasing in height from the lower portion 181b of the inner wall away from the center of the pump chamber 181 to form a semi-elliptical dome configuration region (shown by dotted line in Figure 4). The location of the spacer elements 50 such that the ends of the spacer elements 50 form a semi-elliptical region defining the dome region designed to be swept by portions of the pump chamber 151 of the membrane 15 can allow for a Desired dead space volume that minimizes any reduction to the intended bump capacity of pump chambers 181. As can be seen in Figure 3 (and Figure 6), the stadium seating arrangement in which the spacer elements 50 are arranged may include aisles or breaks 50a in the elliptical pattern. The breaks (or aisles) 50a help maintain an equal gas level along the rows (voids or dead space) 50b between separator elements 50 as the fluid is supplied from the pump chamber 181. For example, if the spacer elements 50 were arranged in the stadium seating arrangement shown in Figure 6 without breaks (or aisles) 50a or other means to allow liquid and air to flow between the spacer elements 50, the membrane 15 could reach the lowest point in the separator element 50 located in the outermost periphery of the pump chamber 181, trapping any gas or liquid that is present in the gap between this outermost spacer element 50 and the side wall portions 181a of the pump chamber. Similarly, if the membrane 15 reaches the lowest point in any two adjacent spacer elements 50, any gas and liquid in the gap between the elements 50 can be trapped. In such an arrangement, at the end of the pump stroke, air or other gas in the pump chamber center 181 could be supplied while the liquid remains in the outer rows. Supplementing breaks (or passages) 50a or other fluid communication means between the gaps between spacer elements 50 helps to maintain an equal gas level along the gaps during the pump stroke, such that air or other Gas can be inhibited from leaving pump chamber 181 unless the volume of liquid has been substantially supplied.
In certain embodiments, spacer elements 50 and / or membrane 15 may be arranged such that membrane 15 generally does not wrap or otherwise deform around individual spacers 50 when pressed in contact with them, or otherwise they extend significantly into the gaps between the spacers 50. Such an arrangement can reduce any stretch or damage to the membrane 15 caused by wrapping or otherwise deforming around one or more individual spacer elements 50. For example, it has also been found to be advantageous in this embodiment to size the gaps between spacers 50 approximately equal in width to the width of spacers 50. This feature has been shown to help prevent deformation of the membrane 15, eg, sagging of the membrane in the gaps between spacers 50, when the membrane 15 is forced into contact with the spacers 50 during a pumping operation.
In accordance with another aspect of the invention, the inner wall of the pump chambers 181 can define a depression that is greater than the gap, for example a semi-elliptical or dome gap, designed to be swept by the chamber portions. diaphragm pump 151. In such cases, one or more spacer elements 50 may be located below the dome region designed to be swept by the membrane portion 151 rather than extending within that dome region. In certain cases, the ends of spacer elements 50 can define the periphery of the dome region designed to be swept by membrane 15. The location of the spacer elements 50 outside, or adjacent to, the periphery of the dome region designed to be swept by the membrane portion 151 can have a number of advantages. For example, the location of one or more spacer elements 50 such that the spacer elements are outside of, or adjacent to, the dome region designed to be swept by the flexible membrane provides a dead space between the spacers and the membrane, as described above, while minimizing any reduction to the designed striking capacity of the pump chambers 181.
It should be understood that the spacer elements 50, if present, in a pump chamber can be arranged in any other suitable way, as, for example, shown in Figure 7. (The pump chamber 181 on the left-hand side in Figure 7 includes spacers 50 arranged similarly to that of Figure 6, but there is only one break or passageway 50a running vertically through the approximate center of pump chamber 181. Spacers 50 can be arranged to define a concave shape similar to that of Figure 6 (i.e., the tops of spacers 50 can form the semi-elliptical shape shown in Figures 3 and 4), or can be arranged in other suitable means, such as to form a spherical shape, a box shape and so on. The right side pump chamber 181 in Figure 7 shows an embodiment in which the spacers 50 are vertically arranged with gaps 50b between spacers 50 also vertically arranged. As with the left side pump chamber, the spacers 50 in the right side pump chamber 181 can define a spherical, box-like, semi-elliptical depression or any other suitably configured depression. It should be understood, however, that the spacer elements 50 may have a fixed height, a different spatial pattern from those shown, etc.
Also, the membrane 15 may have spacer elements or other features, such as ribs, bumps, ears, grooves, channels, etc., in addition to, or in place of, the spacer elements 50. Such features in the membrane 15 can help prevent adhesion of the membrane 15, etc., and / or providing other features, such as helping to control how the sheets bend or otherwise deform when moved during the pumping action. For example, bulges or other features in membrane 15 can help the sheet to deform consistently and prevent bending in the same area (s) during repeated cycling. Bending of the same area of membrane 15 in repeated cycles can cause membrane 15 to fail prematurely in the area of bending, and therefore the characteristics in membrane 15 can help control the way in which bends occur and in where they occur.
In this illustrative embodiment, base member 18 of cassette 24 defines a plurality of controllable valve features, fluid paths, and other structures to guide fluid movement in cassette 24. Figure 6 shows a plan view of the side of the base member pump chamber 18, also seen in perspective view in Figure 3. Figure 8 shows a perspective view of a rear side of the base member 18 and Figure 9 shows a plan view of the rear side of the base member 18. Tube 156 for each of ports 150, 152 and 154 communicates fluidly with a respective valve well 183 that is formed in the base member 18. Valve wells 183 are fluidly isolated from each other by walls surrounding each valve well 183 and by sealing engagement of the membrane 15 with the walls around the wells 183. As mentioned above, the membrane 15 can sealably engage the walls around each valve well 183 (and other walls of base member 18) as they are pressed into contact with the walls, for example, when they are loaded into cycler 14. Fluid in valve wells 183 can flow to a respective valve port 184, if membrane 15 is not pressed into the sealing engagement with valve port 184. Therefore, each valve port 184 defines a valve ( for example, a volcano valve) that can be opened and closed by selectively moving a portion of the membrane 15 associated with valve port 184. As described in more detail below, cycler 14 can selectively control the position of portions of membrane 15 so that valve ports (such as ports 184) can be opened or closed to control flow through the various fluid channels and other paths in cassette 24. Flow through valve ports 184 leads to the rear side of base member 18. For valve ports 184 associated with the heater bag and drain (ports 150 and 152), valve ports 184 lead to a common channel 200 formed on the rear side of base member 18. Same as with valve wells 183, channel 200 is isolated from other channels and paths of cassette 24 by sheet 16 making sealing contact with the walls of base member 18 that form channel 200. For valve port 184, associated with patient line port 154, flow through port 184 leads to a common channel 202 on the rear side of base member 18.
Returning to Figure 6, each of the pins 160 (shown without a cap in Figure 6) fluidly communicates with a respective valve well 185, which are isolated from each other by walls and membrane sealing hook 15 with the walls forming the wells 185. Fluid in the valve wells 185 can flow to a respective valve port 186, if the membrane 15 is not in sealing engagement with port 186. (Again, the position of portions of the membrane 15 on each valve port 186 can be controlled by cycler 14 to open and close valve ports 186.) Flow through the ports of
<img file="MX2014005451A_D0011.tif" />
valve 186 leads to the rear side of base member 18 and into common channel 202. Therefore, in accordance with one aspect of the invention, a cassette may have a plurality of solution supply lines (or other lines that provide materials for provide dialysate) that are connected to a common manifold or cassette channel, and each line may have a corresponding valve to control flow to / from the line with respect to the common manifold or channel. Fluid in channel 202 can flow to lower openings 187 in pump chambers 181 through openings 188 leading to lower pump valve wells 189 (see Figure 6). Flow from the lower pump valve wells 189 can pass through a respective lower pump valve port 190 if a respective portion of the membrane 15 is not pressed in sealing engagement with port 190. As can be seen in Figure 9, the lower pump valve ports 190 lead to a channel that communicates with the lower openings 187 of the pump chambers 181. Flow from the pump chambers 181 can pass through the upper openings 191 and into a channel that communicates with an upper valve port 192. Flow from upper valve port 192 (if membrane 15 is not in sealing engagement with port 192) can pass into the respective upper valve well 194 and into an opening 193 that communicates with common channel 200 in the back side of base member 18.
As will be appreciated, cassette 24 can be controlled so that pump chambers 181 can pump fluid from and / or into any of ports 150, 152 and 154 and / or any of pins 160. For example, the fresh dialysate provided by one of the containers 20 that is connected by a line 30 to one of the pins 160 can be brought into common channel 202 by opening the appropriate valve port 186 for the appropriate pin 160 (and possibly closing other valve ports 186 for other pins). Also, the bottom pump valve ports 190 can be opened and the top pump valve ports 192 can be closed. Subsequently, the portion of the membrane 15 associated with the pump chambers 181 (i.e., pump membranes 151) can be moved (for example, away from the base member 18 and the inner wall of the pump chamber) to decrease the pressure in pump chambers 181, thus bringing fluid through selected spike 160 through corresponding valve port 186, into common channel 202, through openings 188 and into lower pump valve wells 189, through lower (open) pump valve ports 190, and into pump chambers 181 through lower openings 187. Valve ports 186 are independently operable, allowing the option to carry fluid through any or a combination of pins 160 and associated source containers 20, in any desired sequence, or simultaneously. (Of course, only one pump chamber 181 needs to be operable to carry fluid within it. The other pump chamber can be rendered inoperable and closed for flow by closing the appropriate lower pump valve port 190).
With the fluid in the pump chambers 181, the lower pump valve ports 190 can be closed, and the upper pump valve ports 192 can be opened. When the membrane 15 is moved towards the base member 18, the pressure in the pump chambers 181 can increase, causing the fluid in the pump chambers 181 to pass through the upper openings 191, through the valve ports of upper (open) pumps 192 and into upper pump valve wells 194, through openings 193 and into common channel 200. Fluid in channel 200 can be routed to heater bag port 150 and / or drain port 152 (and to the corresponding heater bag line or drain line) by opening the appropriate valve port 184. In this way, for example, the fluid in one or more of the containers 20 can be brought to the cassette 24, and pumped to the heater bag 22 and / or the drain.
Fluid in heater bag 22 (eg, after having been adequately heated in the heater tray for patient introduction) can be brought to cassette 24 by opening valve port 184 for heater bag port 150 , by closing the lower pump valve ports 190, and opening the upper pump valve ports 192. By moving portions of the membrane 15 associated with the pump chambers 181 away from the base member 18, the pressure in the pump chambers 181 can be reduced, causing fluid to flow from the heater bag 22 and into the chambers. pump 181.
With the pump chambers 181 filled with heated fluid from the heater bag 22, the upper pump valve ports 192 can be closed and the lower pump valve ports 190 can be opened. To direct the heated dialysate to the patient, valve port 184 for patient port 154 can be opened and valve ports 186 for pins 160 can be closed. Movement of the membrane 15 in the pump chambers 181 towards the base member 18 can increase the pressure in the pump chambers 181 causing fluid to flow through the lower pump valve ports 190, through the openings 188 and into common channel 202 to, and through valve port (open) 184 to patient port 154. This operation can be repeated an appropriate number of times to transfer a desired volume of heated dialysate to the patient.
When the patient is drained, valve port 184 for patient port 154 can be opened, upper pump valve ports 192 can be closed, and lower pump valve ports 190 can be opened (with ports spike valve 186 closed). Membrane 15 can be moved to bring fluid from patient port 154 and into pump chambers 181. Subsequently, the lower pump valve ports 190 can be closed, the upper valve ports 192 can be opened, and valve port 184 for drain port 152 can be opened. Fluid from pump chambers 181 can then be pumped into the drain line for disposal or sampling into a drain or collection container. (Alternatively, the fluid may also be directed to one or more dowels 160 / lines 30 for sampling or drainage purposes.) This operation can be repeated until sufficient dialysate is removed from the patient and pumped into the drain.
Heater bag 22 can also serve as a mixing container. Depending on the specific treatment requirements for an individual patient, dialysate or other solutions having different compositions can be connected to cassette 24 via solution lines 30 and suitable pins 160. The measured amounts of each solution can be added to the heater bag 22 using cassette 24, and mixed in accordance with one or more pre-determined formulas stored in microprocessor memory and accessible by control system 16. Alternatively, treatment parameters Specific can be entered by the user through user interface 144. Control system 16 can be programmed to compute appropriate mixing requirements based on the type of dialysate or solution containers attached to pins 160, and can then control mixing and delivery of the prescribed mixture to the patient.
In accordance with one aspect of the invention, the pressure applied by the pumps to the dialysate that is infused into the patient or removed from the patient can be controlled such that the patient's pull or pull sensations resulting from pressure variations during operations Draining and filling can be minimized. For example, when the dialysate is drained, the suction pressure (or vacuum / negative pressure) can be reduced near the end of the drainage process, thus minimizing the patient's sensation of dialysate withdrawal. A similar approach can be used when you are near the end of a filling operation, that is, the supply pressure (or positive pressure) can be reduced near the end of the filling. Different pressure profiles can be used for different fill and / or drain cycles in the event that the patient is found to be more or less sensitive to fluid movement during different cycles of therapy. For example, a relatively higher (or lower) pressure can be used during fill and / or drain cycles when a patient is sleeping, compared to when the patient is awake. Cycler 14 can detect the patient's sleep / wake state, for example, using an infrared motion detector and inferring sleep if the patient's movement is reduced, or using a detected change in blood pressure, brain waves, or other parameter which is indicative of sleep, etc. Alternately, cycler 14 may simply ask the patient - is he sleeping? and control the operation of the system based on the patient's response (or lack of response).
Apparatus for detecting the state of the patient's line
In one aspect, a patient line status detector detects when a fluid line to a patient, such as patient line 34, is suitably initiated with the fluid before connecting to the patient. (It should be understood that although a patient line condition detector is described in relation to a patient line, aspects of the invention include detecting the presence of any suitable tube segment or other conduit and / or a condition of filling of the tube segment or other conduit. Thus, the aspects of the invention are not limited to being used with a patient line, since a tube condition detector can be used with any suitable conduit). In some embodiments, a patient line status detector can be used to detect proper priming of a segment of the tube from the patient connection end of a fluid line. Patient line 34 can be connected to an internal catheter in a patient's blood vessel, in the body cavity, subcutaneously, or in another organ. In one embodiment, patient line 34 may be a component of a peritoneal dialysis system 10, which supplies dialysate to and receives fluid from a patient's peritoneal cavity. A segment of the tube near the distal end of the line can be placed in an upright position on a bracket within which the detector elements of the detector are located. Figure 9-1A shows a front perspective view of an exemplary configuration of a patient line status detector 1000, which can be mounted on or otherwise exposed to the exterior of the left side of housing 82, for example, to the left side of front door 141. Patient line 34 should preferably be started before connecting to the patient, since air could otherwise be supplied to the patient, raising the risk of complications. It may be permissible in some configurations to allow up to 1 ml_ to be present in patient line 34 before connecting to the patient's peritoneal dialysis catheter. The exemplary configurations of the Patient Line Status Detector 1000 described below will generally meet or exceed this standard as they are capable of detecting a liquid level in a properly positioned tube segment of line 34 such that at most appropriately 0.2 mL of air remain at the distal end of line 34 after starting.
In one aspect, a first line patient line condition detector 1000 may include a base member 1002. There may also be a housing for the patient line condition detector 1006 fixed to (or co-molded with) base member 1002 so that detector housing 1006 can extend outwardly from base member 1002. Detector housing 1006 defines a connector holding tube or channel 1012 into which a segment of tube 34a can be placed near the distal end of a patient line 34, or its related connector 36. The housing portion of detector 1006 facing the base member 1002 can be substantially hollow and as a result an open cavity 1008 (shown in Figure 9-3) can be created behind the detector housing 1006. Open cavity 1008 can accommodate the placement and positioning of the detector elements (1026, 1028, 1030, and 1032 shown in Figure 9-3) near channel 1012 into which tube segment 34a can be placed. In an alternative embodiment, there may also be a stabilizer tab 1010 that extends outwardly from base member 1002. The stabilizer tab 1010 may have a concave outer shape, so that it can substantially conform to the curvature of the patient line connector 36 when the patient line 34 is placed in the patient line condition detector housing 1006. The Stabilizing tab 1010 can help prevent connector 36 from moving during initiation of patient line 34, increasing the accuracy and efficiency of the initiation process. Detector housing 1006 may have a shape that generally helps define the connector holding tube or channel 1012, which in turn may have dimensions that vary to accommodate the transition from a tube segment 34a to a tube connector 36. .
In this illustrative embodiment, channel 1012 can substantially conform to the shape of the patient line connector 36. As a result, channel 1012 can be U-shaped to encompass a portion of connector 36 when it is placed in channel 1012. The Channel 1012 can be made of two distinct characteristics; a portion of tube 1014 and a support 1016. In another aspect, the portion of tube 1014 can be positioned underneath support 1016. Additionally, support 1016 may be formed by a pair of side walls 1018 and a back wall 1020. Both side walls 1018 may be slightly convex in shape, while back wall 1020 may be generally flat or otherwise have a matching contour. generally in the shape of the adjacent portion of connector 36. A generally convex shape of the side walls 1018 helps lock the patient line connector 36 in place when positioned on platform 1016.
In an illustrative embodiment for a first configuration of the patient line condition detector 1000, a region 36a of the patient line connector 36 can have a generally flat surface that can rest securely against the opposite rear wall 1020 of the channel 1012. Additionally, this region 36a of connector 36 may have depressions 37 on opposite sides, which can be positioned adjacent to opposite side walls 1018 of channel 1012 when connector 36 is placed within detector housing 1006. The depressions 37 may be defined by raised flanking elements 37a of the connector 36. One of these depressions 37 is partially visible in Figures 9-1A and 9-1B. The two side walls 1018 may have a generally mating shape (such as a convex shape) to engage depressions 37 and to help lock connector 36 in place within platform 1016. This helps prevent the connector 36 and the tube segment 34a is inadvertently removed from the detector housing 1006 during initiation of patient line 34. If the raised members 37a of the connector 36 are made of sufficiently flexible material (such as, for example, polypropylene, polyethylene, or other such polymer-based material) a threshold pulling force against the connector 36 will be able to disengage the connector 36 and the tube segment 34a of the detector housing 1006.
In another aspect, tube portion 1014 of cavity 1012 may surround a greater portion of tube segment 34a at a point just before tube segment 34a is attached to connector 36. Tube portion 1014 may contain greater part of the tube segment 34a using three structures: the two side walls 1018 and the back wall 1020. In one embodiment, the two side walls 1018 and the back wall 1020 may be transparent or sufficiently translucent (constructed of, for example, plexivision) to allow light from a plurality of LEDs (such as, for example, LEDs 1028, 1030 , and 1032 in Figure 9-3) is directed through the walls without blocking or diffusing significantly. An optical detector 1026 (shown in Figure 9-2), can also be positioned along one of the walls 1018, and can detect the light emitted by the LEDs. In the illustrated embodiment, a transparent or translucent plastic insert 1019 can be constructed to snap shut into the main detector housing 1006 in the region where the LEDs have been positioned in the housing.
Figure 9-2 shows a perspective plane view with LEDs 1028, 1030, and 1032 and optical detector 1026 mounted on the surface on a printed circuit board of patient line status detector 1022. Figure 9 -3 shows a plan view of the 1028 LEDs,
1030, and 1032 and the optical detector 1026 mounted on the detector circuit board 1022, wherein the detector circuit board 1022 can be positioned adjacent to the rear wall 1020 and the side walls 1018 of the detector housing 1006. Figure 9-4 is an exploded perspective view of a sensing assembly 1000 showing the relative positions of printed circuit board 1022 and transparent or translucent plastic insert 1019 with respect to housing 1006.
Referring also to the illustrative embodiment of Figure 91B, the detector 1022 circuit board may be placed in a support structure 1004 and within the open cavity 1008, which was formed from the detector housing 1006 extending outward from base member 1002. Base member 1002 and support structure 1004 can be attached to each other, or can be co-molded such that base member 1002 is generally perpendicular to support structure 1004. This orientation generally allows the plane of the board The circuitry of detector 1022 is generally perpendicular to the long axis of tube segment 34a when secured within channel 1012. Detector circuit board 1022 can generally conform to the cross-sectional shape of open cavity 1008, and may also include a cutout 1024 (Figures 9-2, 9-3) that generally matches the channel cross-sectional shape 1012 which is formed by the rear wall 1020 and the side walls 1018 (Figure 9-1 A). The detector circuit board 1022 can then be placed within the open cavity 1008 with the cutout
100
1024 almost adjacent to side walls 1018 and back wall 1020 of detector housing 1006 to ensure proper alignment of detector circuit board 1022 with tube segment 34a or connector 36.
The detector 1022 circuit board can include a plurality of LEDs and at least one optical detector, which can be attached to circuit board 1022, and in one embodiment, the LEDs and optical detector can be surface mounted to circuit board 1022 In one aspect, the detector 1022 circuit board may include a first LED 1028, a second LED 1030, a third LED 1032, and an optical detector 1026. A first LED 1028 and a second LED 1030 can be positioned to direct light through the same side wall 1018a of channel 1012. The light emitted by the first LED 1028 and the second LED 1030 can be directed in a generally parallel direction, generally perpendicular to the side wall 1018a from which they are closest. An optical detector 1026 can be placed along the opposite side wall 1018b of channel 1012. Furthermore, a third LED 1032 can be placed along the rear wall 1020 of channel 1012. In this illustrative embodiment, such configuration of LEDs and optical detector 1026 allows patient line status detector 1000 to detect three different states during the initiation of patient line 34; a tube segment 34a or connector 36 almost completely filled with fluid (started state), an incompletely filled tube segment 34a or connector 36 (not started state), or the
101 absence of a tube segment 34a and / or connector 36 of channel 1012 (state of line absence).
When used in a peritoneal dialysis system, such as the peritoneal dialysis system 10, configuring the circuit board of the detector 1022 in this way allows the appropriate control signal to be sent to the PD 16 cycler controller system. Controller system 16 can then inform the user, via user interface 144, to position the distal end of line 34 on the patient line condition detector 1000 prior to making a connection to the peritoneal dialysis catheter . The controller can then monitor the placement of the tube segment 34a within the patient line status detector 1000. The controller can then proceed to direct the initiation of line 34, to direct the termination of initiation once the line has been initiated, and then instruct the user to disengage the distal end of line 34 from the status detector. from patient line 1000 and connect it to the user's peritoneal dialysis catheter.
The surface mounting the LEDs 1028, 1030, and 1032 and the optical detector 1026 to the circuit board 1022 can simplify the manufacturing procedures for the device, can allow the 1000 patient line status detector and the circuit board 1022 take up a relatively small amount of space, and can help eliminate errors that can arise from movement of the LEDs or the optical detector with each other or channel 1012. If not for surface mounting of
102 components of the detector, misalignment of the components could occur during the assembly of the device or during its use.
In one aspect, the optical axis (or central optical axis) of LED 1032 may form an oblique angle with the optical axis of optical detector 1026. In the illustrated embodiment, the optical axis of a first LED 1028, a second LED 1030, and an optical detector 1026 are each generally parallel to each other and to the rear wall 1020 of channel 1012. Thus, the amount of light directed at the optical detector 1026 from the LEDs can vary depending on the presence or absence of (a) a transparent or translucent conduit within channel 1012 and / or (b) the presence of liquid within the duct (which, for example, may be the tube segment 34a). Preferably, LED 1032 can be positioned close to the side wall (eg, 1018a) which is the furthest from optical detector 1026 so that some of the light emitted by LED 1032 is refracted by the presence of a segment of translucent or transparent tube 34a within channel 1012. The degree of refraction away from or toward optical detector 1026 may depend on the presence or absence of fluid in tube segment 34a.
In various embodiments, the oblique angle of LED 1032 relative to optical detector 1026 creates a firmer system for determining the presence or absence of liquid with a transparent or translucent conduit in channel 1012. LED 1032 can be positioned so that its optical axis can form any angle between 91 ° and 179 ° with respect to the optical axis of optical detector 1026. Preferably the angle can be set within the
103 range from about 95 ° to about 135 ° from the optical axis of the optical detector. More preferably, LED 1032 can be set to have an optical axis of approximately 115 ° +/- 5 ° with respect to the optical axis of optical detector 1026. In an illustrative embodiment shown in Figure 9-3, the angle Θ of the optical axis of the LED 1032 relative to the optical axis of the optical detector 1026 is set to approximately 115 °, +/- 5 °. (The optical axis of the optical detector 1026 in this particular embodiment is approximately parallel to the rear wall 1020, and approximately perpendicular to the side wall 1018b). The advantage of rotating LED 1032 with 10 relative to the optical axis of optical detector 1026 was confirmed in a series of tests comparing the performance of optical detector 1026 to distinguish a segment of the fluid filled tube (wet tube) from a segment of the tube air filled (dry tube) using a 1032 LED that is oriented at approximately an angle of 115 ° vs. an LED whose optical axis is directed either perpendicularly or parallel to the optical axis of the optical detector 1026.
The results showed that an LED-based angled system was more robust in distinguishing the presence or absence of liquid in tube segment 34a. By using an angled LED 1032, it was possible to select an optical detector signal strength threshold above which an empty tube segment 20 34a could be reliably detected. It was also possible to select an optical detector signal strength threshold below which a liquid filled tube segment 34a could be reliably detected.
104
Figure 9-12 shows a graph of test results demonstrating the ability of Patient Line Status Detector 1000 to distinguish between a liquid filled tube segment 34a (started state) and an empty tube segment 34a (non-status). initiated). Results were recorded with LED 1032 (third LED) oriented at an angle of approximately 115 ° to the optical axis of optical detector 1026, and LED 1030 (second LED) oriented approximately parallel to the optical axis of optical detector 1026. The Results plotted in Figure 9-12 demonstrate that Patient Line Status Detector 1000 can safely discriminate between an initiated state and an uninitiated state. When the relative signal strength related to the light received from the LED 1030 was approximately 0.4 or higher, it was possible to resolve an upper signal detection threshold 1027 and a lower signal detection threshold 1029 for an uninitiated state vs. been started using only the light signal received from LED 1032. The upper threshold 1027 can be used to identify the uninitiated state, and the lower threshold 1029 can be used to identify the started state. Data points located above upper threshold 1027 are associated with an empty tube segment 34a (uninitiated state), and data points below lower threshold 1029 are associated with a liquid filled tube segment 34a ( started state). A relatively narrow region 1031 between these two threshold values defines a relative signal strength band associated with light received from LED 1032 at
105 that an evaluation of the initiation state of tube segment 34a may be undetermined. A controller (such as, for example, control system 16) can be programmed to send the user an appropriate message whenever a signal strength related to the light received from the LED 1032 falls within this indeterminate range. For example, the user may be instructed to evaluate whether tube segment 34a and / or connector 36 is properly mounted on patient line status detector 1000. In the context of a peritoneal dialysis system, whether optical detector 1026 generates a signal that corresponds to a segment of empty tube 34a, the controller can direct the cycler to continue initiating patient line 34 with dialysate. A signal corresponding to a liquid filled tube segment 34a can be used by the controller to stop further initiation and instruct the user that fluid line 34 is ready to connect to a dialysis catheter.
In one mode, the cycler controller can continuously monitor the signal received from one of the LEDs at the start of the initiation procedure. Upon detection of a change in the received signal, the controller can stop additional fluid pumping to perform a full measurement using all LEDs. If the received signals are well within the range indicated by a wet tube, then further initiation can be stopped. However, if the received signals are well within the indeterminate region 1031 or within the dry region, then the cycler can command a series of small pulses in
106 Fluid increase in the patient line by means of the pump cassette, with a repeat reading of the LED signal strengths after each fluid pulse. The initiation can then be stopped as soon as a reading is reached that indicates a fluid filled line at the detector level. Increasing fluid pulses can be achieved by ordering short pulses from the valve that connects the pressure reservoir to the pump's drive or control chamber. Alternatively, the controller may command the application of continuous pressure to the pump's drive or control chamber, and command that the pump outlet valve be briefly opened and closed to generate the series of fluid pulses.
Figure 9-13 shows a graph of test results demonstrating the superiority of an angled LED 1032 (LEDc) when compared to an LED (LEDd) whose optical axis is approximately perpendicular to the optical axis of optical detector 1026. In In this case, the relative signal strength generated by the optical detector 1026 in response to the light from the LEDc was plotted against the light related signal strength from the LEDd. Although some separation between a liquid filled (started) and empty (not started) tube segment 34a was apparent at a relative signal strength of LEDd of approximately 0.015, a substantial number of uninitiated 1035 data points remained that did not they can be distinguished from initiated data points based on this threshold value. On the other hand, a relative signal strength 1033 associated with light from the LEDc of 0.028 - 0.03 can effectively discriminate between a tube segment 34a
107 started (started state) and a pipe segment 34a not started (state not started). Thus an angled LED (1032) can generate more reliable data than the orthogonally oriented LED.
In another embodiment, a patient line status detector 1000 can also determine if a tube segment 34a is present in channel 1012. In one aspect, a first LED 1028 and a second LED 1030 can be placed close to each other. An LED (eg, LED 1028) can be positioned such that its optical axis passes approximately through the center of a translucent or transparent conduit or tube segment 34a appropriately positioned in channel 1012. The second LED (eg LED 1030) can be positioned such that its optical axis moves slightly off-center with respect to the conduit or tube segment 34a in channel 1012. Such center-to-center / off-center link has been shown to be LEDs on one side of channel 1012, with an optical detector 1026 on the opposite side of channel 1012, increases reliability in determining whether a liquid conduit or tube segment 34a is present or absent within channel 1012. In a series of tests where a segment of tube 34a was alternately absent, present but inappropriately positioned, or present and appropriately positioned within channel 1012, signal measurements were taken by means of optical detector 1026 from the first and second LEDs. LEDs 1030. The signals received from each LED were plotted against each other and the results are shown in Figure 9-14.
108
As shown in Figure 9-14, in most cases where tube segment 34a was absent from channel 1012 (region 1039), the signal strength received by optical detector 1026 was found to be attributable to LEDa (receiving force of LEDa) was not significantly different from the strength of the signal received from LEDa during the calibration step where the LEDa lit up in the known absence of any tube in channel 1012. Similarly, it was found that the signal strength related to the LEDb (LEDb reception strength), was not significantly different from the LEDb during a calibration step where the LEDb lit up in a known absence of any tube in the channel 1012. The patient line status detector 1000 can reliably determine that no tube is present within channel 1012 if the ratio of the LEDa to its calibration value, and the ratio of the LEDb to its calibration value are approximately 1 + twenty %. In a preferred embodiment, the threshold ratio can be set to 1 + 15%. In an embodiment where the patient line status detector 1000 is used in conjunction with a peritoneal dialysis cycler, the values of LEDa and LEDb within region 1039 of Figure 9-14, for example, can be use to indicate the absence of segment of tube 34a from channel 1012. The cycler controller can be programmed to stop additional pumping actions and inform the user via user interface 144 of the need to properly position the end
109 distal to patient line 34 within patient line condition detector 1000.
The configuration and alignment of the three LEDs and the optical detector 1026 described above are capable of generating the required data using transparent or translucent fluid passages (eg tube segment 34a) having a wide range of translucency. In further testing, the 1000 Patient Line Status Detector was found to be capable of providing reliable data to distinguish liquid from air in a fluid line, or the presence or absence of a fluid line, using samples from the tube with significantly different degrees of translucency. It was also able to provide reliable data regardless of whether the PVC tube was used in a non-sterile or sterile manner (eg EtOx-sterilized). .
The measurements taken by the optical detector 1026 from the LEDs can be used as inputs to a patient line status detector algorithm in order to detect the status of the tube segment 34a. In addition to detecting a complete, empty, or absent tube segment 34a, the result of the algorithm may be indeterminate, possibly indicating improper movement or positioning of tube segment 34a within the patient line status detector 1000, or possibly the presence of a Foreign object on channel 1012 of patient line status detector 1000. Manufacturing variations can cause them to vary between different assemblies, the LED output, and the sensitivity of the
110 optical detector 1026. Therefore, it may be advantageous to perform an initial calibration of the patient line status detector 1000. For example, the following procedure can be used to obtain calibration values from the LEDs and the detector:
(1) Ensure that no segment of tube 34a is loaded into the patient line condition detector 1000.
(2) Probe the 1026 optical detector in four different states:
(a) no LED lit (b) first LED 1028 (LEDa) lit (c) second LED 1030 (LEDb) lit (d) third LED 1032 (LEDc) lit (3) Subtract the signal value of no lit LEDs from each one of the other signal values to determine your environmental corrected values and store these three readings as calibration values for no tubes.
Once the calibration values for the LEDs and the detector are obtained, the status of the tube segment 34a can then be detected. In this illustrative embodiment, the patient line status detector algorithm performs status detection on a test as follows:
(1) Probe the 1026 optical detector in four different states:
(a) no LEDs lit (b) first LED 1028 (LEDsa) lit
111 (c) second LED 1030 (LEDb) illuminated (d) third LED 1032 (LEDc) illuminated (2) Subtract the value of no illuminated LEDs from each of the other values to determine their environmental corrected values.
(3) Calculate relative LED values by dividing the test values associated with each LED by their corresponding calibration values (no tubes).
Results:
-If the ambient corrected LEDa value is less than 0.10, then there may be a foreign object in the detector, or an undetermined result may be reported to the user.
-If the ambient corrected LEDa and LEDb values are within ± 15% of their respective stored calibration values (no tubes), then report to the user that no tube segment is present in the detector.
-If the value of the environmental corrected LEDb is equal to or greater than approximately 40% of its stored calibration value ('no tube'), (a) check the signal associated with the LEDc (i) if the environmental corrected signal related to the LEDc is equal to or greater than approximately 150% of its calibration value ('no tube'), then report to the user that the tube segment is empty.
<img file="MX2014005451A_D0012.tif" />
(ιι) If the environmental corrected signal related to the LEDc is equal to or less than approximately 125% of its calibration value ('no tube'), then report to the user that the tube segment is filled with liquid.
(iii) Otherwise, the result is undetermined, and repeat the measurement (for example, the tube segment may be moving, may be indented or otherwise obscured), or report to the user that the tube segment must be verified to ensure it is properly inserted into the detector.
-If the ambient corrected LEDb value is less than about 40% of its stored calibration value ('no tube'), then the threshold of the LEDc to determine the presence of a dry tube may be higher. In one embodiment, for example, the empty tube threshold of LEDc was found to empirically follow the relationship: [empty tube threshold of LEDc] = -3.75 X [value of LEDb] + 3.
Once it is determined that the tube segment 34a has been loaded into the patient line status detector 1000, the patient line status detector algorithm can do the following:
a) Probe the 1026 optical detector with no LEDs lit and store this as the value of no LEDs.
b) Illuminate the LEDc
c) Probe the optical detector 1026, subtract the value of no LEDs from the value of the LEDc, and store this as the initial value.
113
d) Start pumping
e) Probe optical detector 1026 and subtract the value of no LEDs from the subsequent value of the LEDc.
f) If this value is less than 75% of the initial value, then conclude that the tube segment 34a is filled with liquid, stop pumping, confirm the status of the detector using the previous procedure, and when indicated, report to the user that the initiation is complete. Otherwise, keep repeating the poll, calculation, and comparison. In one mode, the system controller can be programmed to perform the polling protocol as often as desired, such as every 0.005 to 0.01 seconds. In one embodiment, the entire poll cycle can be conveniently performed every 0.5 seconds.
Figure 9-12A shows the results of the sample calibration procedures for six cyclists. Note that the signal strength range that distinguishes a dry tube from a wet tube (wet / dry threshold ranges) varies between different cyclists. (Variations in these ranges may be due to minor variations in manufacturing, assembly, and positioning of individual components.) Thus, in calibration, each cycler can be assigned a wet / dry threshold signal strength interval that optimally separates data points generated with a dry tube from data generated with a wet tube.
Figure 9-5 shows a perspective view of a second configuration of a patient line status detector 1000. Two or
114 further different configurations of the patient line status detector may be necessary to accommodate various types of patient connectors. In this illustrative embodiment, the patient line status detector of the second configuration 1000 can include most of the same components as in the patient line status detector of the first configuration 1000. However, to accommodate a different type of connector, the second configuration may include a raised element 1036 above housing 1006, in place of stabilizer tab 1010 found in the patient line status detector of first configuration 1000. Raised element 1036 can generally conform to the shape of a standard patient line connector cap or connector flange.
In accordance with one aspect of the description, the housing of the detector 1006 may not include a portion of the tube 1014. Therefore, an open cavity 1008 may be arranged to allow placement of a circuit board of the detector 1022 such that the LEDs and the optical detector can be placed near a transparent or translucent patient line connector 36 instead of a section of the tube. Accordingly, channel 1012 may be formed differently to accommodate transmission of the LED light through connector 36.
<img file="MX2014005451A_D0013.tif" />
Organizer of the Solution Line
Figure 9-6, Figure 9-7, and Figure 9-8 show a perspective view of the front of an unloaded organizer 1038, a perspective view of the rear of an unloaded organizer 1038, and a perspective view of a loaded organizer 1038 respectively. In this embodiment, organizer 1038 can be formed substantially of a moderately flexible material (such as, for example, PAXON AL55003 HDPE resin). Forming the 1038 organizer from this or another relatively flexible polymer material increases the durability of the 1038 organizer when attaching and removing solution lines or solution line connectors.
The organizer 1038 can be conveniently mounted or attached to an exterior wall of the cycler housing 82. The organizer 1038 can include a tube support section 1040, a base 1042, and a tab 1044. The tube support section 1040, the base 1042, and tab 1044 can all be flexibly connected, and can be formed of substantially the same HDPE-based material. The tube support section 1040 may have a generally rectangular shape, and may include a generally flat top edge and a bottom edge that can be slightly curved in an outward direction. The tube support section 1040 may include a series of depression segments 1046 that extend horizontally along the bottom edge of the tube support section 1040. Each of the depression segments 1046 can be separated by a series of columns of
116 bracket 1048, which can also define the shape and size of segments 1046. The tube bracket section 1040 can also include a raised area that extends horizontally along the top edge of the tube bracket section 1040. The raised area may include a plurality of grooves 1050. Grooves 1050 can be defined in a vertical orientation, and can extend from the top edge of tube support section 1040 to the top of depression segments 1046. Grooves 1050 can be generally cylindrical in shape to conform to the shape of a drain line 28, solution line 30, or patient line 34. The depth of the grooves 1050 may be such that the opening of the groove 1050 is narrower than the interior region of the groove 1050. Therefore, once a line is placed in the groove 1050 it locks or snaps closed instead. The line may then require a predetermined minimum amount of force to be removed from the slot 1050. This ensures that the lines are not inadvertently removed from the 1050 organizer.
In one aspect, tab 1044 can be flexibly connected to the top edge of tube support section 1040. Tab 1044 can be generally rectangular in shape. In another embodiment, tab 1044 can also include two corners with slightly larger radius 80. Tab 1044 can also include two vertically extending support columns 1048. The support columns 1048 can be connected to the upper edge of the tube support section 1040, and
117 they may extend in an upward direction on tongue 1044. In an alternative embodiment, the length and number of support columns 1048 may vary depending on the desired degree of flexibility of tongue 1044. In another aspect, tongue 1044 may include a ribbed area 1052. The purpose of tab 1044 and grooved area 1052 is to allow organizer 1038 to be easily grasped by a user so that user can easily install, transport, or remove solution lines 30 from organizer 1038. Also, tab 1044 Provides an additional area of support when removing and loading lines on the 1038 Organizer.
In another aspect, base 1042 can be flexibly connected to the bottom edge of tube support section 1040. Base 1042 can be generally rectangular in shape. In another embodiment, base 1042 can also include two corners with slightly larger radius 80. Base 1042 can include an elongated depression segment 1046, which can be defined by a support ring 1054 that surrounds depression segment 1046. The support columns 1050, the support ring 1054, and the raised area can all create a series of recesses 1056 along the rear of the organizer 1038 (shown for example in Figure 9-7).
Figure 9-9 and Figure 9-10 show a perspective view of an organizer clip 1058, and a perspective view of an organizer clip receiver 1060 respectively. In these modalities
118 Illustrative, brooch 1058 can be made from a relatively high polyurethane elastomer durometer, such as, for example, a Shore A 80 urethane durometer. In an alternative embodiment, brooch 1058 can be made from any type of flexible and durable material which may allow the organizer 1038 to flex and pivot along the base 1042 when placed on the clasp 1058. Clasp 1058 may be U-shaped and may include a rear portion that extends slightly higher than the front portion. Additionally, there may be a flange 1062 that extends along the top edge of the front portion of clasp 1058. Flange 1062 extends slightly into the cavity of clasp 1058. The rear portion of the clasp 1058 may also include a plurality of elastomeric pins 1064 connected to (or formed from) and extending away from the rear portion of the clip 1058. The pins 1064 can include both a cylindrical section 1066 and a cone 1068. Cylindrical section 1066 can be connected to the rear portion of clasp 1058, and cone 1068 can be attached to an open end of cylindrical section 1066. Pins 1064 allow clip 1058 to be permanently connected to organizer clip receiver 1060, by hooking pins 1064 into a plurality of holes 1070 in organizer clip receiver 1060.
The organizer clip receiver 1060 may include a plurality of beveled tabs 1072. The beveled tabs 1072 may engage corresponding grooves in the rear portion of the
119 snap 1058 when the 1064 pegs engage the 1060 organizer snap receiver. Once the 1072 bevel tabs engage the slots, they can extend through the rear portion of the 1058 snap and act as locking mechanisms to hold the organizer 1038 in place when attached to clasp 1058. When the organizer 1038 is placed inside the clasp 1058, the bezels 1072 fit into the gap 1056 at the back of the base 1042, which was created by the raised support ring 1054. Referring again to Figure 9-7, and in accordance with another aspect of the present disclosure, there may be a plurality of ramps 1074 extending outward from the rear of the organizer 1038. The ramps 1074 can generally be formed as inclined planes. This allows the organizer 1038 to form at an angle away from the cycler 14 when placed on the clip 1058, which provides numerous advantages over previous designs. For example, in this illustrative embodiment, the angle of the organizer 1038 ensures that neither the tab 1044 nor the lines (or line caps) connected to the organizer 1038 interfere with the heater cap 143 when the cap 143 is opened or closed. Additionally, the angle of organizer 1038 relative to cycler 14, coupled with the flexibility of organizer 1038, encourages the user to remove solution lines 30 from the bottom rather than from the end of connector 30a of solution lines. . Preferably, the user should not remove the solution lines 30 by grasping the ends of the connector 30a, because in doing so the user could inadvertently remove one or
120 more lids 31, which could cause contamination and spills. Another advantage of the 1038 organizer is that it helps the user connect the color-coded solution lines 30 to the correct containers 20 by helping to separate the color-coded lines 30.
Door Latch Detector
Figure 9-11 shows a perspective view of a door latch detector assembly 1076. In this illustrative embodiment, the door latch detector assembly 1076 may include a magnet 1078 that is attached to or connected to the 1080 door latch and can be pivoted with the 1080 door latch as it pivots in and out of the latched position with its 1082 docking base unit latch. A detector (not shown in Figure 9-11) can be placed behind the front panel 1084 of cycler 14, near the latch on base unit 1082, to detect the presence of a 1078 magnet as the door latch 1080 engages with the sear of the base unit 1082. In one embodiment, the detector may be an analog Hall effect detector. The purpose of the 1076 door latch detector assembly is to confirm that door 141 closes and that door latch 1080 engages enough with latch 1082 to ensure a structurally sound connection. Figure 9-11a shows a cross-sectional view of the door latch detector assembly 1076. Detector 1079 is positioned on a circuit board 1077 behind the panel
121 1084. Detector 1079 is preferably oriented off-center from the line of motion of magnet 1078, because in this orientation detector 1079 is able to better resolve a variety of positions of magnet 1078 as it approaches front panel 1084 at as door 141 closes.
In one example, door 141 can be considered to be sufficiently engaged when door latch 1080 has at least 50% engagement with latch 1082. In one embodiment, door latch 1080 may latch onto a degree of about 0.30 cm nominally. Additionally, detector 1079 can only detect a closed door 141 when door latch 1080 engages sufficiently with latch 1082. Therefore, detector 1082 can only detect a closed door 141 when door latch 1080 engages to a degree of approximately 0.15 cm. These 1080 door latch engagement thresholds can be set at approximately the median range for acceptable engagement between the 1080 door latch and the 1082 sear. This can help ensure a firm design by taking into account the tilt of the detector due to weather, temperature, and other variations.
The test was performed to determine the firmness of the 1082 detector by collecting numerous measurements both at room temperature (approximately 24 ° C) and at an abnormally cold temperature (approximately -2 ° C to 9 ° C). Ambient temperature readings
122 they were repeatedly higher than the cold readings, but only by a small percentage of the range from 0 cm to 0.015 cm.
In one aspect, the output of detector 1079 may be radiometric to the supplied voltage. Therefore, the supply voltage and the output of detector 1079 can be measured (see formulas below, where the supply voltage and the output of detector 1079 are represented by Gate_Latch and Monitor_5V0 respectively). Both the detector 1079 output and the supplied voltage can then pass through% of the resistor separators. Dividing the output of detector 1079 and the supplied voltage can allow a stable output to occur. This procedure can ensure that the output remains stable even if the supply voltage fluctuates.
In another aspect, detector 1079 can respond to both positive and negative magnetic fields. Therefore, if there is no magnetic field, detector 1079 can produce half the supply voltage. Additionally, a positive magnetic field can cause the output of detector 1079 to increase, while a negative magnetic field can result in a decrease in the output of detector 1079. To obtain an accurate measurement of the output from the 1079 detector, the magnet polarity can be ignored, and the supply voltage can be simultaneously compensated. The following formula can be used to calculate the ratio of the latch detector:
123
Latch detector ratio = absolute value ((VPuerta_Pestillo / VMonitor_5V0) - without Field Ratio) (D
Where the no Field Relationship is calculated as (VPuertaPestillo / VMonitor_5V0) with door 41 fully open.
Using this formula:
Ratio = 0.0 indicates no magnetic field
Ratio> 0.0 indicates some magnetic field; undetermined address.
Wedges of various thicknesses can be used between the interior of door 141 and front panel 1084 to vary the degree of engagement between latch 1080 and latch 1082, to calibrate the strength of the magnetic field detected by detector 1079 with various positions of door latch assembly latch 1076. In one embodiment, this data can be used to develop field strength ratios with and without a wedge, or in other modalities with multiple wedges of various thicknesses. In one example, the 1076 door latch detector assembly can complete the procedure to determine if the 1080 door latch engages sufficiently with the latch 1082 by doing the following:
Calculate the Close Ratio and the Far Ratio:
Close ratio = no Wedge Ratio - (.025 / .060) x (without
Wedge Ratio - with Wedge Ratio) (2)
124
Distant Ratio = no Wedge Ratio - (.035 / .060) x (no Wedge Ratio - with Wedge Ratio) (3)
In one mode, the 1076 door latch detector assembly can save the No Field Ratio, Close Ratio, and Far Ratio in a calibration file. The 1076 door latch detector assembly can then load the No Field Ratio, Close Ratio, and Far Ratio from the calibration file, and the 1076 detector assembly can then use the Close Ratio and Far Ratio as the hysteresis limits detector 1079. The door latch detector assembly 1076 can then start with the initial condition that door 141 is open, and then repeatedly calculate the Latch detector Ratio. If the Latch detector Ratio is greater than the Close Ratio, the door latch detector assembly 1076 will change the state of the latch to closed and if the Latch detector Ratio is less than the Far Ratio, the detector assembly Door latch 1076 will change the state of the latch to open. In an alternative embodiment for assembling the 1076 door latch detector, an Average Ratio can be calculated from the calibration data by averaging the Non-Wedge Ratio and the Wedge Ratio. In this case, measurements greater than the Average Ratio indicate that the 1080 door latch engages, and measurements less than the Average Ratio indicate that the 1080 door latch does not engage.
125
Set Loading and Operation
Figure 10 is a perspective view of the APD system 10 of Figure 1 with door 141 of cycler 14 reduced to an open position, exposing a mounting location 145 for cassette 24 and a cart 146 for solution lines 30. (In this embodiment, door 141 is hinge mounted on a lower portion of door 141 to cycler housing 82.) When assembly 12 is loaded, cassette 24 is placed in mounting location 145 with membrane 15 and the pump chamber cassette 24 side facing upward, allowing portions of the membrane 15 associated with the pump chambers and valve ports to interact with a control surface 148 of the cycler 14 when the door 141 is closed. . Mounting location 145 may be configured to match the shape of base member 18, thereby ensuring proper orientation of cassette 24 at mounting location 145. In this illustrative embodiment, cassette 24 and mounting location 145 have a shape generally rectangular with a single corner of larger radius requiring the user to place cassette 24 in an appropriate orientation at mounting location 145 or door 141 will not close. It should be understood, however, that other shapes or orientation features for cassette 24 and / or mounting location 145 are possible.
In accordance with one aspect of the invention, when cassette 24 is placed at mounting location 145, the patient, drain and heater bag lines 34, 28 and 26 are routed through a channel
126 at door 141 on the left as shown in Figure 10. Channel 40, which may include guides 41 or other features, may contain patient lines, drain, and heater bag 34, 28, and 26 so that an occluder 147 can selectively close / open lines for flow. By closing the door 141, the occluder 147 can compress one or more of the patient lines, drain and heater bag 34, 28 and 26 against the stopper of the occluder 29. Generally, occluder 147 can allow flow through lines 34, 28, and 26 when cycler 14 is operating (and operating properly), but occlude lines when cycler 14 is down-powered (and / or not operating properly). (Occlusion of the lines can be performed by pressing the lines, or in another way by squeezing the lines to close the flow path in the lines.) Preferably, occluder 147 can selectively occlude at least the patient and drain lines. 34 and 28.
When cassette 24 is mounted and door 141 is closed, the cassette side of pump chamber 24 and membrane 15 may be pressed into contact with control surface 148, for example, by an air bladder, spring or another suitable arrangement in door 141 behind mounting location 145 that crushes cassette 24 between mounting location 145 and control surface 148. This containment of cassette 24 can press membranes 15 and 16 into contact with walls and other features of base member 18, thus isolating channels and other flow paths from cassette 24 as desired. Control surface 148 can
127 include a flexible packaging or membrane, for example, a silicone rubber sheet or other material, that is associated with the membrane 15 and can selectively move portions of the membrane 15 to cause the pumping action in the pump chambers 181 and the open / close cassette valve ports 24. Control surface 148 may be associated with the various portions of membrane 15, for example, placed in intimate contact with one another, such that portions of membrane 15 move in response to movement of corresponding portions of the surface of control 148. For example, the membrane 15 and the control surface 148 may be located close to each other, and a suitable vacuum (or pressure that is lower relative to the environment) can be introduced through vacuum ports suitably located on the surface of the control 148, and held between membrane 15 and control surface 148 so that membrane 15 and control surface 148 are essentially glued, at least in regions of the membrane 15 that require movement to open / close valve ports and / or to cause pumping action. In another embodiment, the membrane 15 and the control surface 148 can be adhered to each other, or otherwise suitably be associated.
In some embodiments, the surface of the control surface 148 or gasket facing the corresponding cassette membrane overlying the pump chambers and / or valves is textured or rough. Texturing creates a plurality of small horizontal passages or
128 tangentially along the surface of the packing when the packing is pushed against the surface of the corresponding cassette membrane. This can improve air evacuation between the packing surface and the cassette membrane surface at the textured locations. You can also improve the precision of pump chamber volume determinations using pressure-volume relationships (as, for example, in the FMS procedures described elsewhere in the document), minimizing air pockets trapped between the packing and the membrane. It can also improve the detection of any liquid that might leak in the potential space between the gasket and the cassette membrane. In one embodiment, texturing can be accomplished by masking the portions of the packing mold that do not form the portions of the packing that correspond to the pump membrane and valve membrane locations. A chemical etching process such as the Mold-Tech® chemical etching and texturing process can then be applied to the unmasked portions of the packaging mold. Texturing can also be accomplished by any of many other processes, such as sandblasting, laser engraving, or using a mold manufacturing process using electric discharge machining.
Before closing door 141 with cassette 24 loaded, one or more solution lines 30 can be loaded onto carriage 146. The end of each solution line 30 may include a cap 31 and region 33 for labeling or attaching a indicator or identifier. The indicator, for example,
129 it may be an identification tag which is attached by jumping onto the tube in the region of indicator 33. In accordance with one aspect of the invention and as will be discussed in more detail below, carriage 146 and other components of cycler 14 can be operated to remove cap (s) 31 from lines 30, recognize the indicator for each line 30 (which can provide an indication for the type of solution associated with the line, an amount of solution, etc.) and fluidly hook lines 30 with a respective pin 160 of cassette 24. This process can be done in an automated manner, for example, after door 141 is closed and covers 31 and dowels 160 are enclosed in a protected space from human contact, potentially reducing the risk of contamination of lines 30 and / or or pins 160 when the two are connected together. For example, by closing the door 141, the regions of the indicator 33 can be evaluated (for example, visually by a suitable imaging device and software-based image recognition, by RFID techniques, etc.) to identify which solutions are associated with which lines 30. This aspect of the invention relating to the ability to detect characteristics of a line 30 by means of an indicator in the region of indicator 33 can provide benefits such as allowing a user to place lines 30 at any location on carriage 146 without having an effect. about the operation of the system. That is, since cycler 14 can automatically detect solution line characteristics, there is no need to ensure that specific lines are placed in
130 particular locations on carriage 146 for the system to function properly. Instead, cycler 14 can identify which lines 30 are where, and control cassette 24 and other system features appropriately. For example, a line 30 and connected container may be designed to receive used dialysate, for example, for subsequent testing. Since cycler 14 can identify the presence of sample supply line 30, cycler 14 can direct used dialysate to the appropriate spike 160 and line 30. As described above, since pins 160 of cassette 24 all feed into a common channel, the input of any particular pin 160 can be directed into cassette 24 in any desired manner by controlling the valves and other features of the cassette.
With lines 30 mounted, carriage 146 can be moved to the left as shown in Figure 10 (again, while door 141 is closed), by placing caps 31 over a respective tang cap 63 on a tang 160 from the cassette 24 and adjacent to a cap separator 149. The cap separator 149 can extend outward (toward door 141 from inside a depression in cycler housing 14) to engage caps 31. (For example, the cap separator 149 may include five fork-shaped elements that engage with a corresponding slot in the caps 31, leaving the cap separator 149 to resist the left / right movement of the cap 31 relative to the cap separator 149.) By hooking the caps 31 with the cap separator 149, the caps 31 can also hold the dowel cap
131 63. Subsequently, with the lids 31 hooked with corresponding lug caps 63, the carriage 146 and liner spacer 149 can be moved to the right, removing the lug caps 63 from the lugs 160 which are engaged with a corresponding lid 31. (A possible advantage of this arrangement is that the spigot caps 63 are not removed in locations where no solution line 30 is loaded because latching the cap 31 of a solution line 30 is required to remove a cap from spike 63. Therefore, if a solution line will not be connected to a pin 160, the cap on pin 160 is left in place.) Cap separator 149 can then stop movement to the right (for example, by making contact with a stop), while carriage 146 continues the movement to the right. As a result, carriage 146 can pull the terminal ends of lines 30 of covers 31, which remain attached to cover spacer 149. With the caps 31 removed from the lines 30 (and the stud caps 63 still attached to the caps 31), the cap separator 149 can again retract with the caps 31 toward the depression in the cycler housing 14, clearing a path for movement of carriage 146 and the uncapped ends of lines 30 toward pins 160. Carriage 146 then moves counterclockwise again, fixing the terminal ends of lines 30 with a respective dowel 160 of cassette 24. This connection can be made by dowels 160 by drilling an otherwise closed end of lines 30 (by For example, the dowels can pierce a septum or closed wall in the
132 terminal end), allowing fluid flow from respective containers 20 to cassette 24. In one embodiment, the wall or septum can be constructed of a flexible and / or self-sealing material such as, for example, PVC, polypropylene, or rubber of sillcona.
In accordance with one aspect of the invention, the heater bag 22 can be placed in the receiving section of the heater bag (eg, a tray) 142, which is exposed by lifting a lid 143. (In this embodiment, the Cycler 14 includes a user or operator interface 144 that is pivotally mounted to housing 82, as described below. To allow heater bag 22 to be placed on tray 142, interface 144 can be pivoted up from tray 142. As known in the art, heater tray 142 can heat dialysate in bag heater 22 at a suitable temperature, eg, an appropriate temperature for introduction into the patient. In accordance with one aspect of the invention, lid 143 can be closed after placing heater bag 22 on tray 142, for example, to help trap heat to speed up the heating process, and / or help prevent touch u other contact with a relatively hot portion of the heater tray 142, such as its heating surfaces. In one embodiment, the lid 143 may be locked in a closed position to prevent touching the heated portions of the tray 142, for example, in the circumstance that the portions of the tray 142 are heated to temperatures that can cause skin burn. . The
133 Opening of the lid 143 can be prevented, for example, by a lock, until the temperatures below the lid 143 are suitably low.
In accordance with another aspect of the invention, cycler 14 includes a user or operator interface 144 that is pivotally mounted to cycler housing 14 and can be folded into heater tray 142. With interface 144 folded, cover 143 It can be closed to cancel interface 144 and / or prevent contact with interface 144. Interface 144 may be arranged to display information, eg, in graphical form, to a user, and receive input from the user, eg, using a touch screen and graphical user interface. Interface 144 may include other input devices such as buttons, markers, knobs, pointing devices, etc. With assembly 12 connected and containers 20 properly positioned, the user can interact with interface 144 and cause cycler 14 to initiate treatment and / or perform other functions.
However, before starting a cycle of dialysis treatment, cycler 14 must at least start cassette 24, patient line 34, warmer bag 22, etc., unless assembly 12 is provided in a condition pre-started (for example, in the manufacturing facility or otherwise before being put into use with cycler 14). Initiation can be performed in a variety of ways, such as by controlling cassette 24 (namely pumps and valves) to carry liquid from one or more solution containers 20 via line 30 and pump the liquid through the
134 various paths of cassette 24 to remove air from cassette 24. Dialysate may be pumped into warmer bag 22, for example, for heating prior to delivery to the patient. Once cassette 24 and heater bag line 26 are started, cycler 14 can immediately start patient line 34. In one embodiment, patient line 34 can be initiated by connecting line 34 (eg, via connector 36) to a suitable port or other connection point on cycler 14 and causing cassette 24 to pump liquid into the line from patient 34. The port or connection point on the cycler 14 can be arranged to detect the arrival of liquid at the end of the patient line (for example, optically, by conductive detector, or other), therefore detecting that the patient line is started. As described above, different types of sets 12 may have patient lines 34 of different size, eg, adult or pediatric size. In accordance with one aspect of the invention, cycler 14 can detect cassette type 24 (or at least patient line type 34) and control cycler 14 and cassette 24 accordingly. For example, cycler 14 can determine a volume of liquid delivered by a pump in the cassette, necessary to start patient line 34, and based on volume, determine the size of patient line 34. Other techniques can be used, such as recognizing a barcode or other indicator on cassette 24, patient line 34, or another component that indicates the type of the patient line.
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Figure 11 shows a perspective view of the interior side of door 141 disconnected from housing 82 of cycler 14. This view shows more clearly how lines 30 are received in corresponding slots in door 141 and carriage 146 such that the indicator region 33 is captured in a specific slot of carriage 146. With the indicator in the indicator region 33 appropriately located when the tube is mounted to the cart 146, a reader or other device can identify indications of the indicator, for example, representing a type of solution in container 20 connected to line 30, a quantity of solution, a manufacturing date, a manufacturer identity, etc. Carriage 146 is mounted on a pair of guides 130 at the upper and lower ends of carriage 146 (only the lower guide 130 is shown in Figure 11). Therefore, carriage 146 can be moved from left to right on door 141 along guides 130. When moved to cassette 145 mounting location (clockwise in Figure 11), carriage 146 it can be moved until it makes contact with the stops 131.
Figure 11-1 and Figure 11-2 show a perspective view of carriage 146, and an elongated perspective view of a solution line 30 loaded on the carriage. In these illustrative embodiments, carriage 20 146 may have the ability to move door 141 along guide 130. Carriage 146 may include five slots 1086, and therefore may have the ability to support up to five lines of solution 30. Each 1086 slot can include three different sections; a solution line section
136
1088, an ID section 1090, and a clasp 1092. The solution line section 1088 may have a generally cylindrical-shaped cavity that allows the solution lines 30 to remain organized and unraveled when loaded onto carriage 146. Snap 1092 can be located at the opposite end of each of the 1086 slots, relative to the section of the 1088 solution line. The purpose of clasp 1092 is to provide a secure housing for a membrane port 1094 to be placed at the connector end 30a of solution line 30, and to prevent solution line 30 from moving during treatment.
In one embodiment of the present disclosure, the clasp 1092 may be semicircular in shape, and may include a mid region that extends slightly deeper than the two surrounding edge regions. The purpose of including the deeper mid region is to accommodate a flange of membrane port 1096. Flange 1096 can have a radius substantially greater than the rest of the membrane port. Therefore, the deepest mid region is designed to fit the widest flange 1096, while the two edge regions provide support for membrane port 1094 to be immobilized. Additionally, the deep mid region can have two cutouts 1098 placed on opposite sides of the semicircle. The cutouts 1098 may be generally rectangular in shape to allow a small portion of the flange 1096 to extend into each of the cutouts 1098 when placed in the snap 1092. Cutouts 1098 can be formed so that the
137 The distance between the top edges of each cutout 1098 is slightly less than the radius of the tab 1096. Therefore, a sufficient amount of force is required to attach the tab 1096 to the clasp 1092. Also, allowing the distance between the edges The top of the two cutouts 1098 being less than the radius of the flange 1096 helps prevent the solution line 30 from inadvertently shifting during treatment.
In this illustrative embodiment, carriage 146 can provide superior performance over previous designs due to its ability to counteract any deformation of membrane ports 1094. Carriage 146 is designed to stretch membrane ports 1094 between the front of the flange. 1096 and the back of the sleeve. If the membrane port 1094 is stretched further at any point during treatment, a wall in the carriage 146 can support the flange 1096.
In accordance with another aspect of the present description, the ID 1090 section can be placed between the solution line 1088 section and the snap 1092. The ID 1090 section can be generally rectangular in shape, thus having the ability to store a Identification tag 1100 that can be attached at solution line 30 in the region of indicator 33. Indicator region 33 may have an annular shape that is dimensioned and configured to fit within ID section 1090 when mounted on carriage 146. Identification tag 1100 can provide an indication as to the type of solution associated with each line 30, the amount of solution, a date of
138 manufacturing, and a manufacturer identity. As shown in Figure 111, the ID 1090 section can include a two-dimensional (2-D) barcode 1102, which can be printed on the bottom of the ID 1090 section. The 1102 barcode can be a symbol Data Matrix with 10 blocks per side, and can include an empty Data Matrix code. Bar code 1102 can be placed on carriage 146 under identification tag 1100, when solution lines 30 are loaded on carriage 146. However, in an alternative embodiment, barcode 1102 can be added to the ID 1090 section of carriage 146 by means of a sticker or laser engraving. Also, in another embodiment, barcode 1102 may include a Data Matrix consisting of varying length and width dimensions, as well as varying numbers of blocks per side.
In this illustrative embodiment, however, the specific block number per side, and the specific length and width of each barcode 1102 were specifically chosen to provide the strongest design under a variety of conditions. Using only 10 blocks per side can result in the 1102 barcode having larger blocks, thereby ensuring that the 1102 barcode is easily readable, even under dark conditions that exist within the cycler housing 82.
Figure 11-3 and Figure 11-4 show a perspective view of a folded ID tag 1100 and a top view.
139 perspective of a carriage driver assembly 132 including an AutoID 1104 camera mounted on an AutoID 1106 camera board respectively. In accordance with one aspect of the present disclosure, the ID tag 1100 can be formed from an injection mold and can then be folded to bind around the indicator region 33. Identification tag 1100 may include edges that are rounded, which can prevent solution 20 containers from being damaged during shipping. The 1100 ID tag can also include an 8x8mm 1103 two-dimensional (2-D) Data Matrix symbol with 18 blocks per side plus a print free zone that can be added by means of a sticker. The information contained in these Data Matrix symbols 1103 can be provided from camera 1104 to control system 16, which can then obtain clues, through various processes such as by image analysis. Therefore, the AutoID 1104 camera will have the ability to detect slots 1086 that contain a solution line 30 that is installed correctly, a line 30 that is installed incorrectly, or the absence of a line 30. A correctly installed solution line 30 will allow camera 1104 to detect the Data Matrix symbol 1103 located on identification tag 1100, the absence of a solution line 30 will allow camera 1104 to detect an empty barcode of Data Matrix 1102 located on carriage 146 below membrane port 1094, and a solution line 30 that is incorrectly loaded will occlude the empty Matrix bar code.
140
Data 1102, resulting in no Data Matrix being encoded by camera 1104 for that slot. Thus, camera 1104 should always encode a Data Matrix in each slot 1086 on carriage 146, exposing an incorrectly loaded solution line 30.
In this illustrative embodiment, the ability to detect features of a solution line 30 by means of an identification tag 1100 located in the region of indicator 33 can provide benefits such as letting a user place lines 30 at any location on cart 146 without having an effect on the operation of the system. Additionally, since cycler 14 can automatically detect the characteristics of the solution line, there is no need to ensure that specific lines 30 are placed at particular locations on carriage 146 for the system to function properly. Instead, cycler 14 can identify which lines 30 are where, and control cassette 24 and other system features appropriately.
In accordance with another aspect of the description, identification tag 1100 must be oriented on carriage driver assembly 132 to be decoded by chamber 1104. To ensure this, carriage 146 and identification tag 1100 may have complementary features of alignment. Additionally, solution lines 30 with 1100 ID tags must also fit inside the Cleanflash machine, so solution line 30 with 1100 ID tag can be built to fit inside a cylinder
141 with a diameter of 1.34 cm. In one embodiment, the alignment feature may be a simple flat bottom effect on identification tag 1100 and matching rib on carriage 146. In one embodiment of the present disclosure, the effect and rib may slightly interfere, forcing the back of the 1100 ID tag in an upward direction. Although this setting can create a small amount of mismatch, it reduces the mismatch on the other axis. Lastly, to ensure that the ID tag 1100 is properly seated, the front of the carriage driver assembly 132 can be designed with only about 0.05 cm of clearance over the present carriage 146 and the alignment of the ID tag 1100.
In accordance with another aspect of the description, the AutoID 1106 camera board can be mounted to the rear of the car drive assembly 132. Additionally, the AutoID 1104 camera can be mounted to the 1106 camera board. The camera board 1106 can be placed approximately 10.64 cm from the 1100 identification tag. However, in an alternative mode, the camera board 1106 can be moved backwards without any serious consequence. A plastic window 1108 can also be attached to the front of carriage driver assembly 132, which can allow ID tags 1100 to be imaged while also preventing fluid and finger ingress. The AutoID 1104 camera can include a camera lens, which can be any type of lens, such as those used for
142 security applications, or lenses intended for camera phones with the IR filter removed. According to one aspect of the present description, the camera lens can be small in size, light in weight, low in cost, and of high image quality.
Additionally, a single SMD IR 1110 LED can be attached to the dash of camera 1106. LED 1110 can then illuminate ID tags 1100 so that camera 1104 can easily decode the Data Matrices. It is important that the ID tags 1100 are illuminated because the environment within the cycler housing 82 is mostly lightless. Therefore, without LED 1110 to illuminate ID tags 1100, camera 1104 may be unable to decode the Data Matrices. Also, to avoid creating glare in front of the 1100 ID tags, the 1110 LED can be mounted 1.79 cm from the 1104 camera. An FPGA can also be mounted on the 1106 camera board, and can act as an intermediary between the OV3640 image detector and Voyager's Ul processor. In addition to making the processor's work easier, this architecture can allow a different image detector to be used without any changes to other Voyager hardware or software. Finally, decoding the image is handled by the open source package libdmtx, which is addressable from many programming languages and can be run from a command line for testing.
143
Figure 12 shows a perspective view of a carriage impeller assembly 132 in a first embodiment that operates to move carriage 146 to remove caps from pins 160 in the cassette, remove caps 31 on solution lines 30, and connect lines 30 to pins 160. A driver 133 is arranged to move from left to right along rods 134. In this illustrative embodiment, an air bladder powers the movement of the drive member 133 along the rods 134, but any suitable drive mechanism can be used, including motors, hydraulics, etc. The drive element 133 has forward-extending tabs 135 that engage the corresponding grooves 146a on the carriage 146 (see Figure 11, which shows an upper groove 146a on the carriage 146). Engaging the tabs 135 with the grooves 146a allows the drive member 133 to move the carriage 146 along the guides 130. The drive member 133 also includes a window 136, through which an imaging device, such as a CCD or CMOS imager, it can capture image information from indicators in indicator regions 33 on lines 30 mounted to carriage 146. The image information regarding the indicators in the indicator regions 33 can be provided from the image forming device to the control system 16, which can obtain cues, for example, by image analysis. The drive member 133 can selectively move the cap separator 149 both left and right along the rods 134. The cap separator 149 extends
144 back and forth using a suitable drive mechanism, such as an air bladder.
Figure 13 shows a left side perspective view of the carriage driver assembly 132, showing more clearly how a spacer element of the cap spacer 149 is arranged to move in and out (a direction generally perpendicular to the rods 134) along rods 149a in the cap separator housing 149. Each of the semicircular cuts of the spacer element can engage a corresponding slot of a cap 31 in a line 30 by extending forward when the cap 31 is appropriately positioned opposite the spacer 149 by the drive member 133 and carriage 146. With the member spacer coupled with covers 31, cover spacer 149 can be moved with carriage 146 as drive member 133 moves. Figure 14 shows a partial rear view of carriage driver assembly 132. In this embodiment, driver member 133 is moved to mounting location 145 of cassette 24 by a first air bladder 137 which expands to force the driver member 133 to move to the right in Figure 14. The driver element can be moved to the left by a second air bladder 138. Alternatively, the drive element 133 can be moved from back to front by means of one or more motors coupled to a linear drive gear assembly, such as a ball screw assembly (in which the carriage drive assembly is attached to a ball nut), or an assembly of, for example,
145 rack and pinion. Cap separator element 1491 1491 can be moved in and out of the cap separator housing by a third bladder, or alternatively, by a motor coupled to a linear drive assembly, as described above.
Figures 15-18 show another embodiment of a carriage driver assembly 132 and cap separator 149. As can be seen from the rear view of carriage driver assembly 132 of Figure 15, in this embodiment the driver element 133 is moved clockwise and counterclockwise by a 1321 screw drive. As can be seen from the right rear perspective view of the carriage driver assembly 132 of Figure 16, the spacer element is moved outward and inward by an air bladder 139, although other arrangements are possible as described above.
Figures 17 and 18 show left and right front perspective views of another embodiment for the separator element 1491 of the cap separator 149. The separator element 1491 in the embodiment shown in Figure 13 included only fork-shaped elements arranged to engage with a cap 31 of a solution line 30. In the embodiment of Figures 17 and 18, the spacer element 1491 includes not only the fork-shaped elements 60, but also swing arms 61 that are pivotally mounted to the spacer element 1491. As will be explained in more detail below, the swing arms 61 help to remove the pin caps 63 from cassette 24. Each of the arms
146 Oscillating 61 includes a solution line cap latch portion 61a and dowel cap latch portion 61b. The swing arms 61 are typically deflected to move so that the spigot cap latch portions 61b are located near the spacer element 1491, as shown in the swing arms 61 in Figure 18. However, when the lid 31 is received by a corresponding fork-shaped element 60, the solution line lid engaging portion 61a makes contact with the lid 31, causing the swing arm 61 to pivot so that the pin cap latch portion 61b moves away from the spacer element 1491, as shown in Figure 17. This position allows the pin cap engaging portion 61b to contact a pin cap 63, specifically a flange on the pin cap 63.
Figure 19 shows a front view of the spacer element 1491 and the location of various cross-sectional views shown in Figures 20-22. Figure 20 shows the swing arm 61 without pin cap 63 or solution line cap 31 located near the spacer element 1491. The swing arm 61 pivotally mounts to the spacer element 1491 at a point approximately halfway between the pin cap latch 61b and solution cap latch portion 61a. As mentioned before, the swing arm 61 is normally deflected to rotate in a counterclockwise direction as shown in Figure 20, so that the spigot cap engaging portion 61b is positioned
147 near the spacer element 1491. Figure 21 shows that the rocker arm 61 maintains this position (ie, with the spigot cap engaging portion 61b located near the spacer element 1491) even as the spacer element 1491 advances toward a dowel 63 in the absence 5 of a solution line cap 31 which engages with fork element 60. As a result, the swing arm 61 will not rotate clockwise or engage the spigot cap 63 unless a solution line cap 31 is present. Therefore, a spigot cap 63 that does not engage with a solution line cap 31 will not be removed from cassette 24.
Figure 22 shows an example in which a solution line cap 31 is engaged with the fork-shaped element 60 and contacts the solution line cap engaging portion 61a of the swing arm 61. This causes the rocker arm 61 rotates in a clockwise direction 15 (as shown in the Figure) and the spigot cap engaging portion 61b engages with the spigot cap 63. In this embodiment, engagement of portion 61b includes locating portion 61b adjacent a second flange 63a on spigot cap 63 so that when spacer element 1491 is moved to the right (as shown in Figure 22) , the pin cap engaging portion 61b will make contact with the second tab 63a and help pull the pin cap 63 from the corresponding pin 160. Note that the solution line cap 31 is made of a flexible material, such as silicone rubber, to allow a beard 63c
148 of pin cap 63 stretch hole 31b of cap 31 (see Figure 23) and be captured by an internal groove or circumferential depression within cap 31. A first tab 63b in pin cap 63 acts as a stop for the end of the solution line cap 31. In another example, the spigot cap 63 does not include a first tab 63b. The walls defining the slot or depression in the hole 31b of the cover 31 may be symmetrically or preferably asymmetrically arranged to conform to the shape of the beard 63c. (See Figure 33 for a cross-sectional view of the cap 31 and the groove or depression.) The second flange 63a in the stud cap 63 acts as a tooth with which the stud cap engaging portion 61b of the arm Oscillating 61 engages to provide additional pulling force to disengage pin cap 63 from pin 160, if necessary.
Figure 11-5 and Figure 11-6 show two different perspective views of another embodiment for the separator element 1491 of the cap separator 149. The separator element 1491 in the embodiment shown in Figure 13 uses fork-shaped elements 60 arranged to engage with a cap 31 of a solution line 30. In the embodiment shown in Figure 11-5, the spacer element 1491 not only includes the fork-shaped elements 60, but also includes a plurality of sensing elements 1112 and a plurality of swing arms 1114. The sensing elements 1112 and swing arms 1114 can be arranged in two parallel columns running vertically through the
149 separator element 1491. In one embodiment, each vertical column may contain five individual sensing elements 1112 and swing arms 1114, each positioned to generally align in a row corresponding to each of the fork-shaped elements 60. Each element of Detection 1112 can be mechanically connected or linked to one of the corresponding swing arms 1114. Additionally, the assembly comprising each sensing element 1112 and oscillating arm 1114 may include a bypass spring (not shown) that holds each oscillating arm 1114 deflected into a non-latching position and the sensing element 1112 in a position to be contacted. and moved by the presence of a solution line cap 31 on the fork-shaped element 60. Each sensing element 1112 can be moved and tilted towards the rear of the spacer element 1491 by contact with a corresponding solution line cap 31 on the fork-shaped element 60. Through the mechanical connection between sensing element 1112 and oscillating arm 1114, oscillating arm 1114 can pivot or laterally tilt toward pin cap 63 upon contact between solution line cap 31 and element detection 1112. As the swing arm 1114 rotates or tilts toward the stem cap 63, it can engage the second flange 63a on the stem cap 63, allowing the spacer assembly to remove the stem cap 63 from its corresponding stem.
150
Figures 11-7A through 11-7C illustrate the relationship between sensing element 1112 and a solution line cap 31, and between swing arm 1114 and spike cap 63. Figure 11-7C shows the sensing element 1112 and the swing arm 1114 in the absence of a spigot cap 63 and the solution line cap 31. As shown in Figure 11-7B, an outer flange 31c of the solution line cap 31 has a diameter large enough to contact the sensing element 1112. As shown in Figure 11-7A, in the absence of a solution line cap 31, the mere presence of pin cap 63 does not contact detection element 1112 enough to displace it and cause it to rotate away from pin cap 63. As shown in Figure 11-7B, the displacement of the sensing element 1112 causes the oscillating arm 1114 to rotate or tilt towards the pin cap 63, finally to the point of being positioned adjacent to the tab 63a of the pin cap 63 . As shown in Figure 11-7A, when the swing arm 1114 is in an undeployed position, it can clear the outer circumference of the second flange 63a of the spike cap 63 by a predetermined amount (eg 0.10 cm). Upon movement of the swing arm 1114 in an unfolded position, its sliding scale can be configured to provide a slight compressive force against its corresponding spigot cap 63 to ensure a secure latch.
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Once an oscillating arm 1114 is placed adjacent to the tab 63a of the spike cap 63, movement of the spacer element 1491 to the right side will engage the spike cap 63 by means of the tab 63a and help pull the spike cap 63 from its corresponding spike 160. In the absence of a solution line and its related solution line cap 31, the spacer element 1491 will not remove the corresponding pin cap 63, keeping its related pin 160 sealed. Thus, less than the maximum number of spikes in cassette 161 can be accessed when less than the maximum number of solution lines is to be used.
Figure 23 shows an exploded close-up view of the connector end 30a of a solution line 30 with the cap 31 removed. (In Figure 23, caps 31 are shown without a finger pull ring as shown in Figure 24 for clarity. A pull ring need not be present for cap 31 operation with cycler 14. It may be useful, however, to allow an operator to manually remove the cap 31 from the terminal end of solution line 30, if necessary). In this illustrative embodiment, the indicator on the indicator ruler 33 has an annular shape that is dimensioned and configured to fit within a corresponding groove of carriage 146 when mounted as shown in Figures 10 and 11. Of course, the indicator it can take any suitable form. The cap 31 is arranged to fit over the end distal end of the connector end 30a, which has a hole
152 internal, seals, and / or other features to allow a leak-free connection with a spigot 160 in a cassette 24. The end of connector 30a may include a pierceable wall or septum (not shown - see Figure 33, item 30b) that prevents leakage of solution into line 30 at end of connector 30a, even if cap 31 is removed. The wall or septum may be perforated by dowel 160 when connector end 30a is attached to cassette 24, allowing flow from line 30 to cassette 24. As described above, cover 31 may include a slot 31a that is engaged. by a fork-shaped element 60 of the cap separator 149. The cap 31 may also include a hole 31b which is arranged to receive a pin cap 63. The hole 31b and the cap 31 can be arranged so that, with the cap separator 149 engaged with the slot 31a and the pin cap 63 of a pin 160 received in the hole 31b, the cap 31 can hold the pin cap 63 suitably so that when carriage 146 / cap separator 149 pulls cap 31 away from cassette 24, pin cap 63 is removed from pin 160 and is carried by cap 31. This removal can be aided by swing arm 61 which hooks with second flange 63a or other feature on spigot cap 63, as described above. Subsequently, cap 31 and pin cap 63 can be removed from connector end 30a and line 30 attached to pin 160 by carriage 146.
153
Solution Line Connector Heater
In one embodiment, a connector heater may be provided near the indicator region 33 of solution lines 30. The connector heater can control the temperature of the connector end 30a and in particular the pierceable wall or septum 30b to limit the force of carriage required to join solution lines to pins 160 on cassette 24. There may be enough variation in ambient temperature to affect the hardness of the wall or pierceable septum 30b of the end of the solution line connector 30a, which in turn may affect the performance of carriage 146 in joining with spigot 160 to connector end 30a of solution line 30. For example, at low ambient temperatures, the increased hardness of the pierceable wall or septum 30b may require greater force for pin 160 to penetrate. On the other hand, at higher ambient temperatures, the pierceable wall or septum may be so smooth as to deform rather than separate when in contact with pin 160.
The temperature of the connector ends 30a can be controlled in many ways, which may include placing a heating element at an appropriate location (for example, at or near location 2807 above door 141), installing a temperature detector to monitor the temperature of connector ends 30a and use a controller to receive temperature data and modulate the operation of the heating element. The temperature can be measured by means of a
154 temperature sensing element mounted on spacer element 1491 or on carriage 146. Alternatively, the end temperature of connector 30a can be determined using an infrared (IR) detector adjusted to measure the surface temperature of end of connector 30a.
The controller can be a software process in automation computer 300. Alternatively, the controller can be implemented in hardware interface 310. The controller can modulate the energy sent to a resistance heater, for example, in one of many ways. . For example, the controller can send a PWM signal to a MOSFET that can modulate the flow of electrical energy to the resistance heater. The controller can control the measured temperature to the desired temperature through many algorithms. An exemplary algorithm includes a proportional-integral (Pl) feedback loop on the measured temperature to establish the energy of the heater. Alternatively, the heater power can be modulated in an open loop algorithm that sets the heater power based on the measured ambient temperature.
In another embodiment, the temperature of the connector end 30a can be controlled by mounting a radiant heater on door 141 at location 2807, for example, and pointing it toward the connector ends. Alternatively, the temperature of the connector ends can be controlled by mounting a thermoelectric element at location 2807, for example, on door 141. The thermoelectric element can provide
155 either heating or cooling the area around the ends of the connector when mounted on the cart 146. The radiant heater or thermo-electric element can be modulated by means of a controller to maintain the temperature within a given range. The preferred temperature range for the end of connector 30a depends on the material comprising the pierceable wall or septum, and can be empirically determined. In one embodiment, the pierceable wall is PVC and the preferred temperature range is set at about 10 ° C to 30 °, or more preferably at a temperature range of about 20 ° to 30 ° C.
In one embodiment, the connector heater near the indicator region 33 can be used after the door is closed and before solution lines 30 are attached to cassette 24. Automation computer 300 or a controller enables the connector heater if the temperature measured near connector 30a is outside a preferred range. The automation computer 300 or a controller may delay the auto-connect process until the measured temperature is within the preferred range. The connector heater can be disabled after the auto-connect process is complete.
Once the treatment is complete, or line 30 and / or cassette 24 are ready to be removed from cycler 14, cap 31 and attached pin cap 63 can be mounted again on pin 160 and line 30 before door 141 is allowed to open and cassette 24 and line 30
156 are removed from cycler 14. Alternatively, cassette 24 and solution containers with lines 30 can be removed in cycler block 14 without reassembling cap 31 and attached spigot cap 63. An advantage of this approach includes a process removal is simplified, and any possible fluid leakage in the cycler or surrounding area is avoided by improperly reassembling or improperly sealing the caps.
Figures 24-32 show a perspective view of carriage 146, cap separator 149 and cassette 24 during a line assembly and automatic connection operation. Door 141 and other components of the cycler are not shown for clarity. In Figure 24, carriage 146 is shown in a folded position, as if door 141 opened in the position shown in Figure 8. Lines 30 and cassette 24 are located to be lowered on door 141. In Figure 25, lines 30 are loaded onto carriage 146 and cassette 24 is loaded at mounting location 145. At this point, door 141 can be closed to prepare the cycler for operation. In Figure 26, door 141 is closed. The identifiers or indicators located in the region of indicator 33 on lines 30 can be read to identify various line characteristics so that cycler 14 can determine which solutions, how much solution, etc., are loaded. In Figure 27, carriage 146 has been moved to the left, hooking lids 31 on lines 30 with corresponding dowel covers 63 on cassette 24. During movement, the drive member 133 engages the cap separator 149 and moves the cap separator
157 tops 149 left too. However, the lid separator 149 remains in a retracted position. In Figure 28, the cap separator 149 is moved forward to engage the fork-shaped elements 60 with the caps 31, thereby engaging the caps 31 that have been coupled to the stud caps 63. If present, the arms Oscillating 61 can be moved to a latched position with respect to pin caps 63. Next, as shown in Figure 29, carriage 146 and cap separator 149 are moved to the right, away from cassette 24 to pull caps 31 and pin caps 63 from corresponding pins 160 in cassette 24 It is during this movement that the swing arms 61, if present, can assist in pulling the pin caps 63 out of the cassette 24. In Figure 30, cap separator 149 has stopped moving to the right, while carriage 146 continues to move away from cassette 24. This causes connector ends 30a of lines 30 to be pulled from caps 31, leaving the caps 31 and spigot caps 63 mounted on the cap separator 149 by means of the fork-shaped elements 60. In Figure 31, the cap separator 149 retracts, clearing a path for carriage 146 to move back to cassette 24. In Figure 32, carriage 146 moves to cassette 24 to engage connector ends 30a of lines 30 with corresponding pins 160 of cassette 24. Carriage 146 may remain in this position during operation of the cycler. Once the treatment ends, the movements shown in the
158
Figures 24-32 can be reversed to re-cap pins 160 and solution lines 30 and remove cassette 24 and / or lines 30 from cycler 14.
To better illustrate the removal of caps 31 and spigot caps 63, Figure 33 shows a cross-sectional view of cassette 24 at five different stages of line connection 30. On top spike 160, spigot cap 63 is still in place on spike 160 and solution line 30 is located away from cassette 24, as in Figure 26. At the second dowel 160 below the upper one, the solution line 30 and cap 31 are hooked onto the pin cap 63, as in Figures 27 and 28. At this point, cap separator 149 can engage cap 31 and spigot cap 63. On the third spigot 160 from the top, the solution line 30, cap 31 and spigot cap 63 have been moved away from the cassette 24, as in Figure 29. At this point, the cap separator 149 You can stop the movement to the right. On the fourth spike 160 from the top, solution line 30 continues to move to the right, removing cap 31 from line 30, as in Figure 30. Once caps 31 and 63 are retracted, the solution line 30 moves to the left to fluidly connect the connector end 30a of line 30 to pin 160, as in Figure 32.
Various detectors can be used to help verify that carriage 146 and cap separator 149 are fully moved to their expected positions. In one embodiment, the carriage driver assembly 132 can be equipped with six Hall effect detectors (not shown): four for carriage 146 and two for cap separator 149. A
159 First cap separator detector may be located to detect when the cap separator 149 is fully extended. A second cap separator detector may be located to detect when the cap separator 149 is fully extended. A first carriage detector may be located to detect when carriage 146 is in the starting position, that is, in position to allow cassette 24 and lines 30 to be loaded. A second carriage detector may be located to detect when carriage 146 is in position to engage pin caps 63. A third carriage detector may be located to detect when carriage 146 has reached a position to remove caps 31 from lines 30. A fourth carriage detector may be located to detect when carriage 146 has been moved to a position to engage the ends of connector 30a of lines 30 with corresponding pins 160 of cassette 24. In other embodiments, a single detector can be used to detect more than one of the carriage positions described above. The lid and carriage separator detectors can provide input signals to an electronic control board (auto-connect board), which in turn can communicate specific confirmation or error codes to the user via user interface 144.
Figure 11-6 shows a perspective view of an alternate embodiment of carriage driver assembly 132. Carriage driver assembly 132 in the embodiment shown in Figure 12 included only driver element 133, rods 134, tabs. 136, and the
160 window 136. In the embodiment of Figure 11-6, the carriage driver assembly 132 not only includes the driver assembly 133, the rods 134, the tabs 136, and the window 136, but may also include a vertical column of AutoID 1116 view boxes. View boxes 1116 can be placed directly adjacent to window 136. Also, the view boxes 1116 can be positioned and configured such that the horizontal axis of each of the five slots 1086 that is located on the cart 146 runs through the center of a corresponding view box 1116 when the cart 146 is move either right or left along guides 130. The 1116 view boxes can allow the AutoID 1104 camera, which is attached to the 1106 camera board, to detect if the solution line 31 caps are placed on lines 30 before the solution lines engage with the pin cap 63. This can confirm that the user has not removed caps 31 prematurely. Once the presence or absence of caps 31 is determined, camera 1104 can provide an input signal corresponding to an electronic control board (referred to as the auto-connect board later in the specification), which in turn can communicate specific confirmation or error codes regarding the presence of caps 31 on lines 30 to the user via user interface 144.
In accordance with another aspect of the description, the carriage driver assembly 132 may include an 1118 auto connect board. The 1118 auto connect board can be attached to the top of the assembly.
161 of the carriage driver 132, and can be extended to the full length of assembly 132. In this illustrative embodiment, there may also be an LED 1120 mounted to the auto connect board 1118. LED 1120 can be located in a fixed position directly above the fork-shaped elements 60. Also, LED 1120 can be directed in such a way that the light emitted from LED 1120 travels downward through separator element 1491. In accordance with another aspect of the present disclosure, carriage impeller assembly 132 may also include a fluid board 1122. Fluid dash 1122 can be attached to the bottom of carriage impeller assembly 132, and the length can also be extended from assembly 132. In this illustrative embodiment, a receiver 1124 (not shown) may be mounted to fluid board 1122 at a location directly below LED 1120, which is mounted to auto-connect board 1118. Thus, LED 1120 can emit light through fork-shaped elements 60, and if light is detected by receiver 1124 then there are no solution line caps 31 on separator element 1491, however, if the light is interrupted on its way to receiver 1124 then there may be a cover 31 on spacer element 1491. This combination of LEDs 1120 and receiver 1124 enables the detection of caps 31 that may have been inadvertently left on the separator element 1491 by either the user or the cycler 14. According to one aspect of the description, the fluid board 1122 It may also have the ability to detect moisture, seepage, or any other liquid that may be
162 present inside carriage driver assembly 132, which could potentially cause failure of cycler 14.
There may be an advantage to adjusting the force with which carriage 146 engages spigot caps 63, depending on how many lines 30 are being installed. The force required to complete a connection to cassette 24 increases with the number of caps 31 that must be coupled to the stud caps 63. The detection device for detecting and reading information from the line indicators in the indicator regions 33 can also be used to provide the data required to adjust the force applied to the driving element 133. The force can be generated by many devices, including, for example, the first air bladder 137, or a linear actuator such as a motor / ball screw. An electronic control board (such as the auto connect board) can be programmed to receive input from the line detection detector (s), and send an appropriate control signal either to the motor of a linear actuator, or to the Pneumatic valve that controls inflation of the air bladder 137. Controller 16 can control the degree or speed of movement of driver element 133, for example by modulating the voltage applied to the motor of a linear actuator, or by modulating the pneumatic valve that controls bladder inflation 137.
In accordance with one aspect of the present disclosure, it may be necessary for the carriage driver assembly 132 to be capable of generating a force of at least 550 N (124 Ibf) on carriage 146, in order to
163 hook the membrane ports with the dowels 160. This force should be measured in the direction of the carriage of the diaphragm port nailed to the cassette 24. The maximum force required to nail a sterile PVC membrane port onto the dowel 160 can be 110 N. Additionally, the maximum force required to drive a sterile JPOC membrane port onto pin 160 can be 110 N. These force requirements ensure that the carriage drive assembly 132 can drive five JPOC ports. In an alternative embodiment, the strength requirement of the PVC port can be further lowered based on current insertion forces.
The aspect of the invention whereby the caps 31 on the lines are removed together with the caps 63 on the pins 160 of the cassette 24 can provide other advantages in addition to simplicity of operation. For example, since pin caps 63 are removed by hooking them with a cap 31 on a line 30, if there is no line 30 mounted in a particular slot in carriage 146, the pin cap 63 in that position will not will be removed. For example, although cassette 24 includes five pins 160 and corresponding pin caps 63, cycler 14 may operate with four or fewer (even without) lines 30 associated with cycler 14. For those slots in carriage 146 where no lines 30 is present, there will be no cap 31, and therefore there will be no mechanism by which a pin cap 63 in that position can be removed. Therefore, if there is no line 30 connected to a particular pin 160, the cap 63 on that pin 160 may
164 stay in place while using cassette 24. This can help prevent leakage at pin 160 and / or contamination at pin 160.
Cassette 24 in Figure 33 includes new features that are different from those shown, for example, in the mode shown in Figures 3, 4, and 6. In the mode of Figures 3, 4, and 6, the bag port of Heater 150, drain line port 152 and patient line port 154 are arranged to have a center tube 156 and skirt 158. However, as mentioned above and shown in Figure 33, ports 150, 152, 154 may include only center tube 156 and not skirt 158. This is also shown in Figure 34. The mode illustrated in Figure 34 includes raised ribs formed on the outer surface of left side pump chamber 181. The raised ribs can also be provided in the right-side pump chamber 181, and can provide additional points of contact of the outer walls of the pump chambers 181 with the mechanism in the door 141 at the mounting location of the cassette 145, which presses the cassette against the control surface 148 when the door 141 is closed. Raised ribs are not required, and instead pump chambers 181 may have no ribs or other features, as shown for pump chamber 181 on the right hand side in Figure 34. Similarly, pins 160 in the embodiment of Figures 3, 4, and 6 does not include a skirt or similar feature at the base of spike 160, while the embodiment in Figure 33 includes a skirt 160a. This is also shown in Figure 34. The skirt
165
160a may be arranged to receive the end of pin cap 63 in a depression between skirt 160a and pin 160, helping to form a seal between pin 160 and pin cap 63.
Another inventive feature shown in Figure 33 relates to the arrangement of the distal tip of the spike 163 and the lumen 159 through the spike 160. In this regard, the distal tip of the spike 160 is located at or near the longitudinal axis of pin 160, which generally runs along the geometric center of pin 160. The location of the distal tip of the spike 160 on or near the longitudinal axis can help facilitate alignment tolerances when the spike 160 is engaged with a corresponding solution line 30 and help the spike 160 pierce a septum or membrane 30b in connector end 30a of the line
30. As a result, lumen 159 of pin 160 is generally located outside the longitudinal axis of pin 160, for example, near the bottom of pin 160 as shown in Figure 33 and as shown in an end view of a spike 160 in Figure 35. Also, the distal end of stem 160 has a somewhat reduced diameter compared to more proximal portions of stem 160 (in this embodiment, stem 160 actually has a change in diameter to about 2/3 of the length of stem 160 from the body 18). The reduced diameter of pin 160 at the distal end can provide clearance between pin 160 and the inner wall of line 30, thus allowing septum 30b a space to fold back to be placed between
166 dowel 160 and line 30 when pierced by dowel 160. Staggered feature 160b on dowel 160 (shown, for example, in Figure 35A may also be arranged to engage line 30 at the location where the septum is 30b is connected to the inner wall of line 30, thereby improving a seal formed between line 30 and dowel 160.
In another embodiment, as shown in Figure 35A, the length of the base 160c of the pin 160 can be shortened to reduce the force required to remove the pin cap 63 from the pin 160, or to reduce the force required to nail the end of the connector 30a of the solution line 30. Shortening the base 160c reduces the area of friction contact between the pin 160 and its cap 63, or between the pin 160 and the inner surface of the end of the connector 30a. Furthermore, the skirt 160a at the base of the pin 160 can be replaced by individual posts 160d. Posts 160d allow pin cap 63 to seat properly on pin 160 while also allowing more complete circulation of sterilizing fluid or gas around pin 160 during the sterilization process before or after packaging the package of dialysate fluid supply 12.
To take full advantage of the modality shown in Figure 35A, a spigot cap 64, as shown in Figure 35B can be used. A skirt 65 at the base of pin cap 64 is constructed to fit snugly over posts 160d at the base of pin 160 shown in Figure 35A. In addition, the ribs
167 interrupted 66, 67 within the inner circumference of the base of the stem 160 can provide a snug fit between the stem cap 64 and the base 160c of the stem 160, while also allowing sterilizing gas or fluid to penetrate more distally based on a spigot cap 160. As shown in Figure 35C, in a cross-sectional view of the stem cap 64, a set of three ribs 66, 67, 68 can be used to provide a snug fit between the stem cap 64 and the base 160c of pin 160. In one embodiment, rib 66 and rib 67 have gaps or spaces 66a and 67a along their circumference to allow gas or fluid external to the cassette to flow over base 160c of pin 160. A third rib 68 may be circumferentially intact to make a sealing engagement between pin cap 64 and base 160c of pin 160, sealing base 160c from the rest of the outer surface of pin 160. In other embodiments, the ribs within pin cap 64 can be oriented longitudinally rather than circumferentially or in any other orientation to provide a snug fit between pin cap 64 and pin 160, while also allowing an external gas or fluid to make contact with the outside of the base 160c of the spike 160. In the embodiment shown, for example, the outer surface of the cassette, the pin cap and most of the base 160c of the pin 160 can be sterilized by exposing the cassette externally to ethylene oxide gas. Since the diameter of the stepped feature 160b and the distal end of the stem
168
160 are smaller than the inside diameter of the overlapping portion of the stem cap 64, any gas or fluid entering the lumen of the stem from within the cassette can reach the outer surface of the stem 160 to the sealing rib 68. Thus any sterilization gas such as ethylene oxide that enters the fluid passages of the cassette can reach the rest of the external surface of pin 160. In one embodiment, gas can enter the cassette through a vented cap, for example, at the end of patient line 34 or drain line 28.
Pin cap 34 may include 3 or more centering ribs 64D that contact the end of pin 160. Ribs 64D are oriented along the main access of pin cap 34 and are located near the closed end of dowel cap 34. Preferably there are at least three ribs 63D to center the closed end of the lid over the dowel without over-constraining the lid / dowel orientation. Dowel Cap 64 includes a tapered end with a blunt tip to facilitate penetration of Dowel Cap 34 into hole 31b of Solution Cap 31. The tapered end will guide Dowel Cap 34 if it is misaligned with the hole 31b. The blunt tip avoids snagging with the solution cap 31 as opposed to a sharp tip that could trap the inner edge of the hole 31b and dig into the solution cap material. In contrast, a blunt tip can slide past the edges of the hole
31b.
169
Once cassette 24 and lines 30 are loaded into cycler 14, cycler 14 must control the operation of cassette 24 to move fluid from solution lines 30 to warmer bag 22 and the patient. Figure 36 shows a plan view of the control surface 148 of cycler 14 that interacts with the pump chamber side of cassette 24 (eg, shown in Figure 6) to cause fluid pumping and path control. flow in cassette 24. When at rest, the control surface 148, which can be described as a type of packaging, and comprises a silicone rubber sheet, can be generally flat. Valve control regions 1481 may (or may not) be defined on control surface 148, for example, by marking, groove, rib, or other feature within or on the sheet surface, and be arranged to be movable in a direction generally transverse to the plane of the sheet. By moving in / out, valve control regions 1481 can move associated portions of membrane 15 on cassette 24 to open and close respective valve ports 184, 186, 190, and 192 of cassette 24, and thus controlling flow in cassette 24. Two larger regions, pump control regions 1482, may also be movable to move associated shaped portions 151 of membrane 15 cooperating with pump chambers 181. Like configured portions 151 of membrane 15, pump control regions 1482 may be configured in a way to correspond to the shape of pump chambers 181 when control regions 1482
170 they are extended within the pump chambers 181. In this way, the portion of the control sheet 148 in the pump control regions 1482 does not necessarily have to be stretched or otherwise elastically deformed during the pumping operation.
Each of regions 1481 and 1482 may have an associated vacuum or evacuation port 1483 that can be used to remove all or substantially all of any air or other fluid that may be present between membrane 15 of cassette 24, and the surface of Control 148 of cycler 14, for example, after cassette 24 is loaded into cycler 14 and door 141 is closed. This can help ensure close contact of the membrane 15 with the control regions 1481 and 1482, and help control the delivery of desired volumes with pump operation and / or the open / closed state of the various valve ports. Note that vacuum ports 1482 are formed in places where control surface 148 will not be pressed into contact with a wall or other relatively stiff feature of cassette 24. For example, in accordance with an aspect of the invention, one or both of the cassette pump chambers may include a vacuum vent free space region formed adjacent to the pump chamber. In this illustrative embodiment as shown in Figures 3 and 6, the base member 18 may include vacuum or extension vent port space features 182 (eg, depressed areas that are fluidly connected to the pump chambers) adjacent and outside the oval-shaped depressions that form the
171 Pump chambers 1483 for pump control region 1482 to remove any air or fluid between membrane 15 and control surface 148 (eg, due to rupture of membrane 15) without obstruction. The extension feature may also be located within the perimeter of pump chamber 181. However, the location of the vent port feature 182 outside the perimeter of the pump chamber 181 may retain more of the volume of the pumping chamber for pumping liquids, for example, allows the full footprint of the pump chamber 181 is used to pump the dialysate. Preferably, extension feature 182 is located in a vertically lower position relative to pump chamber 181, so that any liquid leaking between membrane 15 and control surface 148 is removed through the vacuum port 1483 at the first opportunity. Similarly, the vacuum ports 1483 associated with valves 1481 are preferably located in a vertically lower position relative to valves 1481.
Figure 36A shows that control surface 148 can be constructed or molded to have a rounded transition between base member 1480 of control surface 148 and its valve and pump control regions 1481, 1482. Joints 1491 and 1492 they can be molded with a small radius for transition from base member 1480 to valve control region 1481 and pump control region 1482, respectively. A smooth or rounded transition helps prevent premature fatigue and rupture of the material comprising the
172 control surface 148, and can improve its longevity. In this embodiment, channels 1484 leading from vacuum ports 1483 to pump control regions 1482 and valve control regions 1481 may need to be elongated to somewhat accommodate the transition feature.
Control regions 1481 and 1482 can be moved by controlling pneumatic pressure and / or volume on one side of control surface 148 opposite cassette 24, for example, on a rear side of the rubber sheet that forms the surface of control 148. For example, as shown in Figure 37, control surface 148 may be supported by a matching or pressure supply block 170 that includes control chambers or depressions 171A located in association with each control region 1481, and chambers control depressions 171B located in association with each control region 1482, and which are isolated from each other (or at least can be independently controlled from each other if desired). The pairing surface or pressure supply block 170 forms a pairing interface with cassette 24 when cassette 24 is depressed in operative association with control surface 148 backed by pairing block 170. The control or depression chambers of the matching block 170 are thus coupled to the complementary or pumping valve chambers of the cassette 24, interspersing the control regions 1481 and 1482 of the control surface 148 adjacent to the matching block 170, and the associated regions of membrane 15 (such as the
173 Shaped portion 151) adjacent to cassette 24. Air or other control fluid can be moved into or out of control chambers or depressions 171A, 171B of matching block 170 for regions 1481, 1482, thereby moving control regions 1481 , 1482 as desired to open / close the valve ports of cassette 24 and / or perform the pumping action on pumping chambers 181. In an illustrative embodiment as shown in Figure 37, the control chambers 171A may be arranged as cylindrical regions supporting each of the valve control regions 1481. The control chambers or depressions 171B may comprise voids or ellipsoid, ovoid, or hemispherical depressions that support the control regions of the 1482 pump. Fluid control ports 173A can be provided for each control chamber 171A so that cycler 14 can control fluid volume and / or fluid pressure in each of valve control chambers 1481. Ports of Fluid control 173C can be provided for each control chamber 171B so that cycler 14 can control fluid volume and / or fluid pressure in each of volume control chambers 1482. For example, the pairing block 170 can be paired with a manifold 172 that includes various ports, channels, openings, voids, and / or other features that communicate with control chambers 171 and allow air / vacuum pressure to be applied to control chambers 171. Although not shown, pneumatic / vacuum pressure control can be performed in any suitable way, such as
174 through the use of controllable valves, pumps, pressure detectors, accumulators, etc. Of course, it should be understood that the control regions 1481, 1482 can be moved in other ways, such as by gravity-based systems, hydraulic systems, and / or mechanical systems (such as by linear motors, etc.), or by a combination of systems including pneumatic, hydraulic, gravity-based and mechanical systems.
Figure 37A shows an exploded view of an integrated 2700 pressure distribution module or assembly for use in a fluid flow control apparatus for operating a pump cassette, and suitable for use as a 172 pressure distribution manifold and block. cycler pairing 170 14. Figure 37B shows a view of an integrated 2700 module comprising a pneumatic manifold or block, ports for supply pressures, pneumatic control valves, pressure detectors, a matching or pressure supply block, and a control or actuator surface. including regions comprising flexible membranes to drive pumps and valves on a pump cassette. The integrated module 2700 can also include reference chambers within the pneumatic manifold for an FMS volume measurement process to determine the volume of fluid present in a pump chamber of a pump cassette. The integrated module may also comprise a vent port, and a set of paths or channels from interfaces between the actuator and the flexible pump, and
175 valve from a pump cassette to a fluid trap and a liquid detection system. In some embodiments, the pneumatic manifold can be formed as a single block. In other embodiments, the pneumatic manifold can be formed of two or more manifold blocks paired together with gaskets positioned between the manifold blocks. The 2700 integrated module occupies a relatively small space in a fluid flow control apparatus, and eliminates the use of flexible tubes or conduits connecting the manifold ports to the corresponding ports of a pressure supply module or block paired with a pump cassette. Among other possible advantages, the 2700 integrated module reduces the size and assembly cost of the pneumatically operated assembly of a peritoneal dialysis cycler, which can result in a smaller and less expensive cycler. Additionally, the short distances between the pressure or vacuum distribution ports on the pressure distribution manifold block and the corresponding pressure or vacuum supply ports on a matching pressure supply block, along with the stiffness of the conduits connecting ports, can improve the sensitivity of a attached pump cassette and the precision of cassette pump volume measurement processes. When used in a peritoneal dialysis cycler 14, in one embodiment, an integrated module comprising a metal pressure distribution manifold paired directly with a metal pressure supply block can also reduce any temperature difference between control volume 171B and
176 reference chamber 174 of cycler 14, which can improve the accuracy of the pump volume measurement process.
An exploded view of the 2700 integrated module is presented in Figure 37A. The actuator surface, mounted on a matching block or pressure supply block, is analogous or equivalent to packing or control surface 148, which includes flexible regions arranged to move back to front to pump fluid and / or open and close the valves by pushing or pulling on a membrane 15 or a pump cassette 24. With respect to cycler 24, control surface 148 is actuated by means of positive and negative pneumatic pressure supplied to control volumes 171A, 171B behind control regions 1481, 1482. Control surface 148 is attached to the block pressure supply valve or matching block 170 fitting tightly on a raised surface 2744 on the front surface of matching block 170 with a lip 2742. Matching block 170 may include one or more surface depressions 2746 to align with and support the oval curved shape of one or more corresponding pump control surfaces 1482, forming a pump control chamber. A similar arrangement, with or without a surface depression, can be included in the formation of a valve control region 171A to align with a corresponding control surface 1481 to control one or more valves in a pump cassette. Matching block 170 may further include grooves 2748 on depression surface 2746 of the
177 match block 170 behind the pump control surface 1482 to facilitate the flow of control fluid or gas from port 173C to the entire rear surface of the pump control surface 1482. Alternatively, instead of having slits 2748, depression 2746 can be formed with a rough surface or a tangentially porous surface.
Matching block 170 connects pressure distribution manifold 172 with control surface 148, and supplies pressure or vacuum to various control regions on control surface 148. Pairing block 170 can also be referred to as a pressure supply block, as it provides pneumatic lines to supply pressure and vacuum to valve control regions 1481 and pump control regions 1482, vacuum to vacuum ports. 1483 and connections from 171B pump control volumes to pressure detectors. Ports 173A connect valve control volumes 171A to pressure distribution manifold 172. Ports 173C connect pump control volume 171B to pressure distribution manifold 172. Vacuum ports 1483 are connected to pressure distribution manifold 172 via ports 173B. In one embodiment, ports 173B extend above the surface of pressure supply block 170 to pass through control surface 148 to provide a vacuum at port 1483 without pulling control surface 148 over port 173B and blocking flow.
178
Pressure supply block 170 is attached to the front face of pressure distribution manifold 172. Ports 173A, 173B, 173C are aligned with the pneumatic circuits on pressure distribution manifold 172 that connects valve ports 2714. In one example, the pressure supply block 170 is paired with the pressure distribution manifold 172 with a front flat gasket 2703 fastened therebetween. Block 170 and manifold 172 are mechanically fastened together, which in one embodiment occurs through the use of bolts 2736 or other types of fasteners. In another example, instead of a flat gasket 2703, the compatible elements are placed in or molded into either the pressure supply block 170 or the pressure distribution manifold 172. Alternatively, the pressure supply block 170 can be bonded to the pressure distribution manifold 172 by means of an adhesive, double-sided tape, friction welding, laser welding, or other linking method. Block 170 and manifold 172 can be formed of metal or plastic, and bonding methods will vary depending on the material.
Pressure distribution manifold 172 contains ports for 2710 pneumatic valves, reference chambers 174, a 1722 fluid trap, and 2700 integrated module connections pneumatic circuits provide pneumatic connections between pressure vessels, valves, and contains 2714 ports receiving 2710 multiple cartridge valves. 2710 cartridge valves include, but are not limited to, 2660 binary valves that control flow to valve control volumes
179
171 A, Binary Valves X1A, X1B, X2, X3 that control flow to pump control volumes 171B, and Binary Valves 2661-2667 that control flow to bladders 2630, 2640, 2650, and pressure reservoirs 2610 , 2620. Cartridge valves 2710 are depressed into valve ports 2714 and electrically connected to hardware interface 310 via circuit board 2712.
Pneumatic circuits in the pressure distribution manifold
172 can be formed with a combination of slits or grooves 1721 on the front and rear faces and approximately perpendicular holes that connect the grooves 1721 on one face to the valve ports 2714, the fluid trap 1722 and to the slits and ports on the opposite face . Some slits 1721 can be connected directly to reference chambers 174. A single perpendicular orifice can connect a slit 1721 to multiple valve ports 174 that are closely spaced and staggered. The sealed pneumatic lines are formed when the grooves 1721 are isolated from each other by means of an example of the front flat packing 2703 as shown in Figure 37A.
The presence of liquid in fluid trap 1722 can be detected by a pair of 2732 conductivity probes. 2732 conductivity probes slide through a 2704 back pack, 2730 back plate, and 2750 holes before entering the Fluid trap 1722 in pressure distribution manifold 172.
180
Backplate 2730 seals reference volumes 174, slits 1721 on back of pressure distribution manifold 172, and provides ports for 2740 pressure detectors and ports for 2734 pressure and vacuum lines and vents 2732 In one example, the pressure detectors can be IC ICs soldered to a single 2740 board and pressed as a group against the back pack 2704 on the 2730 back plate. In one example, bolts 2736 embrace back plate 2730, pressure distribution manifold 172, and pressure supply block 170 along with gaskets 2703, 2702 therebetween. In another example, the back plate 2730 can be linked to the pressure distribution manifold 172 as described above. The 2700 assembled integrated module is presented in Figure 37C.
Figure 37C presents a schematic of the pneumatic circuit in the 2700 integrated manifold and the pneumatic elements outside the manifold. The 2600 pump produces vacuum and pressure. The 2600 pump is connected via 3-way valves 2664 and 2665 to a vent 2680, and the negative or vacuum tank 2610 and the positive tank 2620. The pressure in the positive and negative tanks 2620, 2610 is measured respectively by means of detectors pressure 2678, 2676. Hardware interface 310 controls the speed of pump 2600 and the position of 3-way valves 2664, 2665, 2666 to control the pressure in each tank. The bladder of the self-connecting spacer 2630 is connected via the 3-way valve
181 either to the positive pressure line 2622 or to the vacuum or negative line 2612. The automation computer 300 commands the position of the valve 2661 to control the location of the separator element 1461. The occluder bladder 2640 and the piston bladder 2650 They are connected via 3-way valves 2662 and 2663 to either the 2622 pressure line or the 2680 vent. Automation computer 300 instructs valve 2662 to connect the piston bladder to pressure line 2622 after gate 141 closes to securely engage cassette 24 against control surface 148. Occluder bladder 2640 is connected to pressure line 2622 via valve 2662 and restriction 2682. Occluder bladder 2640 is connected to vent 2680 via valve 2662. Orifice 2682 advantageously slows the filling of the bladder from occluder 2640 which retracts occluder 147 to maintain pressure in pressure line 2622. High pressure in pressure line 2622 keeps the various valve control surfaces 171A actuated and the piston bladder against cassette 24, which prevents flow to or from the patient while occluder 147 is opened. Conversely, the connection from the bladder of the occluder 2640 to the vent 2680 is not restricted, so that the occluder 147 can be closed quickly.
Valve control surfaces 1481 are controlled by pressure in valve control volume 171 A, which in turn is controlled by the position of 3-way valves 2660. Valves 2660 can be controlled individually via automation computer commands 300 passed to hardware interface 310.
182
Valves that control pumping pressures in pump control volumes 171B are controlled with X1A, X1B 2-way valves. Valves X1A, X1B in one example can be controlled via hardware interface 310 to achieve a pressure ordered by automation computer 300. The pressure in each control chamber of pump 171B is measured by means of 2672 detectors. The pressure in the reference chambers is measured by means of 2670 detectors. 2-way valves X2, X3 respectively connect reference chamber 174 to pump control chamber 171B and vent 2680.
Fluid trap 2622 is connected to vacuum line 2612 during operation as explained elsewhere in this application. The fluid trap is connected via several lines to ports 173B in pressure supply block 170. The pressure in the fluid trap is monitored by means of pressure detector 2674 which is mounted on backplate 2730.
Vacuum ports 1483 can be used to separate membrane 15 from control surface 148 at the end of therapy before or during door opening. The vacuum provided by the negative pressure source to the vacuum ports 1483 hermetically engages the membrane 15 to the control surface 148 during therapy. In some cases a substantial amount of force may be required to separate the membrane control surface from cassette 15, preventing door 141 from rotating freely in the open position, even when application of
183 vacuum is discontinued. Thus, in one embodiment, the pressure distribution module 2700 is configured to provide a valved channel between the positive pressure source and the vacuum ports 1483. Providing positive pressure at the vacuum ports can assist in separating the membrane 15 from control surface 148, thereby allowing cassette 24 to more easily separate from control surface 148 and allowing door 141 to open freely. Pneumatic valves in the cycler can be controlled by automation computer 300 to provide positive pressure to vacuum ports 1483. Manifold 172 may separately include a dedicated valve channel for this purpose, or alternatively may employ the configurations and valves of the existing channel, operated in a particular sequence.
In one example, vacuum ports 1483 can be supplied with positive pressure by temporarily connecting vacuum ports 1483 to positive pressure tank 2620. Vacuum ports 1483 are normally connected to vacuum tank 2610 via a common fluid collection chamber. o Fluid Trap 1722 in manifold 172 during therapy. In one example, the controller or automation computer can open valve X1B between positive pressure reservoir and volume control chamber 171B and valve X1A between negative pressure reservoir and volume control chamber 171B simultaneously , which will pressurize the air in Fluid Trap 1722 and vacuum ports 1483. Pressurized air will flow through vacuum ports 1483 and between
184 membrane 15 and control surface 148, breaking any vacuum bond between the membrane and the control surface. However, in the illustrated manifold, the separator element 1491 of the cap separator 149 can be extended while supplying the positive pressure to the fluid in the common fluid collection chamber 1722, because the separator bladder 2630 is connected to the supply line. vacuum supply 2612. In this example, in a subsequent step, the 1722 fluid trap may be valveless from the now pressurized vacuum line and the two valves X1A, X1B connecting the positive and vacuum tanks to the volume control chamber 171B may be closed. Vacuum pump 2600 is then operated to reduce the pressure in vacuum reservoir 2610 and vacuum supply line 2612, which in turn allows separator element 1491 to be removed. Door 141 can then be opened after detaching cassette 24 from control surface 148 and retracting spacer element 1491.
In accordance with one aspect of the invention, vacuum ports 1483 can be used to detect leaks in membrane 15, for example, a liquid detector in a conduit or chamber connected to a vacuum port 1483 can detect liquid if the membrane 15 is perforated or the liquid is otherwise introduced between the membrane 15 and the control surface 148. For example, vacuum ports 1483 can be aligned with and hermetically associated with complementary vacuum ports 173B in matching block 170, which in turn can be hermetically associated with fluid passages 1721 leading to a chamber.
185 fluid collection common 1722 in manifold 172. Fluid collection chamber 1722 may contain an inlet through which a vacuum can be applied and distributed to all vacuum ports 1483 of control surface 148. By applying vacuum to fluid collection chamber 1722, fluid can be removed from each of vacuum ports 173B and 1483, thereby removing fluid from any space between membrane 15 and control surface 148 in the various regions of control. However, if liquid is present in one or more of the regions, the associated vacuum port 1483 can conduct the liquid in the vacuum ports 173B and on lines 1721 leading to the fluid collection chamber 1722. Any such liquid can be collected in fluid collection chamber 1722, and detected by one or more suitable detectors, for example, a pair of conductivity detectors that detect a change in conductivity in chamber 1722 indicating the presence of liquid. . In this embodiment, the detectors can be located on a lower side of the 1722 fluid collection chamber, while a vacuum source connects to the 1722 chamber at an upper end of the 1722 chamber. Therefore, if the liquid is led to the fluid collection chamber 1722, the liquid can be detected before the liquid level reaches the vacuum source. Optionally, a hydrophobic filter, valve, or other component can be placed at the point of connection of the vacuum source to chamber 1722 to help further resist the ingress of liquid into the vacuum source. In this way, a liquid leak can be detected and the
186 Controller 16 can take action on it (eg, generating an alert, closing liquid inlet valves, and ceasing pumping operations) before the vacuum source valve puts itself at risk of being contaminated by the liquid.
In one embodiment, the interior wall of the control chambers 171B may include raised elements that are somewhat analogous to the spacer elements 50 of the pump chamber, for example, as shown in Figure 37 for the control chambers 171B associated with the 1482 pump control regions. These elevated elements can take the form of plateau features, ribs, or other projections that keep the control ports depressed away from the fully retracted control regions 1482. This arrangement can allow for a more even distribution of pressure or vacuum in control chamber 171B, and prevent premature blocking of any control port by means of control surface 148. A preformed control surface 148 (at least in the pump control regions) may not be under significant stretching force when fully extended against either the inner wall of the cassette pump chamber 24 during a supply blow, or the interior wall of the control chamber 171 during a fill blow. Therefore, it may be possible for control region 1482 to spread asymmetrically in control chamber 171B, causing control region 1482 to prematurely close one or more control chamber ports before the chamber is evacuated.
187 completely. Having features on the interior surface of the control chamber 171B that prevent contact between the control region 1482 and the control ports can help to ensure that the control region 1482 can make uniform contact with the interior wall of the control chamber. control during a fill stroke.
As suggested above, cycler 14 may include a control system 16 with a data processor in electrical communication with the various valves, pressure detectors, motors, etc., of the system and is preferably configured to control such components in accordance with a desired sequence or protocol of operation. Control system 16 may include circuits, programming, computer memory, electrical connections, and / or other appropriate components to perform a specified task. The system may include pumps, tanks, manifolds, valves, or other components to generate desired air or other fluid pressure (either positive pressure - above atmospheric pressure or some other reference - or negative pressure or vacuum - below pressure). atmospheric or some other reference) to control the operation of the control surface regions 148, and other pneumatically operated components. Additional details regarding control system 16 (or at least portions thereof) are provided below.
In an illustrative embodiment, the pressure in the pump control chambers 171B can be controlled by means of a binary valve, for example, which opens to expose the control chamber 171 to a
188 suitable pressure / vacuum and closes to cut off the pressure / vacuum source. The binary valve can be controlled using a tooth-shaped saw control signal that can be modulated to control the pressure in the pump control chamber 171B. For example, during a pump supply stroke (i.e., where positive pressure is introduced into pump control chamber 171B to move membrane 15 / control surface 148 and force liquid out of the pump chamber 181), the binary valve can be driven by the sawtooth signal to open and close at a relatively fast speed to establish adequate pressure in the control chamber 171B (for example, a pressure between approximately 70-90 mmHg). If the pressure in the control chamber 171B rises above approximately 90 mmHg, the sawtooth signal can be adjusted to close the binary valve for a longer period. If the pressure drops below about 70mmHg in the control chamber, the sawtooth control signal can be applied again to the binary valve to raise the pressure in the control chamber 171. Therefore, during a typical pump operation, the binary valve will open and close multiple times, and can be closed for one or more prolonged periods, so that the pressure at which the liquid is forced from the pump chamber 181 it is maintained at a desired level or range (eg, approximately 7090 mmHg).
In some embodiments and in accordance with one aspect of the invention, it may be useful to detect an end of membrane strike 15 / region
189 pump control 1482, for example, when the membrane 15 contacts the spacers 50 in the pump chamber 181 or the pump control region 1482 contacts the wall of the pump control chamber 171B. For example, during a pumping operation, detection of the end of stroke may indicate that movement of the membrane 15 / pump control region 1482 must be reversed to start a new pump cycle (to fill pump chamber 181 or propel fluid from pump chamber 181). In an illustrative embodiment in which the pressure in control chamber 171B for a pump is controlled by means of a binary valve driven by a sawtooth control signal, the pressure in chamber 181 will fluctuate at a relatively high frequency, for example, a frequency at or near the frequency at which the binary valve opens and closes. A pressure detector in the control chamber 171B can detect this fluctuation, which generally has a higher amplitude when the membrane 15 / pump control region 1482 is not in contact with the inner wall of the pump chamber 181 or the 171B pump control chamber wall. However, once the membrane 15 / pump control region 1482 makes contact with the interior wall of the pump chamber 181 or with the wall of the pump control chamber 171B (i.e. the end of stroke), the pressure fluctuation is generally damped or otherwise changed in a way that is detectable by means of the pressure detector in the pump control chamber 171B. This change in pressure fluctuation can be used to identify the end of the stroke, and the
190 pump and other components of cassette 24 and / or cycler 14 can be controlled accordingly.
In one embodiment, the pneumatic pressure applied to the control chamber 171B is actively controlled by a processor that receives a signal from the pressure transducer 2672 (Figure 37C) connected to the control chamber 171B and a fast acting binary valve X1A , X1B between a pressure tank 2620, 2610 and the control chamber 171B. The processor can control the pressure with a variety of control algorithms including proportional closed loop or proportional integrator feedback that varies the valve duty cycle to achieve the desired pressure in the 171B control volume. In one embodiment, the processor controls the pressure in the control chamber with an on-off controller called the blast-blast controller. The on-off controller monitors the pressure in the control volume 171B during a supply blow and opens the binary valve X1B (which connects the control volume 171B with the positive reservoir 2620) when the pressure is less than a first lower limit and closes the binary valve X1B when the pressure is above a second upper limit. During a fill stroke, the on-off controller opens the binary valve X1A (which connects control volume 171B with negative reservoir 2610) when the pressure is greater than a third limit and closes the binary valve X1A when the pressure is less than a fourth limit, where the fourth limit is less than the third limit and both the third and fourth limits are
191 below the first limit. A graph of the pressure with the passage of time as during a supply stroke and the subsequent FMS measurement is shown in Figure 66. The control chamber pressure 2300 ranges from the first lower limit 2312 to the second upper limit 2310 while membrane 15 moves through control chamber 171B. The pressure stops oscillating between the limits when the membrane 15 stops moving. The membrane 15 typically stops moving when it contacts either the stage 50 rungs of the cassette or contacts the surface of the control chamber 171B. The membrane 15 can also be stopped moving if the outlet fluid line is occluded.
Automation computer 300 detects the end of stroke by evaluating the pressure signals. There are many possible algorithms to detect the end of pressure swing that indicate end-of-stroke (EOS). The algorithms and methods for detecting EOS in the section called Detailed Description of the System and Method of Measuring the Fluid Flow Rate of Change in US Pat. 6,520,747 and the section describing the filtration to detect the end of stroke at 8,292,594 are incorporated herein by reference.
In an example of an algorithm to detect EOS, the AC 300 evaluates the time between the pressure that crosses the first and second limits during a supply blow or the third and fourth limits during a fill blow. On-off controller opens and closes valves X1A, X1B in response to pressure ranging between the two limits while
192 that the volume of the control chamber changes during the filling or dispensing blow. When the membrane 15 stops moving at the end-of-stroke, the pressure changes will decrease significantly so that the pressure no longer exceeds one or both limits. The AC 300 can detect EOS by measuring the time between pressure that exceeds alternating limits. If the time since the pressure crosses the last limit exceeds a predefined threshold, then the AC 300 can declare an EOS. The algorithm may further include an initial period during which the AC 300 does not measure the time between the border crossings.
In another example algorithm, the AC 300 evaluates the derivative of the pressure signal with respect to time. The AC 300 can declare an EOS if the derivative remains below a minimum threshold for a minimum length of time. In a further example, the minimum threshold is the average of the absolute value of the average pressure derivative during the stroke. The algorithm calculates the hit (derived with respect to time) of a fit curve to a set of data points, where the data points are taken from a moving window. The absolute value of each slope is then averaged over the stroke to calculate the absolute value of the average pressure derivative. In another example of an EOS algorithm, the AC 300 may not include the pressure data until after an initial delay. The AC 300 ignores the initial pressure data to avoid false EOS detections due to irregular pressure traces that occasionally occur during the early part of the blow. In another example, the AC 300
193 declares an EOS only after the second derivative of pressure in the late part of the coup has remained below a threshold for a minimum time and a time-out period has passed.
The criteria for declaring an EOS can be optimized for different pumping conditions. Optimized EOS detection conditions include the second pressure derivative threshold, the minimum time to stay below the second derivative threshold, the length of the initial delay, and a length of the waiting period. These EOS detection criteria can be optimized differently, for example, the filling stroke of the bags 20, 22, the supply stroke to the patient, the filling stroke from the patient and the supply stroke to the bags 20 , 22. Alternatively, the EOS detection criteria may be a function of the pumping pressure in the control chamber 171B.
Occluder
In one aspect of the invention, an occluder to open / close one or more flexible lines may include a pair of opposing occlusion members, which may be configured as elastic elements, such as flat plates made of spring steel (eg, springs blade), which have a force actuator configured to apply a force to one or both of the occlusion members to operate the occluder. In certain embodiments, the force actuator may comprise an expandable or expandable member positioned between the members.
194 elastic. With the expandable member in a reduced size condition, the elastic members may be in a flat or near flat condition and drive a clamp head to engage one or more lines to tighten closed lines. However, when the expandable member drives the elastic elements apart, the elastic elements can bend and withdraw the clamp head, releasing the lines and allowing flow through the lines. In other embodiments, the occlusion members can be essentially rigid with respect to the force levels applied by the force actuator. In certain embodiments, the force actuator can apply a force to one or both opposing occlusion members to increase the distance between the occlusion members in at least a portion of the region where they are opposed to effect opening or closing of the tube. flexible.
Figure 38 shows an exploded view and Figure 39 shows a partially assembled view of an illustrative embodiment of an occluder 147 that can be used to close, or occlude, the patient and drain lines 34 and 28, and / or other lines. on cycler 14 or assembly 12 (such as, for example, heater bag line 26). The occluder 147 includes an optional clamp head 161, for example, a generally flat blade-shaped element that contacts the tubes to press the tubes against the door 141 and tighten the closed tubes. In other embodiments, the function of the clamp head could be replaced by an extension edge of one or both of the occlusion members 165. The head of
195 caliper 161 includes a gasket 162, such as an O-ring or other member, that cooperates with caliper head 161 to help resist the ingress of fluid (air or liquid for example) into the housing of cycler 14, for example, in the event of a leak in one of the occluded lines. The bellows gasket 162 is mounted on, and the caliper head 161 passes through, a caliper head guide 163 that is mounted to the front panel of the cycler housing, i.e., the panel exposed when opening door 141. The clamp head guide 163 allows the clamp head 161 to move in and out of the clamp head guide 163 without bonding and / or substantial resistance to sliding movement of the clamp head 161. A pivot shaft 164 is attached to a pair of opposing occluder members, comprising in the illustrated embodiment spring plates 165, each of which includes a hook-shaped pivot shaft bearing, for example, as found on standard door hinges, at clamp head 161. That is, the openings of the arrow guides in the clamp head 161, and the openings formed by the hook-shaped bearings in the spring plates 165 are aligned with each other and the pivot arrow 164 is inserted through the openings whereby the clamp head 161 and spring plates 165 are pivotally connected to each other. The spring plates 165 can be made of any suitable material, such as steel, and can be arranged to be generally flat when not under stress. The opposite end of the spring plates 165 includes similar hook-shaped bearings, which
196 they are pivotally connected to a linear adjuster 167 by a second pivot shaft 164. In this embodiment, the force actuator comprises a bladder 166 that is positioned between spring plates 165 and arranged so that when fluid (eg, air under pressure) is introduced into the bladder, the bladder can expand and push spring plates 165 away from each other in a region between pivot axes 164. The bladder 166 can be attached to one or both of the spring plates 165 by means of pressure sensitive adhesive tape (PSA). A linear adjuster 167 is attached to the housing of the cycler 82 while the clamp head 161 is allowed to float, although its movement is guided by the clamp head guide 163. The linear adjuster 167 includes slot holes at its lower end, allowing the entire assembly to be adjusted in position and thus allowing the clamp head to be properly positioned when the occluder 147 is installed in the cycler 14. A quencher 168 or other arrangement it can be used to help adjust the position of the linear adjuster 167 relative to the housing 82. That is, the clamp head 161 generally needs to be properly positioned whereby with the spring plates 165 positioned close to each other and the bladder 166 substantially emptied or at ambient pressure, the clamp head 161 is properly depressed over the patient's lines. and drained to tighten closed tubes to flow without cutting, twisting, or otherwise damaging tubes. The slot openings in linear adjuster 167 allow this fine placement and locking of occluder 147 in place. An overlapping release device, such as that provided by the
197 release blade 169 is optionally located between the spring plates 165 and as described in more detail below, it can be rotated to push the spring plates 165 apart, thus withdrawing the clamp head 161 towards the clamp head guide 163. Release blade 169 can be manually operated, for example, to disable occluder 147 in the event of power loss, bladder failure 166, or other circumstance.
Additional configurations and descriptions of certain components that may be instructive in the construction of certain modalities of the occluder are provided in US Patent No. 6,302,653. Spring plates 165 can be constructed of any material that is elastically resistant to bending forces and that has sufficient longitudinal stiffness (bending resistance) to provide sufficient restoring force, in response to bending displacement, to occlude a desired number of crushable tubes. In the illustrated embodiment, each spring plate is essentially flat when not under tension and in the form of a sheet or plate. In alternative modalities utilizing one or more elastic occlusion members (spring members), any occlusion member (s) that is elastically resistant to bending forces and that has sufficient longitudinal stiffness (resistance to bending) to provide restoring force Sufficient in response to a bending displacement to occlude a desired number of collapsible tubes can be used. Potentially suitable spring members may have a
198 wide variety of shapes as is apparent to those skilled in the art including, but not limited to, cylindrical, prism, trapezoidal, square or rectangular beams or beams, I-beams, elliptical beams, bowl-shaped surfaces and others. Those of skill in the art can easily select appropriate materials and dimensions for spring plates 165 based on the present teachings and the requirements of a particular application.
FIG. 40 shows a top view of the occluder 147 with the bladder 166 deflated and the spring plates 165 positioned close to each other and in a flat or nearly flat condition. In this position, the clamp head 161 is fully extended from a clamp head guide and the front panel of the cycler 14 (i.e., the panel within the door 141) and enabled to occlude the patient and drain lines. Figure 41, on the other hand, shows the bladder 166 in an inflated state in which the spring plates 165 are pushed apart, thereby retracting the clamp head 161 towards the clamp head guide 163. (Note that the adjuster Line 167 is fixed in place relative to cycler housing 82 and thus fixed relative to front panel of housing 82. As the spring plates 165 move apart, the caliper head 161 moves back relative to the front panel as the caliper head 161 is arranged to move freely in and out of the head guide clamp 163). This condition prevents the clamp head 161 from occluding the patient and drain lines and is the
199 condition in which occluder 147 remains during normal operation of cycler 14. That is, as described above, various components of cycler 14 can operate using air / vacuum pressure, eg, control surface 148 can operate under impulse pressure / air pressure to cause fluid pumping and valve operation for cassette 24. Therefore, when cycler 14 is operating normally, cycler 14 can produce enough air pressure to not only control system operation, but also to inflate bladder 166 to retract clamp head 161 and prevent line occlusion. patient and drain. However, in the event of a system shutdown, fault, defect, or other condition, the air pressure of the bladder 166 can be determined, causing the bladder 166 to deflate and the spring plates 165 to stiffen and extend the head of clamp 161 to occlude the lines. A possible advantage of the arrangement shown is that the return force of the spring plates 165 is balanced in such a way that the caliper head 161 will generally not be attached to the caliper head guide 163 when it moves relative to the guide caliper head 163. In addition, opposing forces on spring plates 165 will tend to reduce the amount of asymmetric friction wear of the pivot shafts and bushings in the assembly. Also, once the spring plates 165 are in an approximately straight position, the spring plates 165 can exert a force in a direction that is generally along the length of the clip head 161 that is several times larger than the force exerted by the bladder 166 on the plates
200 spring 165 to separate spring plates 165 from each other and retract clamp head 161. Furthermore, with the spring plates 165 in a flat or nearly flat condition, the force required to be exerted by the fluid on the crushed tube to overcome the clamp force exerted by the clamp head 161 reaches a relatively high required force, when applied to the spring plates at their ends and essentially parallel to the plane of the flattened spring plates, to buckle the spring plates when breaking the column stability of the flattened spring plates. As a result, occluder 147 can be very effective in occluding lines with a reduced probability of failure while also requiring a relatively small force to be applied by bladder 166 to retract clamp head 161. The dual spring plate arrangement of the illustrative embodiment may have the additional advantage of significantly increasing the clamp force provided by the clamp head, for any given force required to bend the spring plate and / or for any given size and thickness of the spring plate.
In some circumstances, the force of the occluder 147 on the lines can be relatively large and can cause the door 141 to be difficult to open. That is, the door 141 must oppose the force of the occluder 147 when the clamp head 161 is in contact with and occludes the lines, and in some cases this may cause the latch that keeps the door 141 in a closed state to be difficult. or impossible to operate manually. Of course, if cycler 14 is started and produces air pressure to
201 operate, the bladder of the occluder 166 can be inflated and the clamp head of the occluder 161 can be retracted. However, in some cases, such as with a pump failure in cycler 14, inflation of the bladder 166 may be impossible or difficult. To allow door opening, occluder 147 may include a manual release. In this illustrative embodiment, occluder 147 may include a release blade 169 as shown in Figures 38 and 39 that includes a pair of wings pivotally mounted for rotary movement between spring plates 165. When at rest, the wings of the release blade can be aligned with the springs as shown in Figure 39, allowing the occluder to operate normally. However, if the spring plates 165 are in a flat condition and the caliper head 161 needs to be manually retracted, the release blade 169 may be rotated, for example, by engaging a hex wrench or other tool with the release blade. 169 and rotate release blade 169 so that the wings push spring plates 165 apart. The hex wrench or other tool may be inserted through an opening in cycler housing 14, for example, an opening near the left-hand handle depression in cycler housing 82 and operated to disengage occluder 147 and let door 141 open.
202
Pump Volume Supply Measurement
In another aspect of the invention, cycler 14 can determine a volume of fluid delivered to various lines of system 10 without the use of a flow meter, scale, or other direct measurement of fluid volume or weight. For example, in one embodiment, a volume of fluid moved by a pump, such as a pump in cassette 24, can be determined based on pressure measurements of a gas used to drive the pump. In one embodiment, a volume determination can be made by isolating two chambers from each other, measuring the respective pressures in the isolated chambers, allowing the pressures in the chambers to be partially or substantially equalized (by fluid connection of the two chambers) and measuring the pressures. Using the measured pressures, the known volume of one of the chambers, and an assumption that equalization occurs in an adiabatic form, the volume of the other chamber (eg, a pump chamber) can be calculated. In one embodiment, the pressures measured after the chambers are fluidly connected may be substantially unequal to each other, that is, the pressures in the chambers may not have been fully equalized. However, these substantially uneven pressures can be used to determine a volume of the pump control chamber, as explained below.
For example, Figure 42 shows a schematic view of a pump chamber 181 of cassette 24 and associated control components and inflow / outflow paths. In this illustrative example, a
203 Liquid supply, which may include heater bag 22, heater bag line 26, and a flow path through cassette 24, is shown providing a liquid inlet into the upper opening 191 of the pump chamber. The liquid outlet is shown in this example as receiving liquid from the lower opening 187 of the pump chamber 181, and may include a flow path of the cassette 24 and the patient line 34, for example. The liquid supply can include a valve, eg, including valve port 192, which can be opened and closed to allow / prevent flow to or from pump chamber 181. Similarly, the liquid outlet can include a valve, for example, including valve port 190, which may be open and closed to allow / impede flow to or from pump chamber 181. Of course, the liquid supply could include any suitable arrangement, such as one or more solution containers, the patient line, one or more flow paths in the cassette 24 or other liquid source, and the liquid outlet could also include any suitable arrangement such as a drain line, the heater bag and the heater bag line, one or more flow paths in the cassette 24 or other liquid outlet. Generally speaking, the pump chamber 181 (ie, on the left side of the membrane 14 in Figure 42) will be filled with a non-compressible liquid, such as water or dialysate, during operation. However, air or other gas may be present in pump chamber 181 in some circumstances, such as during initial operation, initiation, or other
204 situations as described below. Also, it should be understood that although aspects of the invention related to volume and / or pressure detection for pump are described with reference to the pump arrangement of cassette 24, aspects of the invention can be used with any suitable pump or pump motion system. fluid.
Figure 42 also schematically shows to the right of the membrane 15 and the control surface 1482 (which are adjacent to each other) a control chamber 171B, which can be formed as a vacuum or other space in the pairing block 170A associated with pump control region 1482 of control surface 1482 for pump chamber 181, as discussed above. It is in the control chamber 171B where the appropriate air pressure is introduced to cause the membrane 15 / control region 1482 to move and pump liquid into the pump chamber 181. The control chamber 171B can communicate with a line LO branching off to another line L1 and a first valve X1 communicating with a pressure source 84 (eg, an air or vacuum pressure source). Pressure source 84 may include a piston pump in which the position is moved in a chamber to control a pressure supplied to control chamber 171B, or may include a different type of pressure pump and / or tank (s) to supply adequate gas pressure to move the membrane 15 / control region 1482 and perform the pumping action. Line LO also leads to a second valve X2 that communicates with another line L2 and a reference chamber 174 (for
205 example, a space properly configured to perform the measurements described above). Reference chamber 174 also communicates with a line L3 having a valve X3 leading to a vent or other reference pressure (eg, a source of atmospheric pressure or other reference pressure). Each of the X1, X2 and X3 valves can be independently controlled. Pressure detectors can be arranged, for example, a detector like control chamber 171B and another detector in reference chamber 174, to measure the pressure associated with the control chamber and the reference chamber. These pressure detectors can be located and can operate to detect pressure in a suitable way. The pressure detectors can communicate with the control system 16 for the cycler 14 or another suitable processor to determine a volume supplied by the pump or other characteristics.
As mentioned before, the valves and other components of the pump system shown in Figure 42 can be controlled to measure pressures in pump chamber 181, the liquid supply and / or liquid outlet, and / or to measure a volume of fluid supplied from pump chamber 181 to the liquid supply or liquid outlet. Regarding volume measurement, one technique used to determine a volume of fluid supplied from pump chamber 181 is to compare the relative pressures in control chamber 171B with those of reference chamber 174 in two pump states. different. By comparing relative pressures a change in volume can be determined in the
206 control chamber 171B, which corresponds to the change in volume in pump chamber 181 and reflects a volume supplied from / received in pump chamber 181. For example, after the pressure in control chamber 171B is reduced during a pump chamber fill cycle (for example, applying negative pressure from the pressure source through valve X1 open) to put membrane 15 and the pump control region 1482 in contact with at least a portion of the wall of the control chamber (or in another suitable position for the membrane 15 / region 1482), valve X1 can be closed to isolate the control chamber from the pressure source, and valve X2 can be closed, thus isolating reference chamber 174 from control chamber 171B. Valve X3 may be open to ventilate the reference chamber at ambient pressure, then closed to isolate the reference chamber. With valve X1 closed and pressures in the control chamber and reference chamber measured, valve X2 is then opened to allow the pressure in the control chamber and reference chamber to equalize. The initial reference chamber and control chamber pressures, along with the known reference chamber volume and measured pressures after equalization has started (but not necessarily yet completed) can be used to determine a volume for the control chamber. This process can be repeated at the end of the pump supply cycle when the sheet 15 / control region 1482 is pushed into contact with the separator elements 50 of the pump chamber 181. By comparing the volume of the control chamber at the end of the cycle of
207 filled with the volume at the end of the supply cycle, a volume of liquid supplied from the pump can be determined.
Conceptually, the pressure equalization process (for example, at the valve opening X2) is seen as happening in an adiabatic way, that is, without heat transfer occurring between the air in the control and reference chambers and its environment. The conceptual notion is that there is an imaginary piston initially located in valve X2 when valve X2 is closed, and that the imaginary piston moves in line LO or L2 when valve X2 is open to equalize the pressure in the control chambers. and reference. Since (a) the pressure equalization process happens relatively quickly, (b) the air in the control chamber and the reference chamber have approximately the same element concentrations, and (c) the temperatures are similar, the assumption of that pressure equalization occurs adiabatically can introduce only a small error in volume measurements. Also, in one embodiment, the pressures taken after equalization have been initiated and can be measured before substantial equalization has occurred - thus reducing the time between the measurement of the initial pressures and the final pressures used to determine the volume of the pump chamber. Error can be further reduced, for example, using low thermal conductivity materials for membrane 15 / control surface 1482, cassette 24, control chamber 171B, lines, reference chamber 174, etc., to reduce heat transfer.
208
Given the assumption that an adiabatic system exists between the state when valve X2 is closed until after valve X2 is open and pressure is equalized, the following applies:
PV<sup>1</sup> = Constant (1) where P is pressure, V is volume, and γ is equal to a constant (for example, about 1.4, where gas is diatomic, like air). Therefore, the following equation can be written to relate the pressures and volumes in the control chamber and the reference chamber before and after valve opening X2 and pressure equalization occurs:
PrVr<sup>AND</sup> + PoE<sup>AND</sup> = Constant = PfVf (2) where Pr is the pressure in the reference chamber and lines L2 and L3 before the opening of valve X2, Vr is the volume of the reference chamber and lines L2 and L3 before the opening of valve X2, Pd is the pressure in the control chamber and lines LO and L1 before the opening of valve X2, Vd is the volume of the control chamber and lines LO and L1 before opening valve X2, Pf is the equalized pressure in the reference chamber and control chamber after valve opening X2, and Vf is the volume of the entire system including the control chamber, reference chamber, and lines LO, L1, L2 , and L3, that is, Vf = Vd + Vr. Because Pr, Vr, Pd, Pf, and γ are known, and Vf = Vr + Vd, this equation can be used to solve Vd. (Although referenced here, including in
209 The claims, for the use of a "measured pressure" in the determination of volume values, etc., it should be understood that said measured pressure value is not necessarily some particular form, such as in units of kg / cm<sup>2</sup>. Rather, a measured pressure or a determined pressure can include any value that is representative of a pressure, such as a voltage level, a resistance value, a digital multibit number, etc. For example, a pressure transducer used to measure pressure in the pump control chamber may give an analog voltage level, resistance, or other indication that is representative of the pressure in the pump control chamber. The empirical output of the transducer can be used as a measured pressure and / or some modified form of the output, such as a digital number generated using an analog output of the transducer, kg / cm<sup>2</sup>, or another value that is generated based on the output of the transducer, etc. The same is true of other values, such as a given volume, which is not necessarily in a particular shape such as cubic centimeters. Rather, a given value can include any value that is representative of the volume, for example, it could be used to generate an actual volume in, i.e., cubic centimeters.
In one embodiment of a fluid management system (FMS) technique for determining a volume delivered by the pump, pressure equalization with valve opening X2 is assumed to occur in an adiabatic system. Therefore, equation 3 below gives the relationship of
210 Reference chamber system volume before and after pressure equalization:
Vrf = Vri (Pf / Patm) "<sup>(1 / y)</sup> (3) where Vrf is the final (post-equalization) volume of the reference chamber system including the volume of the reference chamber, the volume of lines L2 and L3, and the volume adjustment resulting from piston movement , which can be moved to the left or right of valve X2 after opening, Vri is the initial volume (pre-equalization) of the reference chamber and lines L2 and L3 with the piston located in valve X2, Pf is the final equalized pressure after valve X2 is opened, and Patm is the initial reference chamber pressure before valve X2 opens (in this example, atmospheric pressure). Similarly, Equation 4 gives the ratio of the volume of the control chamber system before and after pressure equalization:
Vdf = Vdi (Pf / Pdi) "<sup>(1 / Y)</sup> (4) where Vdf is the final volume of the control chamber system including the volume of the control chamber, the volume of the LO and L1 lines, and the volume adjustment resulting from piston movement, which can be move left or right of valve X2 after opening, Vdi is the initial volume of the control chamber and lines LO and L1 with the piston located in valve X2, Pf is the final pressure after the valve X2 is open, and Pdi is the initial pressure of the control chamber before the opening of valve X2.
211
The volumes of the reference chamber system and the control chamber system will change by the same absolute amount after the X2 valve opens and the pressure equals, but will differ in sign (for example, because the change in volume is caused by movement of the piston to the left or to the right when valve X2 opens), as shown in equation 5:
AVr = (-1) AVd (5) (Note that this change in volume for the reference chamber and the control chamber is only due to the movement of the imaginary piston. The reference chamber and the control chamber will not actually change in volume during the equalization process under normal conditions). Also, using the relation in equation 3, the change in volume of the reference chamber system is given by:
AVr = Vrf - Vri = Vri (-1 + (Pf / Patm)<sup>Η1 / γ)</sup>) (6)
Similarly, using Equation 4, the change in volume of the control chamber system is given by;
AVd = Vdf - Vdi = Vdi (-1 + (Pf / Pdi) '<sup>(1 / γ)</sup>) (7)
Because Vri is known, since Pf and Patm are measured or known, Ase can calculate Vr, which according to Equation 5 is assumed to be equal to (-) AVd. Therefore, Vdi (the volume of the control chamber system before pressure equalization with the reference chamber) can be calculated using Equation 7. In this mode, Vdi represents the
212 control chamber volume plus LO and L1 lines, of which LO and L1 are fixed and known quantities. Subtracting LO and L1 from Vdi produces the volume of the control chamber alone. Using equation 7 above, for example, both before (Vdi1) and after (Vd¡2) of a pump operation (for example, at the end of the fill cycle and at the end of the discharge cycle), the change in volume The control chamber can be determined, thus providing a measurement of the volume of fluid supplied by (or taken up by) the pump. For example, if Vdi 1 is the volume of the control chamber at the end of the fill stroke, and Vd¡2 is the volume of the control chamber at the end of the subsequent supply stroke, the volume of fluid delivered by the pump is You can estimate by subtracting Vd¡1 from Vd¡2. Since this measurement is made based on pressure, the determination of volume can be made for almost any position of the membrane 15 / pump control region 1482 in pump chamber 181, either for a full pump stroke or partial. However, measurement made at the end of fill and supply strokes can be accomplished with little or no impact on pump operation and / or flow velocity.
One aspect of the invention involves a technique for identifying pressure determination values to be used in determining a volume for the control chamber and / or other purposes. For example, although pressure detectors can be used to detect a pressure in the control chamber and a pressure in the reference chamber, the detected pressure values may vary with the opening / closing of the valves, the
213 introduction of pressure into the control chamber, ventilation of the reference chamber to atmospheric pressure or other reference pressure, etc. Also, because in one embodiment it is assumed that an adiabatic system exists from a time before pressure equalization between the control chamber and reference chamber until after equalization, identifying appropriate pressure values that were closely measured Over time it can help reduce error (for example, because a shorter elapsed time between pressure measurements can reduce the amount of heat exchanged in the system). Therefore, the measured pressure values may need to be chosen carefully to help ensure that the appropriate pressures are used to determine a volume delivered by the pump, etc.
For purposes of explanation, Figure 43 shows a graph of illustrative pressure values for the control chamber and reference chamber from a point in time before valve X2 opens to some time after valve X2 is open to allow pressure in chambers to equalize. In this illustrative embodiment, the pressure in the control chamber is higher than the pressure in the reference chamber before equalization, but it should be understood that the pressure in the control chamber may be lower than the pressure in the chamber reference before equalization in some arrangements, such as during and / or at the end of a fill stroke. Also the graph in Figure 43 shows a horizontal line marking the equalization pressure but it should be understood that this
214 line is displayed for clarity only. The equalizing pressure in general will not be known prior to valve X2 opening. In this mode, pressure detectors detect pressure at a rate of approximately 200Hz for both the control chamber and the reference chamber, although adequate sampling rates could be used. Before the valve X2 opens, the pressures in the control chamber and the reference chamber are approximately constant, with no air or other fluid being introduced into the chambers. Therefore, valves X1 and X3 will generally be closed at one time before valve X2 opens. Also, the valves leading to the pump chamber, such as valve ports 190 and 192, may be closed to prevent influence of pressure variations in the pump chamber, liquid supply, or liquid outlet.
First, the measured pressure data is processed to identify the initial pressures for the control chamber and the reference chambers, ie, Pd and Pr. In an illustrative embodiment, the initial pressures are identified based on analysis of a 10 point sliding window used on measured pressure data. This analysis involves generating a better fit line for the data in each window (or set), v, .gr., Using a least squares technique, and determining a slope for the best fit line. For example, each time a new pressure is measured for the control chamber or the reference chamber, a least squares adjustment line can be determined for a
215 Data set that includes the last measurement and the 9 previous pressure measurements. This process can be repeated for various pressure data sets, and a determination can be made as to when the slope of the least squares fit lines first becomes negative (or otherwise non-zero) and continues to grow further. negative for subsequent data sets (or otherwise deviates from a zero slope). The point at which the least squares adjustment lines start to have an adequate non-zero slope and in increments can be used to identify the initial pressure of the chambers, i.e. at a time before valve X2 opens .
In one embodiment, the initial pressure value for the reference chamber and the control chamber can be determined to be in the last of the 5 consecutive data sets, where the slope of the best fit line for the data sets is incremented from the first data set to the fifth data set, and the slope of the best fit line for the first data set first becomes non-zero (i.e. the slope of the best fit lines for data sets preceding the first data set is zero or otherwise not sufficiently different from zero). For example, the pressure detector can take samples every<sup>1</sup>Λ millisecond (or other sampling rate) that starts at a time before valve X2 opens. Each time a pressure measurement is made, the cycler 14 can take the most recent measurement along with the previous 9 measurements and generate a better line of adjustment at
216 data points in the set. When taking the next pressure measurement (for example,<sup>1</sup>/ 2 millisecond later), cycler 14 can take the measurement along with the previous 9 measurements, and again generate a better fit line at the 10 points in the set. This process can be repeated, and cycler 14 can determine when the slope of the best fit line for a set of 10 data points first becomes non-zero (or otherwise adequately inclined) and, for example, that the Slope of the best fit line for 5 subsequent sets of 10 data points increases with each subsequent data set. To identify the specific pressure measurement to be used, one technique is to select the third measurement in the 5<sup>t0</sup> dataset (i.e. 5<sup>t0 </sup>dataset with which the best fit line was found to have consistently increased on the slope and the 1<sup>was</sup> measurement is the pressure measurement that was taken at the earliest point in time) as the measurement to be used as the initial pressure for the control chamber or reference chamber, ie Pd or Pr. This selection was chosen using methods empirical, for example, by plotting the pressure measurement values and then selecting which point best represents the time when the pressure begins the equalization process. Of course, other techniques could be used to select the appropriate initial pressure.
In an illustrative embodiment, a check can be made that the times at which the selected Pd and Pr measurements occurred are within the desired time threshold, for example, within
217
1-2 milliseconds from each other. For example, if the technique described above is used to analyze the control chamber pressure and the reference chamber pressure and identify a pressure measurement (and therefore a point in time) just before the equalization of pressure, the times at which the pressures were measured should be relatively close to each other. Otherwise, there may be an error or other fault condition that invalidates one or both of the pressure measurements. By confirming that the time at which Pd and Pr occurred are adequately close, cycler 14 can confirm that the initial pressures were appropriately identified.
To identify when the pressures in the control chamber and the reference chamber have been equalized so that those measured chamber pressures can be used to reliably determine pump chamber volume, cycler 14 can analyze data sets including a series of data points from pressure measurements for both the control chamber and the reference chamber, determine a best fit line for each of the data sets (for example, using a least squares method) and identify when the slopes of the best fit lines for a set for the control chamber and a data set for the reference chamber are first adequately similar to each other, for example, the slopes are both close to zero or have values that are within a threshold of each other. When the slopes of the best fit lines are similar
218 or close to zero, the pressure can be determined to be equalized. The first pressure measurement value for any data set can be used as the final equalized pressure, ie Pf. In an illustrative embodiment, pressure equalization was found to generally occur within approximately 200-400 milliseconds after valve X2 opened, with the equalizing thickness occurring within approximately 50 milliseconds. Consequently, the pressure in the control and reference chambers can be sampled approximately 400 to 800 times or more during the entire equalization process from a time before valve X2 opens until a time when the equalization.
In some cases, it may be desirable to increase the accuracy of the control chamber volume measurement using an alternate FMS technique. Substantial differences in temperature between the liquid being pumped, the gas in the control chamber, and the gas in the reference chamber can introduce significant errors in calculations based on the assumption that pressure equalization occurs adiabatically. Waiting to make pressure measurements until complete pressure equalization between the control chamber and the reference chamber can allow an excessive amount of heat transfer to occur. In one aspect of the invention, the pressure values for the pump chamber and the reference chamber that are substantially equal to each other, i.e. measured before
219 After complete equalization has occurred, they can be used to determine the volume of the pump chamber.
In one embodiment, heat transfer can be minimized, and adiabatic calculation error can be reduced, by measuring chamber pressures throughout the equalization period from valve opening X2 through full pressure equalization , and selecting a sampling point during the equalization period during adiabatic calculations. In one embodiment of an APD system, the measured chamber pressures that are taken earlier to complete the pressure equalization between the control chamber and the reference chamber can be used to determine the volume of the pump chamber. In one embodiment, these pressure values can be measured approximately 50 ms after the chambers are first fluidly connected and equalization is initiated. As mentioned before, in one embodiment, full equalization can occur approximately 200-400ms after valve X2 opens. Therefore, the measured pressures can be taken at a point in time after valve X2 is opened (or equalization is started) ie approximately 10% to 50% or less of the total equalization period. Otherwise, the measured pressures can be taken at a point in time where 50-70% pressure equalization has occurred (i.e., the reference chamber and pump pressures have changed by approximately 50-70% of the difference between the initial chamber pressure and the final equalized pressure). Using a controller
220 Computer-enabled, a substantial number of pressure measurements in the control and reference chambers can be made, stored, and analyzed during the equalization period (eg, 40-100 individual pressure measurements). Among the time points sampled during the first 50 ms of the equalization period, there is a theoretically optimized sampling point to conduct adiabatic calculations (for example, see Figure 43 in which the optimized sampling point occurs at approximately 50 ms after valve X2 opens). The optimized sampling point can occur early enough after valve X2 opens to minimize heat transfer between the gas volumes of the two chambers, but not so early as to introduce significant errors in pressure measurements due to the properties of pressure detectors and delays in valve actuation. However, as seen in Figure 43, the pressures for the pump chamber and reference chambers may be substantially unequal to each other at that point, and therefore equalization may not be complete. (Note that in some cases, it may be technically difficult to take reliable pressure measurements immediately after the valve X2 is opened, for example, due to the inherent inaccuracies of the pressure detectors, the time required for the valve X2 to open completely and the rapid initial change in pressure from either the control chamber or the reference chamber immediately after valve X2 opens.)
221
During pressure equalization, when the final pressure for the control chamber and reference chambers is not the same, equation 2 becomes:
PriVri<sup>AND</sup> + Pd¡Vdi<sup>and</sup> = Constant = PrfVrf + PdfVdf (8) where: Pri = pressure in the reference chamber before opening of valve X2, Pdi = pressure in the control chamber before opening of valve X2, Prf = pressure of final reference chamber, Pdf = final control chamber pressure.
An optimization algorithm can be used to select a point in time during the pressure equalization period where the difference between the absolute values of AVd and AVr is minimized (or below a desired threshold) during the equalization period. . (In an adiabatic process, the difference should ideally be zero, as indicated by Equation 5. In Figure 43, the point in time at which the difference between the absolute values of AVd and AVr is minimized occurs on the 50 ms line, marked "time at which end pressures were identified.") First , the pressure data can be collected from the control and reference chambers as multiple points j = 1 across n between the valve opening X2 and the final pressure equalization. Since Vri, the set volume of the reference chamber system before pressure equalization is known, a subsequent value for Vrj (volume of the reference chamber system at sampling point j after valve X2 has opened) can be calculated using equation 3 in each
222 Sampling point Prj along the equalization curve. For each value of Vrj, a value for AVd can be calculated using Equations 5 and 7, each value of Vrj thus producing Vdij, a putative value for Vdi, the volume of the control chamber system prior to pressure equalization. Using each Vrj value and its corresponding Vdij value, and using Equations 3 and 4, the difference in the absolute values of AVd and AVr can be calculated at each pressure measurement point along the equalization curve. The sum of these square differences provides a measurement of the error in the calculated value of Vdi during pressure equalization for each value of Vrj and its corresponding Vdij. By denoting the pressure of the reference chamber that produces the smallest sum of the squared differences of | AVd | and | AVr | as Prf, and its associated reference chamber volume as Vrf, the Prf and Pdf data points that correspond to Vrf can then be used to calculate an optimized estimate of Vdi, the initial volume of the control chamber system.
One method of determining where on the equalization curve to capture an optimized value for Pdf and Prf is as follows:
1) Acquire a series of pressure data sets from the control and reference chambers starting immediately before valve X2 opens and ending with Pr and Pd becoming close to equal. If Pri is the first captured reference chamber pressure, then subsequent sampling points in Figure 32 will be mentioned as Prj = Pr1, Pr2, ... Prn.
223
2) Using equation 6, for each Prj after Pri, the corresponding AVrj is calculated where j represents the jth of pressure data after Pri.
AVrj = Vrj - Vri = Vri (-1 + (Prj / Pr¡) “<<sup>1 / γ)</sup>
3) For each of these AVrj calculate the corresponding Vdij using Equation 7. For example:
AVr1 = Vri * (-1 + (Pr1 / Pri) <sup>_ (1 / γ)</sup>)
AVd1 = -AVr1
Thus,
Vd¡1 = AVd1 / (-1 + (Pd1 / Pdi) <sup>_ (1 / γ)</sup>)
Vdin = AVdn / (-1 + (Pdn / Pdi) "<sup>(1 / Y)</sup>)
Having calculated a set of n initial control chamber system volumes (Vdi1 to Vdin) based on the set of reference chamber pressure data points Pr1 to Prn during pressure equalization, it is now possible to select the point at time (f) that produces an optimized measurement of the initial volume of the control chamber system (Vdi) over the entire pressure equalization period.
4) Using Equation 7, for each Vd¡1 through Vdin, calculate all AVdj, k using pressure measurements from the control chamber Pd for points in time k = 1 to n.
For the Vdi corresponding to Pr1:
224
AVd1,1 = Vd¡1 * (-1 + (Pd1 / Pdi) <sup>_ (1 / γ)</sup>)
AVd1,2 = Vd¡1 * (-1 + (Pd2 / Pdi) '<sup>(1 / γ)</sup>)
AVd1, n = Vd¡1 (-1 + (Pdn / Pdi) ~<sup>(1 / Y)</sup>)
For the Vdi corresponding to Prn:
AVdn, 1 = Vdin * (-1 + (Pd 1 / Pdi) ~<sup>(1 / γ)</sup>)
AVdn, 2 = Vdin * (-1 + (Pd2 / Pd¡)<sup>41 / γ</sup>>)
AVdn, n = Vdin * (-1 + (Pdn / Pdi)<sup>_ (1 / γ)</sup>)
5) Take the error of the sum of squares between the absolute values of AVr's and AVdj, k's n
If = Σ (| AV<sub>d1</sub>,<sub>k</sub>| - | AV<sub>rk</sub>|)<sup>2</sup> k = 1 [S1 represents the error of the sum of squares of | AVd | less | AVr | over all data points during the equalization period when
225 the first data point Pr1 is used to determine Vdi, the initial volume of the control chamber system, of Vr1 and AVr.] n
S<sub>2</sub> = Σ (| AV<sub>d2</sub>,<sub>k</sub>| - | AV<sub>rk</sub>|)<sup>2</sup> k = 1 [S2 represents the error of the sum of squares of | AVr | less | AVd | over all data points during the equalization period when the second data point Pr2 is used to determine Vdi, the initial volume of the control chamber system, of Vr2 and AVr.] n
S<sub>n</sub> = Σ (| AV<sub>dn</sub>,<sub>k</sub>| - | AV<sub>rk</sub>|)<sup>2</sup> k = 1
6) The data point of Pr ent Pr1 and Prn that generates the error of the minimum sum of squares S from step 5 (or a value that is below a desired threshold) then becomes the chosen Prf, of which Pdf and An optimized estimate of Vdi, the initial control chamber volume, can then be determined. In this example, Pdf occurs at, or approximately, the same time as Prf.
7) The above procedure can be applied any time an estimate of the control chamber volume is desired, but
226 it can preferably be applied at the end of each filling stroke and each supply stroke. The difference between the optimized Vdi at the end of a fill stroke and the optimized Vdi at the end of a corresponding supply stroke can be used to estimate the volume of liquid delivered by the pump.
Air detection
Another aspect of the invention involves determining an air presence in pump chamber 181, and if present, a volume of air present. Such a determination may be important, for example, to help ensure that an initiation sequence is properly performed to remove air from cassette 24 and / or to help ensure that air is not supplied to the patient. In certain embodiments, for example, when fluid is supplied to the patient through Lower opening 187 at the bottom of pump chamber 181, air or other gas that is trapped in the pump chamber may tend to remain in the pump chamber 181 and will be inhibited from being pumped into the patient unless the volume of the gas is greater than the effective dead space volume of the pump chamber 181. As described below, the volume of air or other gas contained in pump chambers 181 can be determined in accordance with aspects of the present invention, and gas can be purged from pump chamber 181 before the volume of gas be
227 greater than the effective dead space volume of pump chamber 181.
A determination of an amount of air in pump chamber 181 can be made at the end of a fill stroke, and therefore can be performed without interrupting a pumping process. For example, at the end of a fill stroke during which the membrane 15 and the pump control region 1482 are moved away from the cassette 24 such that the membrane 15 / region 1482 is brought into contact with the chamber wall. Control 171, valve X2 can be closed, and the reference chamber ventilated at atmospheric pressure, for example, by opening valve X3. Subsequently, valves X1 and X3 can be closed by fixing the imaginary "piston" on valve X2. Valve X2 can then be opened, allowing pressure equalization in the control chamber and in the reference chamber, as described above when taking pressure measurements to determine a volume for the control chamber.
If there is no air bubble in pump chamber 181, the change in volume of the reference chamber, that is, due to the movement of the imaginary "piston", determined using the known initial volume of the reference chamber system and the pressure Initial in the reference chamber will be equal to the change in volume of the control chamber determined using the known initial volume of the control chamber system and the initial pressure in the control chamber. (The initial volume of the control chamber can be known under conditions where the membrane
228
15 / control region 1482 are in contact with the wall of the control chamber or in contact with the spacer elements 50 of the pump chamber 181). However, if air is present in pump chamber 181, the change in volume of the control chamber will actually be distributed between the volume of the control chamber and the air bubble (s) in pump chamber 181. As a result, the calculated change in volume for the control chamber using the known initial volume of the control chamber system will not equal the calculated change in volume for the reference chamber, thus signaling the presence of air in the pump chamber.
If there is air in pump chamber 181, the initial volume of the control chamber system Vdi is in fact equal to the sum of the volume of the control chamber and the lines LO and L1 (referred to as Vdfix) plus the initial volume of the air bubble in pump chamber 181, (referred to as Vbi), as shown in Equation 9:
Vdi = Vbi + Vdfix (9)
With the membrane 15 / control region 1482 pressed against the wall of the control chamber at the end of a fill blow, the volume of any air gap in the control chamber, for example, due to the presence of grooves or other characteristics on the wall of the control chamber, and the volume of the LO and L1 lines - together with Vdfix - can be known very precisely. (Similarly, with the membrane 15 / control region 1482 pressed against the separator elements 50 of the pump chamber 181, the volume of the control chamber and lines LO and L1 can be
229 know exactly). After a fill blow, the volume of the control chamber system is tested using a positive control chamber preload. Any discrepancy between this tested volume and the tested volume at the end of the fill stroke can indicate a volume of air present in the pump chamber. By substituting Equation 9 into Equation 7, the change in volume of the control chamber ÁVd is given by:
ÁVd = (Vbi + Vdfix) (- 1 + (Pdf / Pd¡) <sup>_ (1 / γ)</sup>) (10)
Since ÁVr can be calculated from Equation 6, and we know from Equation 5 that ÁVr = (-1) ÁVd, Equation 10 can be rewritten as:
(-1) ÁVr = (Vbi + Vdfix) (- 1 + (Pdf / Pdi)<sup>_ (1 / γ)</sup>) (11) and again as:
Vbi = (-1) ÁVr / (- 1 + (Pdf / Pd¡)<sup>_ (1 / γ)</sup>) - Vdfix (12)
Accordingly, cycler 14 can determine if there is air in pump chamber 181, and the approximate volume of the bubble using Equation 12. This calculation of the air bubble volume can be performed if, for example, the absolute values of ÁVr (as determined from Equation 6) and ÁVd (as determined from Equation 7 using Vdi = Vdfix) are not equal to each other. That is, Vdi should be equal to Vdfix if no air is present in pump chamber 181, and thus the absolute value for ÁVd given by Equation 7 using Vdfix instead of Vdi
230 will be equal to AVr.
After a fill blow has been completed, and if air is detected in accordance with the methods described above, it can be difficult to determine if the air is located on the side of the pump chamber or the control side of the membrane. . Air bubbles may be present in the liquid being pumped, or there may be residual air on the control (pneumatic) side of the pump membrane 15 due to a condition (such as an occlusion) during pumping that caused an incomplete pump stroke, and incomplete filling of the pump chamber. At this point, an adiabatic FMS measurement using a negative pump chamber preload can be done. If this FMS volume matches the FMS volume with the positive preload, then the membrane is free to move in both directions, which implies that the pump chamber is only partially filled (possibly, for example, to an occlusion). If the negative pump chamber preload FMS volume value equals the nominal control chamber air volume when the membrane 15 / region 1482 is in contact with the inner wall of the control chamber, then it is possible to conclude that there is an air bubble in the liquid on the side of the flexible diaphragm pump chamber.
Head Height Detection
In some circumstances, it may be helpful to determine the location of the patient in relation to the cassette 24 or other portion of the patient's height.
231 system. For example, dialysis patients in some circumstances may detect a "jerk" or other movement due to fluid flowing into or out of the patient's peritoneal cavity during a filling or draining operation. To reduce this sensation, cycler 14 can reduce the pressure applied to patient line 34 during filling and / or draining operations. However, to properly set the pressure for patient line 34, cycler 14 can determine the height of the patient relative to cycler 14, warmer bag 22, the drain, or other portion of the system. For example, when performing a filling operation, if the patient's peritoneal cavity is located 1.52 m above the warmer bag 22 in the cassette 24, the cycler 14 may need to use a higher pressure in the patient line 34 to supply dialysate if the patient's peritoneal cavity is located 1.52 m below the cycler
14. The pressure can be adjusted, for example, by alternately opening and closing a binary pneumatic source valve for varying time intervals to achieve the desired target pump chamber pressure. An average desired target pressure can be maintained, for example, by adjusting time intervals to keep the valve open when the pump chamber pressure is below the target pressure by a specified amount, and to keep the valve closed when the Pump chamber pressure is above target pressure by a specified amount. Any adjustments to maintain a full blow volume supply can be made by adjusting fill times
232 and / or supply of the pump chamber. If the variable orifice source valve is used, the pressure of the target pump chamber can be achieved by varying the orifice of the source valve in addition to regulating the time of the intervals during which the valve opens and closes. To adjust for the patient position, cycler 14 may momentarily stop fluid pumping, leaving patient line 34 in open fluid communication with one or more pump chambers 181 in the cassette (eg, by opening suitable valve ports on cassette 24). However, other fluid lines can be closed, such as upper valve ports 192 for pump chambers 181. In this condition, the pressure in the control chamber for one of the pumps can be measured. As is well known in the art, the pressure is correlated to the height of the "head" of the patient, and can be used by cycler 14 to control the pressure of fluid delivery to the patient. A similar approach can be used to determine the height of the "head" of the heater bag 22 (which will generally be known) and / or the solution containers 20, since the height of the head of these components can have an effect over the pressure necessary to pump fluid adequately.
Cycler Noise Reduction Features
In accordance with aspects of the invention, cycler 14 may include one or more features to reduce noise generated by cycler 14 during operation and / or when it is not operating. In one aspect
233 of the invention, cycler 14 may include a single pump that generates both pressure and vacuum that are used to control the various pneumatic systems of cycler 14. In one embodiment, the pump can simultaneously generate both pressure and vacuum, thereby reducing the time it takes global operation and allowing the pump to run more slowly (and therefore more quietly). In another embodiment, the start and / or stop of the air pump can be regulated, for example, slowly increase the pumping speed or power output at the start and / or slowly decrease the pumping speed or power output in the closing. This arrangement can help reduce the “on / off” noise associated with starting and stopping the air pump so the noise from the pump is less noticeable. In another embodiment, the air pump can be operated at a lower duty cycle when it approaches a target pressure flow rate or outlet volume so the air pump can continue to operate as opposed to shutdown, only to turn on after a short time. As a result, alteration caused by repeated on and off cycles of the air pump can be avoided.
Figure 44 shows a perspective view of an interior section of cycler 14 with the upper portion of housing 82 removed. In this illustrative embodiment, cycler 14 includes a single air pump 83, which includes the actual pump and the motor driver contained within a sound barrier housing. The sound barrier housing includes an exterior shield, such as a metal or plastic frame, and a
2. 3. 4 Sound insulation material within the outer shell and at least partially surrounding the motor and pump. This air pump 83 can simultaneously supply air pressure and vacuum, for example, to a pair of accumulator tanks 84. One of the tanks 84 can store positive pressure air, while the other stores vacuum. A suitable manifold and valve arrangement can be coupled to tanks 84 to supply and control air pressure / vacuum supplied to cycler components.
14.
In accordance with another aspect of the invention, components that require a relatively constant pressure or vacuum supply during cycler operation, such as an occluder, can be isolated from the air / vacuum pressure source for at least relatively long periods of time . For example, occluder 147 in cycler 14 generally requires constant air pressure in the bladder of occluder 166 so that the patient and drain lines remain open for flow. If cycler 14 continues to operate properly without power failure, etc., bladder 166 may be inflated once at the beginning of system operation and remain inflated until it is turned off. The inventors have recognized that in some circumstances air-powered devices that are relatively static, such as the bladder 166, may "squeak" or otherwise make noise in response to slight variations in the supplied air pressure. Such variations can cause the bladder 166 to change size slightly, causing associated mechanical parts to
235 move and potentially make noise. In accordance with an aspect of the bladder 166 and other components having similar pneumatic power requirements, they can be isolated from the air pump 83 and / or the tanks 84, for example, by closing a valve, to reduce pressure variations in the bladder or other pneumatic component, thus reducing the noise that can be generated as a result of pressure variations. Another component that can be isolated from the pneumatic supply in the bladder at door 141 at cassette mounting location 145 which is inflated to press cassette 24 against control surface 148 when door 141 is closed. Other suitable components can be isolated as desired.
In accordance with another aspect of the invention, the speed and / or force at which the pneumatic components are driven can be controlled to reduce the noise generated by the operation of the component. For example, movement of valve control regions 181 to move a corresponding portion of the membrane in cassette 15 to open or close a valve port in cassette 24 can cause a "snap" noise as membrane 15 it is struck against and / or pulled from the cassette 24. Said noise can be reduced by controlling the operating speed of the valve control regions 1481, for example, by restricting the air flow rate used to move the control regions 1481. Air flow can be restricted, for example , by providing a suitably small size hole in the line leading to the associated control chamber, or in other ways.
236
A controller can also be programmed to apply pulse amplitude modulation (PWM) to the activation of one or more pneumatic source valves in a cycler manifold 14. The pneumatic pressure supplied to various valves and cassette pumps 24 can be controlled by causing associated manifold source valves to repeatedly open and close during the period of actuation of a valve or pump in cassette 24. The rate of pressure rise or fall against the membrane 15 / control surface 148 can be controlled by modulating the duration of the "on" portion of the particular manifold valve during the actuation period. An additional advantage of applying PWM to manifold source valves is that variable pneumatic pressure can be supplied to cassette components 24 using only a binary source valve (on / off), rather than a variable orifice source valve. more expensive and potentially less reliable.
In accordance with another aspect of the invention, movement of one or more valve elements can be adequately damped to reduce noise generated by valve cycling. For example, a fluid (such as a ferrofluid) can be provided with the valve element of high-frequency solenoid valves to dampen the movement of the element and / or reduce noise generated by movement of the valve element between the open and closed positions. .
In accordance with another modality, pneumatic control line vents can be connected together and / or directed to an isolated space
237 to the common sound so that the noise associated with the release of air pressure or vacuum can be reduced. For example, when the occluder bladder 166 is vented to allow spring plates 165 to move toward each other and occlude one or more lines, the released air pressure can be released in a sound-insulated housing, as opposed to being released in a space where the noise associated with the release can be heard more easily. In another embodiment, lines that are arranged to release air pressure may be connected together with lines that are arranged to release an air vacuum. With this connection (which can include an air vent, an accumulator or other), the noise generated by the pressure / vacuum release can be further reduced.
Control system
The control system 16 described in connection with Figure 1 has many functions, such as controlling dialysis therapy and communicating information related to dialysis therapy. Although these functions can be handled by a single computer or processor, it may be desirable to use different computers for different functions so that implementations of those functions are kept physically and conceptually separate. For example, it may be desirable to use one computer to control the dialysis machinery and another computer to control the user interface.
238
Figure 45 shows a block diagram illustrating an exemplary implementation of control system 16, wherein the control system comprises a computer that controls the dialysis machinery (an "automation computer" 300) and a separate computer that controls the user interface (a "user interface computer" 302). As will be described, the functions of the security critical system can only be operated on the automation computer 300, such that the user interface computer 302 is isolated from executing security critical functions.
Automation computer 300 controls hardware, such as valves, heaters, and pumps, that implement dialysis therapy. In addition, the automation computer 300 sequences the therapy and maintains a "model" of the user interface, as further described herein. As shown, automation computer 300 comprises a computer / memory processing unit 304, a flash disk file system 306, a network interface 308, and a hardware interface 310. Hardware interface 310 is coupled to detectors / actuators 312. This coupling allows the automation computer 300 to read the detectors and control the hardware actuators of the APD system to monitor and perform therapy operations. Network interface 308 provides an interface for coupling automation computer 300 to user interface computer 302.
239
The user interface computer 302 controls the components that enable data exchange with the outside world, including user and external devices and entities. User interface computer 302 comprises a memory / computer processing unit (CPU) 314, a flash disk file system 316, and a network interface 318, each of which may be the same as or similar to their counterparts in the automation computer 300. The Linux operating system can operate on each of the automation computer 300 and the user interface computer 302. An exemplary processor that may be suitable to be used as the CPU of the automation computer 300 and / or to be used as the CPU Computer User Interface 302 is Freescale's Power PC 5200B®.
Via network interface 318, user interface computer 302 can be connected to automation computer 300. Both automation computer 300 and user interface computer 302 can be enclosed within the same APD system chassis. Alternatively, one or both computers or a portion of such computers (eg, display 324) may be located outside the chassis. Automation computer 300 and user interface computer 302 may be coupled by a wide area network, a local area network, a bus structure, a wireless connection and / or some other means of data transfer.
240
Network interface 318 can also be used to couple user interface computer 302 to Internet 320 and / or other networks. Such a network connection can be used, for example, to initiate connections to a clinic or clinic doctor, upload therapy data to a remote database server, obtain new prescriptions from a clinic doctor, update application software, Obtain service support, require supplies and / or export data for maintenance use. In accordance with an example, call center technicians can access alarm logs and machine configuration information remotely on Internet 320 through network interface 318. If desired, user interface computer 302 it may be configured in such a way that connections can only be initiated by the user or otherwise locally by the system, and not by remote initiators.
The user interface computer 302 also comprises a graphics interface 322 that is coupled to a user interface, such as user interface 144 described in connection with Figure 10. In accordance with an exemplary implementation, the user interface comprises a display 324 that includes a liquid crystal display (LCD) and is associated with a touch screen. For example, a touch screen can be superimposed on the LCD so that the user can provide input to the user interface computer 302 by touching the screen with a finger, stylus, or the like. The display may also be associated with an audio system capable of playing, among other things, messages from
241 recorded audio and voices. The user can adjust the brightness of the 324 display based on their environment and preference. Optionally, the APD system can include a light detector and the brightness of the screen can be automatically adjusted in response to the amount of ambient light detected by the light detector.
The brightness of the screen can be set by users for two different conditions: high ambient light and low ambient light. The light detector will detect the ambient light level and the control system 16 will set the screen brightness to the preselected levels for either high or low ambient light based on the measured ambient light. The user can select the brightness level for high and low ambient light by selecting a value from 1 to 5 for each condition. The user interface can be a slider bar for each condition. In another example the user can select a number. The control system can set the button light levels to match the light levels on the screen.
The LCD and / or the touch screen of the 324 screen may develop faults, where it does not show and / or respond correctly. One theory, but not the only theory, of the cause is an electrostatic discharge from a user to the screen that changes the values in the controller memories for the LCD and touch screen. UIC 354 executive software or AC 354 executive processes may include a low priority thread or thread that checks constant logs of
242 driver memory for touch screen and LCD display. If the thread finds that any of the values in the memory registers are different from those stored elsewhere on the User Interface 302 computer or on the automation 300 computer, then the thread prompts another software process to reset the drivers for the LCD screen and / or the touch screen. In one embodiment, the LCD screen is controlled by a Kieko Epson S1 d 13513 integrated circuit and the touch screen is controlled by a Wolfson Microelectronics WM97156 integrated circuit. Examples of constant register values include, but are not limited to the number of pixels displayed on the screen, the number of colors displayed.
Furthermore, the user interface computer 302 comprises a USB interface 326. A data storage device 328, such as a USB flash drive, can be selectively coupled to the user interface computer 302 via the USB interface 326. The data storage device 328 may comprise a "patient data key" used to store specific patient data. Dialysis therapy data and / or survey questions (eg, weight, blood pressure) can be recorded to the patient data key. In this way, patient data can be accessible to user interface computer 302 when coupled to USB 326 interface and portable when removed from the interface. The patient data key can be used to transfer data from one system or cycler to another
243 during a cycler exchange, transferring a new therapy data configuration and cycler configuration from the clinical software to the system, and transferring treatment history information and device history from the system to the clinical software. An exemplary patient data key 325 is shown in Figure 65.
As shown, patient data key 325 comprises connector 327 and housing 329 coupled to the connector. Patient data key 325 may optionally be associated with a dedicated USB port 331. Port 331 comprises a depression 333 (eg, in the APD system chassis) and a connector 335 arranged within the depression. The depression may be defined, at least in part, by a housing 337 associated with port 331. The patient data key connector 327 and port connector 335 are adapted to be selectively electrically and mechanically coupled to each other. As can be seen in Figure 65, when the patient data key connector 327 and the port connector 335 are coupled, the housing 329 of the patient data storage device 325 is received at least partially inside the depression 333.
Housing 329 of patient data key 325 may include visual cues indicative of the port with which it is associated and / or configured to prevent improper insertion. For example, depression 333 and / or housing 337 of port 331 may have a shape corresponding to the shape of housing 329 of the data key of the
244 patient 325. For example, each may have a non-rectangular or otherwise irregular shape, such as an oblong shape with a top slit as shown in Figure 65. Depression 333 and / or port 337 housing 337 and housing 329 of patient data key 325 may include additional visual cues to indicate association. For example, each can be formed from the same material and / or have the same or similar color and / or pattern.
In a further embodiment, as shown in Figure 65A, the housing 329 of the patient data key 325 can be constructed to lean away from the connector 327 to carry any liquid that may splash on the key 325 away from the connector 327 and toward the opposite end of housing 329, where a hole 339 in housing 329 can help drain fluid out and away from patient data key 325 and its engagement with port connector 335.
In one embodiment, port 331 and depression 333 are located on front panel 1084 of cycler 14 as shown in Figure 9-11. Patient data key 325 is inserted into port 331 before door 141 is closed and therapy is started. Door 141 includes a second depression 2802 to accommodate patient data key 325, when door 141 is closed. Placing the patient data key 325 behind door 141 ensures that all therapy data can be recorded on the PDK. This location prevents the user from removing the key in the middle of therapy.
245
Alternatively or additionally, the patient data key 325 may comprise a verification code that is readable by the APD system to verify that the patient data key is of an expected type and / or origin. Said verification code can be stored in a memory of the patient data key 325, and can be read from the patient data key and processed by means of an APD system processor. Alternatively or additionally, said verification code may be included on an exterior of patient data key 325, for example, as a barcode or numeric code. In this case, the code can be read by means of a camera and an associated processor, a barcode scanner or other code reading device.
If the patient data key is not inserted when the system is on, an alert may be generated requiring the key to be inserted. However, the system may be able to operate without the patient data key as long as it has been previously configured. Therefore, a patient who has lost their patient data key can receive therapy until a replacement key can be obtained. The data can be stored directly to the patient data key or transferred to the patient data key after being stored in the user interface computer 302. The data can also be transferred from the patient data key to the computer User interface 302.
Additionally, a USB Bluetooth adapter can be attached
246
330 to user interface computer 302 via USB interface 326 to allow, for example, data to be exchanged with nearby Bluetooth enabled devices. For example, a Bluetooth-enabled scale in the vicinity of the APD system can wirelessly transfer information regarding patient weight to the system via the USB 326 interface using the USB 330 Bluetooth adapter. Similarly, a Bluetooth-enabled sphygmomanometer can wirelessly transfer information regarding the patient's blood pressure to the system using the Bluetooth 330 USB adapter. The Bluetooth adapter can be integrated into the user interface computer 302 or it can be external (for example, a Bluetooth hardware key).
The USB 326 interface can comprise multiple ports, and those ports can have different physical locations and can be used for a different USB device. For example, it may be desirable to make the USB port for the patient data key accessible from the front of the machine, while another USB port can be provided on and accessible from the rear of the machine. A USB port for Bluetooth connection can be included on the outside of the chassis, or rather can be located inside the machine or inside the battery door, for example.
As noted earlier, functions that could have critical security indications can be isolated on the computer from
247 automation. Critical security information refers to APD system operations. For example, critical safety information may comprise a status of an APD procedure and / or algorithms for implementing or monitoring therapies. Non-critical security information may include information that relates to the display of the screen that is not material to the operations of the APD system.
By isolating functions that could have critical security implications on automation computer 300, user interface computer 302 can be relieved from handling critical security operations. Therefore, problems with or changes to the software running on the user interface computer 302 will not affect the delivery of therapy to the patient. Consider the example of graphics libraries (for example, the Trolltech's Qt® toolbox), which the user interface computer 302 can use to reduce the amount of time required to develop the user interface view. Because these libraries are managed by a separate processor and process from those of the automation computer 300, the automation computer is protected from any potential defects in the libraries that could affect the rest of the system (including security critical functions) if they are handled by the same processor or process.
Of course, although user interface computer 302 is responsible for presenting the interface to the user, the data may also be entered by the user through the use of the user computer.
248 user interface 302, eg, via display 324. To maintain isolation between the functions of automation computer 300 and user interface computer 302, the data received by display 324 may be sent to the automation computer. for interpretation and return to the user interface computer for display.
Although Figure 45 shows two separate computers, separation of storage and / or execution of critical security functions from storage and / or execution of non-critical security functions can be provided by having a single computer that includes separate processors, such as components. of CPU / memory 304 and 314. Therefore, it should be appreciated that the provision of separate processors or "computers" is not necessary. Furthermore, an individual processor can alternatively be used to perform the functions described above. In this case, it may be desirable to functionally isolate the execution and / or storage of the software components that control the dialysis machinery from those that control the user interface, although the invention is not limited in this regard.
Other aspects of the system architecture may also be designed to address security concerns. For example, automation computer 300 and user interface computer 302 may include a "secure line" that can be enabled or disabled by the CPU on each computer. The secure line can be coupled to a
249 A voltage supply that generates enough voltage (eg, 12V) to enable at least some of the APD system's 312 detectors / actuators. When both the automation computer CPU 300 and the user interface computer CPU 302 send an enable signal to the safe line, the voltage generated by the voltage supply can be transmitted to the detectors / actions to activate the disable certain components. Voltage, for example, can activate the pneumatic valves and the pump, disable the occluder, and enable the heater. When the CPU stops sending the enable signal to the safe line, the voltage path can be interrupted (for example, by a mechanical relay) to disable the pneumatic valves and pump, enable the occluder, and disable the heater. In this way, when either the automation computer 300 or the user interface computer 302 deems it necessary, the patient can be quickly isolated from the fluid path, and other activities such as heating and pumping can be stopped. Each CPU can disable the secure line at any time, such as when a critical security error is detected or a software watcher detects an error. The system can be configured in such a way that, once disabled, the security line may not be restored until the automation computer 300 and the user interface computer 302 have completed self-tests.
Figure 46 shows a block diagram of the user interface computer 302 software subsystems and the
250 automation computer 300. In this example, a “subsystem” is a collection of software, and perhaps hardware, assigned to a specific set of related system functionality. A “process” can be a separate executable that operates in its own virtual address space and passes data to other processes that use interprocess communication facilities.
This executive subsystem 332 includes the software and scripts used for inventory, verification, initiation, and execution monitoring of the software operating on the CPU of the automation computer 300 and the CPU of the user interface computer 302. A process is run common executive on each of the preceding CPUs. Each executive process loads and monitors the software on its own processor and monitors the executive on the other processor.
The user interface (Ul) 334 subsystem handles system interactions with the user and the clinic. The Ul 334 subsystem is implemented in accordance with a "model view controller" design pattern, which separates the display of the data ("view") from the data itself ("model"). In particular, system data and status modification functions ("model") and cycler control functions ("controller") are handled by the Ul model and cycler controller 336 on the automation computer 300, while the The "view" portion of the subsystem is handled by the Ul 338 screen view on the Ul 302 computer. The data display and export functionality, such as the
251 Log view or remote access, can be fully managed by Ul 338 screen view. Ul 338 screen view monitors and controls additional applications, such as those that provide log view and a clinical interface. These applications are swapped in a window controlled by the Ul 338 screen view so that control can be returned to the Ul 338 screen view in the event of an alert, alarm, or error.
Therapy subsystem 340 directs and regulates the timing of delivery of dialysis treatment. You may also be responsible for verifying a transcript, calculating the number and duration of therapy cycles based on prescription, time and available fluids, monitoring therapy cycles, tracking fluid in supply bags, tracking fluid in the heater bag, track the amount of fluid in the patient, track the amount of ultra-filtrate removed from the patient, and detect alert or alarm conditions.
Machine control subsystem 342 controls the machinery used to implement dialysis therapy, orchestrate the high level of pumping and control functionality when required by therapy subsystem 340. In particular, the following control functions can be performed by the machine control subsystem 342: control of the air compressor; heater control; fluid supply control (pumping); and measurement of fluid volume. The machine control subsystem 342 also sends signals from the detectors reading through the
252 iste / Ο 344 subsystem, described later.
The l / O subsystem 344 in automation computer 300 controls access to the detectors and actuators used to control therapy. In this implementation, the l / O 344 subsystem is the only application process that directs access to the hardware. Therefore, the l / O 344 subsystem publishes an Interface to allow other processes to obtain the status of the hardware inputs and set the status of the hardware outputs.
FPGA
In some embodiments, Hardware Interface 310 in Figure 45 can be a separate processor from automation computer 300 and User Interface 302 that can perform a defined set of machine control functions and provide an additional layer of security to the machine. cycler controller 16. A second processor, such as a field programmable portal array (FPGA) can increase the responsiveness and speed of cycler 14 by moving some computational tasks from automation computer 300 to hardware interface 310 (for example, an FPGA), so that automation computer 300 can devote more resources to fluid management and therapy control, as these comprise resource intensive calculations. Hardware interface 310 can control pneumatic valves and temporarily record and store data from the various detectors. Real-time control of valves, pressure levels and
253 Recording data by means of hardware interface 310 allows the automation computer 300 to send commands and receive data, when the processes or software functions that are running on the automation computer 300 are ready for them.
A hardware interface processor 310 can be advantageously implemented over any medical fluid delivery apparatus, including (but not limited to) a peritoneal dialysis cycler 14, in which fluid is pumped by means of one or more pumps and a provision of one or more valves of one or more fluid source containers (eg, dialysate solution bags or a heating bag containing fluid to be infused) to a patient or user. It can also be implemented on a fluid delivery apparatus that is configured to pump fluid from a patient or user (eg, peritoneal dialysis cycler) to a receptacle (eg, a drain bag). A main processor may be dedicated to controlling the proper sequence and timing of pumps and valves to perform specific functions (for example, pumping from a solution bag to a warmer bag, pumping from a warmer bag to a user, or pumping from a user to a drain pan), and monitor the volumes of fluid pumped from one location to the next. A secondary processor (hardware interface) (for example, an FPGA) may be correspondingly dedicated to collecting and storing data received from various detectors (for example,
254 pressure detectors associated with the pumps, or temperature detectors associated with a heating system) at an uninterrupted fixed speed (for example, approximately 100 Hz or 200 Hz), and store the data until required by the main processor. You can also control the pumping pressures of the pumps at a speed or on a schedule that is independent of any processes occurring in the main processor. In addition to other functions (see below) you can also open or close individual valves at the command of the main processor.
In one example, Hardware Interface 310 may be a processor that performs many functions including, but not limited to:
• Acquire data from the pneumatic pressure detector on a predictable and fine resolution time basis;
• Store the pressure data with a time stamp until required by the automation computer 300;
• Validate the messages received from that automation computer 300;
• Provide automated control of one or more pneumatic valves;
• Control some valves with a pulse width modulation (PWM) duty cycle to provide Take & Hold functionality and / or control some valves with current feedback;
255 • Provide combinations of automated valves and redundant verifiers of safety, maximum pressures and temperatures and skill.
• Regardless of the other 300, 302 computers, put cycler 14 in a failsafe mode as needed.
• Monitor the state of the buttons on cycler 14 and control the level of button illumination;
• Control the Auto Connect 1321 screwdriver mechanism and monitor Auto Connect position detection;
• Detect the presence of solution caps 31 and / or spike caps 63;
• Check the pneumatic pump;
• Control the main LED detector and the detector;
• Detect over-voltages and test hardware to detect over-voltages;
• Control and monitor one or more fluid detectors;
• Monitor latch 1080 and proximity switch 1076 on door 141;
• Monitor critical voltages at the system level.
Hardware Interface 310 may comprise a processor separate from the processors in automation computer 300 and user interface 302, A-to-D conversions, and one or more IO boards. In
256 In another embodiment, the hardware interface comprises an FPGA (Field Programmable Gate Array). In one embodiment, the FPGA is a SPARTAN®3A in gate 400K and 256 ball package made by Xilinx Inc. of California. Hardware Interface 310 is a smart entity that is used to operate as a separate security monitor for many of the Control CPU functions. There are several critical security operations where either the Hardware Interface or the Control CPU serves as the primary controller and the other serves as the monitor.
Hardware interface 310 serves to monitor the following functions of automation computer 300, including but not limited to:
• Monitor the integrity of the system control data being received from the automation computer 300;
• Evaluate the valve configurations ordered for combination that could create a risk to the patient during therapy;
• Monitor fluid and pan temperature for excessively high or low temperatures;
• Monitor and test the over-voltage monitor; and • Provide a means for the automation computer 300 to validate critical data from the hardware interface.
Figure 45A is a schematic representation of an arrangement of the automation computer 300, the Ul computer 302
257 and hardware interface processor 310. Hardware interface 310 is connected via a communication line to automation computer 300 and connects detectors and actuators 312 to cycler 14. A supply voltage 2500 provides power to actuators for Critical security that can be enabled or disabled through 300, 302, 310 computers. Safety critical actuators include but are not limited to pneumatic valves, the pneumatic pump, and a safety relay on the heater circuit. The pneumatic system is configured for safe condition when not powered on. The safe pneumatic condition may include occluding lines 28, 34 to the patient, isolating control chambers 171 and / or closing all valves 184, 186, 190, 192 on cassette 24. Safety relay 2030 in heater circuit 2212 is open, preventing electrical heating, when the relay is not on. Each computer 300, 302, 310 controls a separate electrical switch 2510 that can interrupt power to the valves, pump, and safety relay. If any one of the three computers detects a failure condition, you can put the cycler in a failsafe condition by opening one of the three 2510 switches. The electrical switches 2510 are controlled by the security executive process 352, 354 on the Ul 302 computer and the automation computer 300 respectively.
Figure 45B is a schematic illustration of the connections between Hardware Interface 310, the various detectors, the valves
258 pneumatic, heater bag, and automation computer 300. Hardware Interface 300 controls each of the 2660-2667 pneumatic valves and 2600 pneumatic pump or compressor via pulse width modulated DC voltages. Figure 45B presents an alternative embodiment of the 2632 safe line supplying power to the 2660-2667 pneumatic valves, the 2600 pump, and the 2030 heater safety relay, in which a single switch 2510 is powered by a connected AND 2532 gate. to the three computers 300, 302, 310. The main detector is controlled and monitored by Hardware Interface 310. The brightness of the LED buttons is controlled by the Hardware Interface 310 via a voltage treated with PWM.
The data signals from the buttons, pressure detectors, temperature detectors, and other items listed in Figure 45B are monitored by Hardware Interface 310, and the data is stored in a buffer memory until required by the automation 300. The digital inputs are directly connected to Hardware Interface 310. Analog pressure, temperature, current detector, and other signals are connected to Analog-to-Digital-Converter (ADC) boards that convert analog signals to digital values and can scale and / or offset digital values. The ADC outputs are communicated on SPI buses to Hardware Interface 310. Data is recorded and stored in buffer memory at a fixed rate. Some of the data signals are
259 They can record at a relatively slow rate, including pressure data on pressure traps and fluid traps, temperatures, and current measurements. Low velocity data can be recorded at 100 Hz. The adiabatic FMS volume measurement algorithm can be enhanced with high velocity pressure data that is recorded at regular intervals. In a preferred embodiment, the pressure data from the detectors on the control volume 171 and the reference chamber 174 are recorded at 2000 Hz. The data can be stored in random-access-memory (RAM) together with a mark. of time. The data collection rate can preferably proceed independently of the automation computer 300 and the processes or sub-routines on the hardware interface. The data is reported to automation computer 300, when a process requests that value.
Data transfer between hardware interface 310 and automation computer 300 can occur in a two-step process where a data packet is transferred and stored in a buffer before being validated and then accepted for use by the computer. receiver. In one example, the sending computer transmits a first data packet, followed by a second transmission of the cyclic redundancy check (CRC) value for the first data packet. The receiving computer stores the first data packet in a buffer and calculates a new first data packet CRC value. The receiving computer then compares the CRC value just
260 calculated with the received CRC value and accepts the first data packet if the two CRC values match. Cyclic Redundancy Verification (CRC) is an error detection code commonly used in digital networks and storage devices to detect accidental changes in hard data. The data blocks that enter these systems have a short verification value, based on the remainder of a polynomial division of their content; upon retrieval the calculation is repeated, and corrective actions can be taken against possible data corruption if the verification values do not match. Data is not transferred between the automation computer and the hardware interface if the CRC values do not match. If multiple consecutive data packets fail the CRC test, the receiving computer can signal an alarm and put the machine into a failsafe condition by removing power from the 2632 safe line. In one example, the alarm condition occurs on the third consecutive CRC verification failed.
Automation computer 300 passes commands to open selected valves and set specified pressures at specified volumes to hardware interface 300. Hardware interface 310 in turn controls the valve position by providing a PWM-treated voltage to each valve. Hardware interface 310 opens the valves as required with a take-and-hold algorithm, where the valve is initially operated with a high voltage or current, and then held in place with a lower voltage or current. The take-and-hold operation of the
261 Valves can advantageously reduce energy consumption and the level of heat dissipation within cycler 14.
The hardware interface 310 controls the pressure at the specified volume by opening and closing the valves between the specified volume and the appropriate pressure reservoir based on the pressure measured at the specified volume. The hardware interface 310 can also control the pressure in the pressure tanks by opening and closing the valves between a pneumatic pump and one of the pressure tanks based on the pressure measured in the tank. The specified volumes may include each of the control chambers 171, the reference volumes 174, the fluid trap, and the positive and negative deposits. The hardware interface 310 can control the pressure at each of these specified volumes via many control schemes, including but not limited to on-off control or proportional valve control with a PWM signal. In one example, as described above, hardware interface 310 implements an on-off controller, sometimes referred to as an explosion-explosion controller, that sets first and second limits and closes the valve when the pressure exceeds the second upper limit and opens the valve when the pressure is less than the first lower limit. In another example, hardware interface 310 can operate valves between the specified volume and both pressure vessels to achieve a desired pressure. In other examples, automation computer 300 may specify one or more valves and order that one
262 specific valve monitor pressure as measured by a specified detector.
Hardware interface 310 controls the position and operation of the Auto-Connect carriage. The movement and positioning of the AutoConnect cart 146 is controlled in real time by means of the hardware interface over the measured position of the cart 46. The automation computer 300 can command a particular function or position for the cart. Hardware interface 310 performs the ordered function without memory overhead or processing of automation computer 300. The positioning of the carriage 146 is controlled with a feedback loop from a position detector. Additionally, the FPGA detects the presence of solution caps 31 and / or spigot caps 63 with detector elements 1112 as described above. Alternatively, the presence of caps 31 and / or spigot caps 63 can be detected by means of a wide variety of detection technology, including but not limited to vision systems, optical detectors which can be locked by means of a solution and / or spigot cap, or, for example, a microswitch on the separator element 1491.
Hardware interface 310 can implement security functions independently of automation computer 300 or user interface computer 302. The independent action of hardware interface 310 to disable security line 2632 and / or signal an alarm to security executives 352, 354 additionally
263 reduces the chance of an unsafe condition occurring. Hardware interface 310 can send an alarm and / or cut off power to the safe line 2632 for defined valve combinations at any time. Disabling the cycler based on valve positions not allowed protects the patient and retains the ability to complete therapy (after a restart if necessary). The hardware interface 310 can also alarm and remove power from the safe line in unsafe conditions including excessive temperature on the heater tray and / or button on the bag, excessive pressure in the control chamber or reservoir. The hardware interface can alarm and remove power from the safe line when water is detected in the fluid trap.
Heater Control System
The control systems described above can be used to ensure that the solution supplied to the patient is kept within a predetermined range of temperatures. During the therapy process, cycler 14 fills heater bag 22 with solution from connected solution containers 20, via a heater bag line 26. Heater bag 22 rests on heater tray 142 which may include heaters of electrical resistance. Heater bag 22 can be covered with an insulated cover 143. A heater controller can operate to control the thermal energy supplied to heater tray 142 to control the temperature of
264 the solution to a desired set point before supplying the solution to the patient. The temperature of the solution should be within a safe range before being delivered to the patient's abdominal cavity to avoid injury or cause discomfort to the patient, or cause hypothermia or hyperthermia. The heater controller can also limit the temperature of the heater tray to touch safe temperatures. The heater controller is built to heat and maintain the solution within an acceptable temperature range in a timely manner to ensure the most effective therapy.
Figure 49-1 is a schematic view of an exemplary embodiment of a solution heater system 500. In this example, the solution heater system 500 is located within housing 82 of cycler 14. The housing includes an insulated cover 143 which may be attached to the top of the housing 82. The housing 82 and the heater cover 143 can therefore define a region that serves to house the components of the solution heater system 500. The solution heater system may include the following elements: housing 82, heater cover 143, heater tray 22, heater elements 508, heater tray temperature detectors 504, button temperature detector 506, insulating ring 507 and heater control electronics 50. Heater tray 142 is positioned within housing 82, and can accommodate a heater bag 22 when positioned on top of heater tray 142.
265
Preferably, the heater tray 142 is tilted to place the inlet and / or outlet of the heater bag in a dependent position, to help ensure that the fluid in the bag is always in contact with the inlet / outlet regardless of the amount of fluid in the bag. In one embodiment, up to six or more heater tray temperature detectors 504 (only one exemplary heater tray temperature detector 504 is shown in Figure 49-1) positioned along the floor of the heater tray 142 Additionally, there may be a button temperature sensor 506 positioned within the heater tray 142. The button detector 506 is positioned to make good thermal contact with the heater bag, while thermally isolating it from the heater tray 142 by means of an insulating ring 507, to provide an approximation of the temperature of the fluid or dialysate in the bag . In another embodiment, the button detector 506 may comprise a pair of thermistors mounted on an aluminum button. The aluminum button is thermally insulated by means of an insulating ring made of, for example, LEXAN® 3412R plastic or other low thermal conductivity material. The button 506 temperature detector can be located near the end of the tray where the fluid lines connect to the heater bag 22 to better measure the temperature of the fluid inside the heater bag when the heater bag is full less than about a third of capacity. The 506 button detector can also be referred to as the temperature sensor of the
266 dialyzed or fluid. There may also be a plurality of heater elements 508 positioned under the heater tray 142, further towards the upper end of the tray, with the bag detector located further towards the tray dependent portion, for the detector to provide a reading. more accurate in the temperature of the fluid within the bag, and to be relatively unaffected by the heater elements 508. The thermal output of the heater elements 508 can be controlled by means of the heater control electronics 505 to achieve the desired fluid temperature in the heater bag. Heater 505 control electronics may include but are not limited to a heater 509 control module that produces a Pulse Amplitude Modulation (PWM) signal (PWM signal 511, depicted in Figure 49-2). The electrical hardware in the input-output (IO) subsystem 344 connects electrical power to the heater elements 508 based on the signal from PWM 511, and the hardware in the IO 344 subsystem reads the output of the temperature detectors from the 504 heater tray and 506 button temperature detector. The PWM signal 511 can control the power supplied for each of the elements of the heater 508, and consequently the solution heater system 500 can then heat the heater bag 22 to a comfort temperature that can be adjusted by the user, which can be controlled within a preferred safe temperature range. The solution heater system 500 can also limit the surface temperature of
267 Heater Tray 142 at a safe touch temperature. The hardware components of the heater 505 control circuit may be part of the controller 16. There may be an insulation 510 positioned below the heater element 508 that functions to thermally isolate the heater tray 142 and the heater bag 22 from the electronic components. and cycler tires 12. Additionally, the heater cap 143 can isolate the heater bag 22 from the surrounding environment. The solution heater system 500 may thus be constructed to bring the temperature of the solution within the heater bag 22, as measured by the button temperature sensor 506, to the desired temperature of the fluid set point 550 ( see Figure 49-3) as quickly as possible, and maintain that desired fluid set point temperature 550 throughout the remainder of the therapy cycle. In some embodiments, temperature detectors connect to hardware interface 310. Hardware interface 310 itself can control a safety relay that disables the heater.
In some embodiments, the heater elements may include thermal switches that open when the switch temperature exceeds a first predetermined value. The switch will close again once the switch temperature drops below the second default lower value. The thermal switch can be incorporated directly into the heater elements or can be mounted on the outside of the heater element or on the heater tray.
268 Heater. Thermal switches provide an additional layer of protection against unsafe tray temperatures.
In another example, the thermal switch may be a thermal fuse with a one-time fuse link. A service call will be required to replace the blown thermal fuse, which may advantageously provide an opportunity to inspect and / or test cycler 14 before restarting therapy. Figure 49-2 shows a schematic block diagram of the software context of the heater control subsystem. In one embodiment, the logic of the heater control circuit 505 can be implemented as the heater control module 509 in the machine control subsystem 342 in the APD System software architecture. The heater controller software may be implemented in controller 16 (Figure 45) as described below. Additionally, the therapy subsystem 340 can provide information to the machine control subsystem 342 such as, for example, the volume of the heater bag and the set point for the button temperature sensor 506. The heater elements 508 can be enabled by the therapy subsystem 340. The machine control subsystem 342 can also read the temperature values of the l / O subsystem 344, which is located below the machine control subsystem 342. Additionally, the heater controller 509 can output a PWM signal 511 that you can then control the power supplied to the heater elements 508.
269
In one embodiment, the machine control subsystem 342 can be called periodically (eg, about every 10 milliseconds) to service the l / O subsystem 344, update variables, and detection conditions. Machine control subsystem 342 can also send updated signals to heater control module 509 periodically (eg, about every 10 ms). Updated signals may include the volume of the heater bag, the temperatures of the heater tray 515, the temperature of the button 517, the set point temperature 550 and the function that enables the heater. The heater control module may average some or all of these signals continuously, but only calculate and update its output 511 at a lower frequency (for example, every 2 seconds).
In another aspect, the solution heater system 500 may be able to control the temperature of the solution in the heater bag within a given range of a desired fluid set point temperature 550 (see Figure 49-2 and Figures 49-7 - 49-9). Additionally, the Solution 500 heater system has been designed to operate within predefined specifications under a variety of different operating conditions, such as a relatively wide range of ambient temperatures (for example, about 5 ° C to about 37 ° C) , bag fill volumes (eg, about 0 mL to about 3200 mL), and solution container temperatures 20 (eg, between about 5 ° C and
270 about 37 C). Additionally, the solution heater system 500 is capable of operating within specifications even if the solution in the heater bag 22 and the solution introduced during the make-up cycle may be at different temperatures. The Solution 500 heater system has also been designed to operate within specifications with heater supply voltages varying as much as +10% of the nominal voltage.
The solution 500 heater system can be thought of as an asymmetric system, in which the solution 500 heater system can increase the temperature of the solution with the heater elements 508, but relies on natural convection to decrease the temperature of the solution in the heater bag 22. Heat loss can be further limited by insulation 510 and insulated cover 143. One possible consequence is that in the event of excess temperature, the APD system 10 may delay filling a patient while the warmer bag slowly cools. A possible consequence of placing the heater elements on the heater tray 142 is that the heater tray 142 may be at a temperature substantially higher than that of the heater bag 22 during the heating process. A simple feedback control on the temperature of the heater bag as recorded by the button 506 temperature sensor, may not turn off the heater fast enough to prevent thermal energy from
271 higher temperature in the heater tray causes the heater bag 22 to exceed the desired temperature of set point 550. Alternatively, controlling the heaters 508 to achieve a temperature of the heater tray 504 that does not cause the temperature of the heater to be exceeded. heater bag can result in a slow heater system and therefore delay therapy.
To minimize the time for the solution in the heater bag to reach set point temperature 550 without exceeding, the heater control module may implement a control loop that varies the electrical power of the heater elements 508 to achieve a temperature desired fluid in the heater bag, in part by controlling the equilibrium temperature of the heater tray 142, the heater bag 22 and the fluid within the heater bag 22. In one embodiment, an Integral-Proportional (Pl) controller controls an equilibrium temperature 532 which is a function of the temperatures of the heater bag 22 and the heater tray 142 and the volume of solution in the heater bag. The equilibrium temperature can be understood as the temperature that the solution in the heater bag 22 and in the heater tray 142 would reach if the heater were turned off and the two components allowed to reach equilibrium. The equilibrium temperature can also be understood as the weighted average of the target temperature for heater tray 142 and the measured temperature of the solution filled heater bag, weighted by
272 the thermal capacitance of each. The equilibrium temperature can also be calculated as the weighted average of the measured temperature of the heater tray and the temperature of the solution, in which the temperatures are weighted by means of their respective thermal capacitances. In one embodiment, the weighted average temperature of the heater pan and the fluid in the heater bag can be calculated as the sum of the target temperature of the heater pan by the thermal capacitance of the heater pan plus the temperature of the fluid by the thermal capacitance of the fluid in the heater bag, where the sum is divided by the sum of the thermal capacitance of the heater pan plus the thermal capacitance of the fluid in the heater bag. The weighted averages of the heater pan and fluid may alternatively be weighted by the mass of the heater pan and fluid in the bag or the volume of the heater pan and fluid in the bag.
The equilibrium temperature control can be implemented using many control schemes, such as simple feedback loops using proportional, integral and / or derived nested controllers and loops. An embodiment of a control scheme that uses cascaded nested control loops is shown in Figure 49-3. Outer loop controller 514 can control the temperature of the heater bag measured by the button temperature sensor 506 at the temperature set point of fluid 550 by varying the
273 set point temperature of heater tray 527 supplied to inner loop controller 512. Alternatively, outer loop controller 514 can control the equilibrium temperature of heater bag 22 and heater tray 142 at the point temperature Fluid set point 550 by varying the temperature of the 527 heater tray set point. The temperature of the heater bag 22 and the fluid can be measured by means of the button 506 temperature sensor and the temperature of the heater tray can be measured by one or more temperature sensors of the heater tray 504. The outer loop controller can include one or more of the following elements: proportional controller, integral controller, derived controller, saturation limits, anti-meandering logic elements, and zero-order clamping logic elements.
Inner loop controller 512 can control the temperature of the heater tray at the temperature of the heater tray set point 527 by varying the thermal output of the heating elements 508. The temperature of the tray can be measured by one or more 504 heater tray temperature detectors. The inner loop controller can include one or more of the following elements: proportional controller, integral controller, derived controller, saturation limits, anti-meandering logic elements, and zero-order clamping logic elements.
An exemplary implementation of the
274 Heater 509 uses a cascade coupled Pl regulator with a Proportional-Integral-Derivative (PID) controller. In the embodiment of Figure 49-3, a PID 512 inner loop controller can control the temperature of the heater tray 142, and a Pl 514 outer loop controller can control the equilibrium temperature of the heater bag, the fluid in the heater bag and heater tray measured by means of the heater tray temperature detectors 504 and the button temperature detector 506. The loop controller 514 differs from a standard Pl regulator in that any excess of the desired fluid set point 550 by means of the solution heater system 500 can be minimized by means of a controllable logic integrator as further described ahead. In one embodiment, the heater pan temperature signal 515 and the button temperature sensor (heater bag) signal 517 are low pass filtered through a pair of control filters 519 at a relatively frame rate high (for example, a full frame rate of 100 Hz), while heater control module 509 can change the output of the heaters to a lower rate (for example, Vi Hz rate).
Figure 49-4 shows a schematic diagram of one embodiment of the 512 interior loop controller (heater tray controller). In this mode, the 512 interior loop controller uses a standard PID controller that includes but is not limited to one item
275 differentiator 519 to produce a temperature error and a proportional gain element 522 to create a PWM signal 511. Inner loop controller 512 may further include a discrete time integrator 516 to reduce offset error. The inner loop controller 512 may also include an anti-meander logic element 518 to minimize excess due to temperature error that exists for a long period of time when the output of the inner loop controller 512 becomes saturated. Inner loop controller 512 may further include a discrete derivative term 520 that acts on the actual temperature of heater tray 515 to improve the responsiveness of the heater. Additionally, the interior loop controller 512 may include a saturation limit element 521 that establishes a maximum and / or minimum allowed heater command or PWM signal 511. The interior loop controller 512 may also include zero-order clamp logic. 523 to keep the PWM 511 signal constant between controller calculations that occur approximately every 2 seconds.
Figure 49-5 shows a schematic diagram of the outer loop controller 514 (button temperature detector controller). In this example, the outer loop controller 514 uses a modified regulator of type Pl, which may include differentiating elements 531, an integrator 534, and a proportional gain element 526. Outer loop controller 514 may additionally include integrator shift logic 522 and corresponding switch 529, to allow
276 that the integrator be turned on and off by means of logic in the heater control module 509. The outer loop controller 514 may further include a command feed advance 524 to improve the responsiveness of the outer loop controller 514 . Outer loop controller 514 may further include a proportional feedback term 526 to act on a weighted combination of the target temperature of button temperature sensor 517 and the target temperature of heater tray 527. The resulting measurement is a temperature of equilibrium 532 as described above. The outer loop controller 514 may further include a saturation limit element 521 and / or a low-pass filter 542. The saturation limit element 521 in the outer loop sets a maximum allowable target tray temperature 527. The filter for Low Pass 542 can be designed to filter transient control signals at frequencies outside the bandwidth of Solution 500 heater system.
The integral elements 534 in the outer loop controller 514 can be turned on by means of a switch 529 when some or all conditions are present: the rate of change of the temperature of button 517 is below a predetermined threshold, the temperature of the Button 517 is within a predetermined number of degrees of fluid set point temperature 550, or the volume of the bag is greater than a predetermined minimum and none of the
277 Drivers 512, 514 is overcrowded. An equilibrium temperature feedback loop can control the transient behavior of the solution 500 heater system, and can be dominant when the surrounding ambient temperature is in a normal to high range. The action of integrator 516 can only be significant in cold environments, which can result in a substantial temperature difference between the actual temperature of the button detector 517 and the actual temperature of the heater tray 515 in equilibrium. Feed advance term 524 can pass the temperature of fluid set point 550 through the target temperature of heater tray 527. This action will initiate the target temperature of the 527 heater tray at the fluid set point temperature 550, rather than zero, thus improving the transient response of the solution 500 heater system.
Heater module 509 may also include a tester that turns off the PWM 511 signal if the actual temperature of the heater tray 515 crosses a predetermined threshold (this threshold can be set to be slightly higher than the maximum allowable target tray temperature heater 527). This tester cannot be activated under normal operation, but can be activated if the heater bag 22 is removed while the temperature of the heater tray 142 is at a predetermined maximum value.
The controller of Pl 514 can include a proportional term that acts on the equilibrium temperature 532. The equilibrium temperature
278 it is the temperature of the heater bag measured by the button detector 506 that would result if the heater 508 were turned off and if the heater tray 142 and the heater bag filled with solution 22 were allowed to equilibrate. The equilibrium temperature can be better understood by referring to Figure 49-6, which shows a block schematic diagram of heater tray 142 and heater bag 22 in a control volume analysis 546. Volume analysis Control 546 represents a model environment in which the equilibrium temperature 532 can be determined. In this illustrative embodiment, the solution heater system 500 can be modeled as a control volume 548, which may comprise at least two thermal masses: heater tray 142 and heater bag 22. The limit can be assumed to be Control Volume 548 works as a perfect insulator, in that the only heat transfer is between heater tray 142 and heater bag 22. In this model, thermal energy 549 can be added to the system via heater elements 508, but thermal energy cannot be removed from heater tray 142 and heater bag 22. In this model, as in Solution 500 heater system, it is desirable to heat heater tray 142 just enough so that heater bag 22 reaches its target temperature while heater tray 142 and heater bag 22 enter in equilibrium. Therefore, the equilibrium temperature 532 can be calculated as a function of the initial temperature of the heater bag 22 and the
279 Heater Tray 142 Initial Temperature:
E - Mp Cp Tp + Vb pb Cb Tb - (Mp Cp + Vb pb Cb) T<sub>and</sub> where M<sub>P</sub>, c<sub>p</sub> are the mass and the specific heat of the heater tray 142, V<sub>P</sub>, p<sub>b</sub>, Cb are the volume, density and specific heat of the solution in the bag, T<sub>p</sub>and T<sub>b</sub> are the temperatures of the heater tray 515 and button 517 respectively. Solving the equilibrium temperature produces a linear combination of tray and button temperatures:
T<sub>and</sub>= eT<sub>t</sub>+ (lc) T<sub>p</sub>
Vb, <sup>M</sup>p<sup>C</sup>p where K + V<sub>h</sub> and Pt £ b
The constant c is an equilibrium constant, k is the ratio of the thermal capacitance of the heater tray to the solution. The subscript b denotes the solution in the heater bag 22, while p denotes the heater tray 142.
In this model, allowing the heater module 509 to control the equilibrium temperature 532 during the initial transition can allow for rapid heating of the heater bag 22 while also reducing the actual temperature of the heater tray 515 early enough. to prevent thermal excess. Parameter c can be empirically determined. Heater module 509 can set c to a value larger than the measured value to underestimate the total energy required to reach the desired set point 550,
280 further limiting the thermal excess of the solution 500 heater system.
Figure 49-7 graphically shows the performance of the disclosed solution 500 heater system operating under normal conditions. The measured temperatures of the heater pan detectors 504, the button temperature sensor 506 and an additional temperature probe are plotted against time. The fluid temperature probe was part of the experimental setup to verify the control scheme. The fluid probe temperature is shown as line 552. The button temperature is shown as line 517 and the heater pan temperatures are shown as line 515. Line 550 is the target temperature for the button temperature 506. At the start of this test, the heater bag is substantially empty, the heater is off, and the fluid does not move, so all temperatures are at a nominal value. At a time T = 1, the fluid at 25 ° C begins to flow into the heater bag 22, lowering the temperatures of the probe and button 552, 517, while the heater turns on and increases the temperature of the heater tray 515. Under normal operation, proportional control of the equilibrium temperature 532 may be sufficient to heat the solution within the heater bag 22 to a temperature close to the desired fluid set point temperature 550. Therefore, in Figure 49 -7, the solution 500 heater system works effectively, and the actual tray temperature of the
281 Heater 515, the actual temperature of the button detector 517 and a probe temperature 552 converge to the fluid set point temperature 550 after approximately 50 minutes.
Figure 49-8 graphically shows the performance of the solution 500 heater system operated in a high temperature environment where the ambient temperature is 35 ° C. As described above, the test begins with the heater bag substantially empty. Once the fluid begins to flow and the heater turns on, the probe and button temperatures 552, 517 decrease and the temperature of the heater pan 515 increases. In a high temperature environment, the solution 500 heater system operates in a manner substantially similar to normal conditions. Thus, proportional control of the equilibrium temperature 532 again may be sufficient to heat the solution within the heater bag 22 to a temperature close to the desired fluid set point temperature 550. In Figure 49-7, the solution 500 heater system operates effectively and within desired specifications, and the actual temperature of the heater tray 515, the actual temperature of the button detector 517, and a probe temperature 552 converge at the fluid set point temperature 550 after approximately 30 minutes.
Figure 49-9 graphically shows the performance of the solution 500 heater system operated in a cold environment, where the ambient temperature is 10 ° C and the source fluid is 5 ° C. How I know
282 described earlier, the trial starts with the heater bag substantially empty. Once the fluid begins to flow and the heater turns on, the probe and button temperatures 552, 517 decrease and the temperature of the heater pan 515 increases. In a cold environment, setting the desired fluid set point temperature 550 equal to the equilibrium temperature 532 can lead to a steady state error in the temperature of the button 506 detector. Temperature loss in cold environments may require a large temperature difference between heater tray 142 and button detector 506 during thermal equilibration. Because the equilibrium temperature 532 is a weighted sum of the heater tray 142 and the button detector 506, the temperature of the button detector 506 may be below the temperature of the fluid set point 550 if the temperature of the tray The heater 142 is above the desired temperature of the equilibrium fluid set point 550. This can occur even if the equilibrium temperature 532 equals the fluid set point temperature 550. To compensate for this standard state error, an integral term can be added to the outdoor Pl controller 514 that acts on the detector temperature error. button 506. Integrator 538 can be turned on when one or more of the following conditions are met: a first derivative of the button 506 detector temperature is low; the button detector 506 is near the temperature of the fluid set point 550, the volume of the heater bag 22 exceeds a minimum threshold;
283 And neither the inner loop of PID 512 nor the outer controller of Pl 514 is saturated. In this illustrative embodiment, changing the integral term can minimize the effect of integrator 538 during normal operation and can also minimize excess caused by integration during temperature transitions. Therefore, in Figure 49-9, the solution 500 heater system operates effectively and within desired specifications, and the actual temperature of the heater tray 515, the actual temperature of the button detector 517, and a temperature Probe 552 converge at the fluid set point temperature 550 after approximately 30 minutes.
In sum, the disclosed temperature controller can achieve good thermal control of a two-component system, in which the mass of the first component varies over time, and in which the second component includes a heater or cooler, and both components are in an isolated volume. This thermal control can be achieved by controlling the equilibrium temperature. The temperature controller determines the temperature of both components as well as the mass of the variable component. The temperature controller varies the heating or cooling of the second component to bring the equilibrium temperature to the desired set point temperature. The equilibrium temperature is the weighted average temperature of the thermal capacitance of the two components. The controller can use a proportional feedback loop to control the equilibrium temperature.
284
The temperature controller can also include an integral term that responds to the difference between the set point temperature and the temperature of the first component. The integral term can optionally be turned on when some or all of the following conditions are met:
• the rate of temperature change of the first component is low;
• the temperature of the first part is close to the set point temperature;
• the volume of the first part exceeds some minimum level;
• the control output signal is not saturated.
The temperature controller may also include a feed advance term that adds the set point temperature to the output of the proportional and integral terms.
In addition, the temperature controller may be the outer loop controller of a cascading temperature controller in which the outer loop controller includes at least one proportional control term over the equilibrium temperature and outputs a set point temperature for the indoor controller. The indoor controller controls the temperature of the first component with the heater or cooler elements at the set point temperature produced by the outdoor controller.
285
Universal Energy Supply
In accordance with one aspect of the disclosure, the APD system may include a universal power supply that converts line voltage to one or more DC voltage levels for some or all of the electromechanical and electronic elements in cycler 14, and provides AC power to the electric heater for heater tray 142. The electro-mechanical elements in cycler 14 can include pneumatic valves, electric motors, and pneumatic pumps. The electronics in cycler 14 may include control system 16, display 324, and detectors. AC power is supplied to a heater controller to control the temperature of the solution in the heater bag 22 or heater tray 142 to a desired set point before supplying the solution to the user / patient. Universal Power Supply changes the configuration of two (or more) heater elements to accommodate two ranges of AC line voltages: for example, a first range of 110 + 10 volts rms; and a second interval of 220 + 20 volts rms. This provision is intended to accommodate the use of the APD 10 system in many different countries. During the start of a therapy session, the APD cycler 14 fills the heater bag 22 with solution from the solution containers 20 connected via a heater bag line 26. In an alternative embodiment, a pre-filled bag of solution on a heater tray 142 at the start of therapy.
286
PWM Heater Circuit
The heater controller on the APD cycler modulates the electrical power supplied to the heater elements attached to the heater tray 142. The APD cycler can be used in various locations around the world and can be plugged into AC outlets that supply power from 100 to 230 volts rms. The heater controller and circuits can be adapted to the variety of AC voltages while continuing to supply sufficient heater power and without blowing fuses or damaging heater elements in many ways.
One embodiment of a heater circuit is presented in Figure 49-10, where a 2005 pulse width modulator (PWM) based circuit controls the temperature of the heater tray 142 with a pulse width modulated element ( PWM) 2010 connected between a lead from AC jacks 2040 and heater element 2000. Controller 2035 is operably connected to relay 2030 and PWM element 2010. Controller 2035 monitors heater operation by interrogating voltage detector 2020 and temperature detector 2007. Controller 2035 can modulate the amount of power supplied to heater 2000 via a signal to the 2010 PWM element. The PWM element or modulated with Pulse width closes for some fraction of a fixed period between 0 and 100%. When the PWM 2010 element closes 0% of the time, no electrical energy flows to heater 2000. The heater is continuously connected to the AC 2040 socket
287 when the PWM element is 100% closed. Controller 2035 can modulate the amount of energy dissipated by heater 2000 by setting the PWM 2010 element in a range of values between 0 and 100%, inclusive.
Elements of PWM 2010 turn large current flows on and off multiple times per second. The elements of PWM 2010 are typically some form of solid state relay (SSR). SSRs for AC voltage typically include an activation circuit that controls the power switch. The trigger circuit may be, for example, a reed relay, a transformer, or an optical coupler. The power switch can be a Silicon Control Rectifier (SCR) or TRIAC. SCR or TRIAC are also referred to as thyristors. An example of an SSR is the MCX240D5® by Crydom Inc.
In one example, controller 2035 can modulate the value of the PWM element to control the temperature of heater tray 142 as measured by temperature detector 2007. In another example, controller 2035 can modulate the value of the element of PWM to control the temperature of the fluid in the heater bag 22. In another example, the 2935 controller can control the 2010 PWM element to provide a fixed heater power schedule. Controller 2035 can command a safety relay 2030 that opens the heater circuit and stops the flow of electrical energy to heater 2000. Safety relay 2030 can be controlled by a separate controller (not
288 sample) to provide a safety circuit independent of the 2035 controller.
The 2005 PWM-based circuit may include a 2020 voltage sensing element that provides a signal to the 2035 controller indicative of the voltage over the AC outlet 2040. In one example, the 2020 voltage sensing element can measure the AC potential across AC outlet 2040. In another example, voltage sensing element 2020 can measure current flow through heater 2000. Controller 2035 can calculate the voltage across the AC outlet from a known resistance of the heater element 2000, the signal from the PWM element 2010, and the measured current.
The PWM 2005 based circuit can vary the maximum allowable duty cycle of the PWM 2010 element to accommodate different AC tap voltages. Heater element 2000 may be designed to provide the maximum power required with the lowest possible AC voltage. The controller can vary the duty cycle of the PWM 2010 element to provide a constant maximum heater power for a range of voltages at the AC outlet. For example, the voltage supplied to heater 2000 from a 110 volt AC line can be supplied in a 100% duty cycle, and the same amount of electrical power can be supplied to heater 2000 from a 220 volt AC line. if the PWM 2010 item is set to 25%. PWM 2010 element duty cycle can be further reduced
289 below the maximum value to control the temperature of the heater tray 142.
The temperature of the heater element 2000 and of the heater tray 142 can be controlled by the average energy of the heater for a time constant that is a function of the thermal mass of the heater element and tray. The average power of the heater can be calculated from the resistance of the heater, which is relatively constant, and the rms voltage across the heater element 2000. In a practical sized heater, the PWM frequency is much faster than the heater system time constant, so the effective voltage across the heater element is simply the PWM duty cycle multiplied by the rms voltage.
A method for controlling the circuit heater pan temperature in Figure 49-10 can direct the 2035 controller to establish a maximum PWM duty cycle based on the voltage measured in 2020. The maximum duty cycle can be calculated at from the desired maximum heater power, the known resistance of the heater element 2000 and the measured voltage. A possible example of the calculation is:
PWMmax = (Pmax * ^ heater)<sup>0 5</sup> ¡V<sub>rm</sub>s where PWM<sub>m</sub>áx is the maximum allowable PWM duty cycle, Pmax is the maximum power of the heater, Rheater is the nominal resistance of the heater element 2000, and V<sub>rm</sub>s is the voltage
290 supplied measured by the 2020 Voltage Detector. Another example of the calculation is:
PWMmax = PmAx / (I<sup>2</sup> * ^ heater) where I is the current flow through the heater when the voltage is applied. Controller 2035, after setting the maximum PWM duty cycle, varies the PWM duty cycle of the 2010 PWM element to monitor the heater pan 142 temperature measured by a 2007 temperature detector. The controller can control the PWM element to achieve a desired temperature in many ways, including, for example, a PID feedback loop or a Pl feedback system.
In an alternate method and configuration, the PWM 2005 circuit does not include the 2020 voltage detector. In this alternate method, the 2035 controller varies the PWM duty cycle of the 2010 PWM element to achieve the desired heater pan temperature. measured by means of the 2007 temperature detector. The 2035 controller starts the warm-up cycle at a minimum PWM duty cycle and increases the PWM duty cycle until the temperature sensor reports the desired temperature to the 2035 controller. The rate of increase in the PWM speed may be limited or controlled to prevent excessive currents that could blow off and blow 2050 fuses. The 2035 controller can alternatively use small gains in a feedback calculation to limit the rate of increase of the duty cycle
291 PWM. Alternatively, the controller may use a feed advance control to limit the rate of increase in the PWM duty cycle.
Dual Voltage Heater Circuit
An example of a 2012 dual voltage heater circuit that changes the heater resistance is shown as a schematic block diagram in Figure 49-11. The block diagram in Figure 49-11 presents an example of a 2012 dual voltage heater circuit to provide approximately constant heater power for the two standard AC voltages of 110 and 220 volts rms. The 2012 dual voltage heater circuit limits the maximum current flow by reconfiguring the heater and thus is less sensitive to software errors by setting the PWM element duty cycle as in the 2005 circuit. The 2012 circuit decreases the maximum current flow. through the PWM 2010 element that enables smaller and less expensive SSRs. The selection of the heater configuration in the 2012 circuit is separate from the modulation of the heater to improve control and reliability. The elements of PWM 2010A, 2010B that modulate heater power are typically SSRs, which typically stay closed, thus providing maximum power. The 2014 heater select relay may be an electromechanical relay, which, while less than ideal for high cycle applications, may typically be preferred for
292 Critical safety circuits, due in part to the tendency of electromechanical relays to stay open. Selection of the heater configuration by the processor allows more control of the heater configuration.
In the event that the AC outlet voltage fluctuates, perhaps due to a blackout, the controller preferably keeps the heater setting constant. In contrast, a circuit that automatically changes the heater setting based on the instantaneous voltage could fluctuate between heater settings. This can result in high current flows if the circuit does not respond fast enough for the line voltage to return to its original level from a temporarily lower level. In one mode, the processor receives input from the user or patient when selecting the heater setting (parallel or serial), and the 2012 dual voltage heater circuit does not automatically switch between settings in response to fluctuating line voltage. In another mode, the processor measures the current flow in the series setting (i.e. the upper resistance setting) with full power, selects an appropriate heater setting for the AC outlet voltage at the start of therapy , and does not change the settings for the duration of therapy.
The 2012 dual voltage heater circuit can comprise two heater elements 2001, 2002 that can be connected in parallel or in series with each other to provide the same heater power for two
293 Different voltages at the AC 2040 outlet. Each heater element 2001, 2002 may comprise one or more heater sub-elements. The electrical resistance of the heater elements 2001, 2002 is preferably approximately equal. Controller 2035 can receive a current sense signal 2022 and control heater selection relay 2014 to connect heater elements 2001, 2002 either in series or in parallel. Controller 2035 can change the electrical arrangement of the two heater elements to limit the flow of current resulting from different AC outlet voltages. An example of a 2022 current sense is an AC-1005 current sense transformer made by Acmé Electñc.
The energy in the heater elements 2001, 2002 can be further modulated by means of the PWM 2010A, 2010B elements controlled by the 2035 controller to achieve a desired temperature measured by the 2007 temperature detector, or to achieve other control goals as described above. The elements of PWM 2010A, 2010B can be solid state relays like MCX240D5® by Crydom Inc. Safety relay 2030 may be configured to disconnect heater elements 2001, 2002 from AC outlet 2040. Safety relay 2030 may be controlled by controller 2035 or other processor or safe circuit (not shown).
The 2030 Safety Relay and 2014 Heater Select Relay can be in solid state or electromechanical relays. In a
294 Preferred embodiment, Safety Relay 2030 and / or Heater Selection Relay 2014 are electromechanical relays. An example of an electromechanical relay is a G2AL-24-DC12 relay made by OMRON ELECTRONIC COMPONENTS and other manufacturers. Electromechanical relays are often preferred for safety critical circuits as they are considered more robust and more reliable than solid state relays, and have a tendency to stay open. They may also be less susceptible to various flaws in the driver software.
In one example, the 2014 heater select relay comprises a dual pole double release relay, in which the outputs connect to the heater elements 2001, 2002. The 2014 heater select relay, in the non-energized state, connects heater elements 2001, 2002 in series so that current flows through one element and then the other. The serial configuration can be accomplished, in an example circuit, by the following: connecting the first end of the 2001 heater element to the L1 2041 circuit via the PWM 2010A element; connect the joined ends of the heater elements 2001, 2002 to an open circuit via the first pole 2014A; connect the second end of the 2002 heater element to the L2 2042 circuit via the second post 2014B. In an energized state, the heater select relay 2014 connects the heater elements in parallel so that approximately half of the current flows through each PWM and the heater element. Parallel configuration can be accomplished in
295 the same example circuit by means of the following: connect the first end of the 2001 heater element to the L1 2041 circuit via the PWM 2010A element, connect the second end of the 2002 heater element to the L1 2041 circuit via the PWM element 2010B; connect the joined elements of the heater elements 2001, 2002 to the L2 circuit 2042 via the first post 2014A. The preferred circuit connects the 2001, 2002 heater elements in series in the unlit condition, as it is a safer configuration because the resulting superior resistance will limit current flows and avoid overloading the 2050 fuses, or overheating the 2001 heating elements , 2002 if connected to a higher voltage AC outlet.
Another example of a heater circuit 2112 that changes the effective resistance of the heater by changing the heater configuration is shown in Figure 49-12 as a schematic block diagram. The 2112 heater circuit is similar to the 2012 heater circuit (shown in Figure 49-11) except that the 2112 heater circuit provides better protection against current leakage in the event that the L1 and L2 circuits are reversed in the wall contact. Reversal of the L1 and L2 power circuits is possible if the power was improperly wired in the building supplying power to the heater circuit. Wiring in a residential building may not be as reliable as that of a hospital, where the entire electrical system is installed and maintained by qualified personnel.
296
The electrical components and connections between the PWM elements 2010A, 2010B, the L1 2041 nominal circuit, the 2001, 2002 heater elements, the 2014 heater selection relay, and the L2 2042 nominal circuit in the 2112 heater circuit are arranged to minimize leakage current regardless of the polarity of the wall contact. In the non-energized state as shown in Figure 49-12, the 2014 heater select relay connects the 2001, 2002 heater elements in series with the 2010A PWM element. A possible circuit connecting the heater elements in series includes: the first end of the heater element 2001 connected to the L1 circuit 2041 via the PWM element 2010A; the second end of the heater element 2001 connected to the first end of the heater element 2002 via the first pole 2014A, an L1 2014C and the second pole 2014B; and the second end of the heater element 2002 connected to the L2 circuit 2042 via the PWM element 2010B. In the energized state, heater elements 2001, 2002 and PWM elements 2010A, 2010B are connected in parallel. In an energized state, the heater select relay 2014 connects the heater elements in circuit 2122 in parallel so that approximately half the current flows through each PWM and the heater element. A possible circuit to connect the two heater and PWM elements in parallel includes: the first end of the 2001 heater element connected to the L1 2041 circuit via the PWM 2010A element; the second end of the 2001 heater element connected
297 via first post 2014A to circuit L2; the first end of heater element 2002 is connected to circuit L1 2041 via second post 2014B; the second end of the heater element 2002 is connected to the L2 circuit 2042 via the PWM element 2010B. The 2030 safety relay is located on the L2 2042 circuit and creates a failsafe condition with no current flow opening if a fault occurs. The control of the safety relay is described later. Controller 2035 controls heater settings to limit current flow measured by current sense 2022 to levels below the current rating for 2050 fuses, heater elements 2001, 2002, PWM elements 2010A, 2010B and limits the total energy of the heater. Controller 2035 varies the duty cycle of PWM elements 2010A, 2010B to control heater tray temperature 142 measured by detector 2007.
Implementation of the Dual Voltage Heater Circuit
A circuit diagram 2212 of one embodiment of the present invention is shown in Figure 49-13, which is equivalent to the 2012 heater circuit in Figure 49-11. In circuit 2212, the heater elements 2001, 2002 are connected in series via the 2014 heater select relay when the 2014D relay coil is not energized. Controller (not shown) connects heater elements 2001, 2002 and PWM elements 2010A, 2010B in parallel
298 supplying a signal at node 2224, which closes transistor switch 2224A, and energizing the relay coil using Vs DC 2214 power. The controller modulates the power from the heater by varying the duty cycle of the elements of PWM 2010A, 2010B to via a signal at node 2220 and energized with V 2210 supply. Current flow is measured in current direction 2022. Safety relay 2030 is normally open. The 2030 safety relay can be controlled by means of an FPGA board that is separate from the controller. The FPGA board monitors APD cycler operation, including heater pan temperature and current direction, and many other parameters. The FPGA board can open the relay by removing the signal at node 2228. The coil of the 2030D safety relay is energized by V 2218 safety.
In one example, the voltage supplying supply V 2210, Vs 2214, safety V 2218 may be the same voltage source. In another example, each voltage source is controllable to provide additional operation control of the heater circuit for added safety. In one example, V 2218 security can be controlled by multiple processors in APD Cycler 14. If either processor detects an error and fails, then safety circuit V opens, Safety Relay 2030 opens, and heater power turns off.
Dual Voltage Heater Circuit Operation
299
The heater circuit is operated to provide adequate heater power without allowing harmful currents to flow through the heater elements 2001, 2002, or 2050 fuses. Heater circuit 2212 may be configured before therapies are run on the APD 14 cycler and do not change during operation regardless of voltage changes at the AC outlet. Control system 16 (in Figure 45) initiates heater control circuit 2212 with heater selection relay 2014 non-energized, so that heater elements are connected in series to minimize current. As a part of the startup processes, the software on the automation computer 300 can run a current flow test of the heaters by commanding the elements of PWM 2010A, 2010B to a 100% duty cycle and the resulting test current it is measured by current sense 2022 and communicates with automation computer 300. The duty cycle of PWM 2010 elements can be reset to zero after the current flow test.
In an example method, automation computer 300 evaluates the measured test current against a predetermined value. If the measured test current is above a given value, the automation computer 300 will proceed with the ADP cycler startup process. If the measured test current value is below the same given value, then automation computer 300 will energize the heater safety relay to reconfigure the elements
300 heater 2001, 2002 in parallel. The current flow test is repeated and if the new measured test current is above the predetermined value, the automation computer 300 will proceed with the ADP cycler startup procedure. If the measured test current of the current flow test with parallel heater elements is below or above the predetermined value, the automation computer 300 will report an error to the user interface computer 302.
Alternatively, automation computer 300 can calculate a test voltage based on the measured test current and the configuration of the heater element. If the test voltage is in the Range of 180 to 250 volts rms, then automation computer 300 will proceed with the ADP cycler startup procedure. If the test voltage is in the range of 90 to 130 V rms, then automation computer 300 will energize the heater select relay to reconfigure heater elements 2001, 2002 in parallel, repeat the current flow test, and recalculate the test voltage. If the test voltage is in the range of 90 to 130 V rms, the automation computer 300 will proceed with the ADP cycler startup procedure, otherwise the automation computer 300 will report an error to the user interface computer 302 .
In another example method, automation computer 300 compares the measured test current with the heater elements
301 configured in series with a low series range and a high series range of current values. The low series interval is consistent with a low AC voltage flowing through the series arranged heater elements. The high series interval is consistent with a high AC voltage flowing through the series arranged heater elements. In an exemplary embodiment, the low AC voltage includes rms values from 100 to 130 volts, while the high AC voltage includes rms values from 200 to 250 volts.
If the measured test current is outside the low range and the high range, then the automation computer 300 can determine that the heater circuit is faulty and signal an error to the user interface computer 302. If the measured test current It is within the high range, the heater setting is left unchanged, and the APD 14 cycler startup can continue. If the measured test current is within the low range and the heater elements are arranged in series, then automation computer 300 can reconfigure the heater elements 2001,2002 to a parallel arrangement by energizing the 2014 heater safety relay through of a signal at node 2224. Automation computer 300 can control the 2014 heater safety relay via a command sent to hardware interface 310 which in turn provides the signal to drive the 2014 heater selection relay.
Automation computer 300 can repeat test
302 current flow after reconfiguring the heater elements in a parallel arrangement by again commanding the PWM 2010A elements to a 100% duty cycle and measuring the current flow with the current direction 2022. The Measured test can be evaluated against the parallel low range of current values. If the measured test current is within the parallel low range values, proceed with the ADP cycler startup procedure. If the newly measured test current is outside the parallel low range values, then automation computer 300 will report an error to user interface computer 302.
The FPGA controller implemented in hardware interface 310 can be programmed to command safety relay 2030 to open via a signal at node 2228 while the 2014 heater select relay is changed. The 2030 safety relay can be opened each time the 2014 safety relay is opened or closed to prevent a short circuit from one pole to the other within the 2014 heater selection relay.
Dual Voltage Heater Circuit Operation with User Input
In an alternative embodiment, automation computer 300 may require user intervention before reconfiguring heater elements 2001, 2002. Requesting user input
303 provides a valuable security feature of an embodiment of the present invention. Figure 49-14 shows a logical flow diagram illustrating a method 2240 for including the user in setting the heater elements appropriately for the available AC voltage. At step 2241, control system 16 (in Figure 45) initiates heater control circuit 2212 (Figure 49-13) with heater selection relay 2014 not energized, so that heater elements are connected in series to minimize current. In configuration 2242, automation computer 300 commands the elements of PWM 2010A, 2010B to a 100% duty cycle and the current is measured by current sense 2022 and the measured test current is communicated to the processor. The duty cycle of PWM 2010 elements can be reset to zero after the test current is measured. In step 2244, automation computer 300 compares the measured test current with a first interval. In step 2245, if the measured test current is within the first range, then the heater setting is correct and the APD operation proceeds in step 2254. In an alternative embodiment, method 2240 includes step 2245A where user interface computer 302 prompts the user to confirm the AC outlet voltage determined by automation computer 300 from the measured test current and heater configuration before proceeding from step 2245. If the user does not confirm the AC voltage level, method 2240 will proceed to step 2252 and display an error.
304
In step 2246, if the measured current is outside the second range, then method 2240 shows an error in step 2252, otherwise method 2240 proceeds to step 2247. In step 2247, if the user confirms the voltage under AC, then the heater setting will be changed in step 2248, otherwise method 2240 shows an error in step 2252. In step 2248, automation computer 300 reconfigures heater elements 2001, 2002 to a parallel arrangement by energizing heater selection relay 2014 through a signal at node 2224. After reconfiguring heater elements in step 2248, method 2240 retests the heater in step 2242 and continues through the logical flow diagram of method 2240.
In an alternative embodiment, a user or patient can store the AC voltage as high or low in the memory of control system 16 so that automation computer 300 does not need to question the user or patient at each treatment to confirm the supply voltage. AC. Figure 49-15 shows a logical flow diagram illustrating a method 2260 where the AC voltage value is stored in the memory of control system 16. Steps 2241 to 2246 are the same as in method 2240 described above. At step 2249, the memory is queried for the stored AC voltage value. If the stored AC voltage value is low, then method 2260 proceeds to step 2248 and reconfigures the heater elements in a parallel arrangement. If the stored AC voltage is high or non-zero, then the
305 User interface 302 may prompt the user to confirm a low AC outlet voltage. If a user confirms the low AC voltage, then method 2260 proceeds to step 2248 and reconfigures the heater elements in a parallel arrangement. Step 2248 may also include setting the stored AC voltage as low. After reconfiguring the heater elements in step 2248, method 2260 retests the heater in step 2242 and continues through the method 2260 logical flowchart.
In one example, method 2260 may include a step 2245A that reads from memory or calculates the test voltage from the measured test current and heater settings, and then causes user interface computer 302 to prompt the user to confirm the test voltage. The method may include a step between 2245 and 2246, where if the heater has been reconfigured to a parallel arrangement and the current is not within the high range, then the method proceeds to step 2252 and disables the APD 14 cycler.
Methods 2240 and 2260 can evaluate the measured test current using many different methods. A preferred method is described above and alternative examples are as described below. The first interval in step 2245 may be a range of current levels that would provide the desired maximum amount of heater power for the heater element current setting. Alternate step 2245 can calculate a test voltage at
306 from the measured test current and heater element configuration and assess whether the test voltage is correct for the heater configuration: approximately 110 V rms for parallel configuration and approximately 220 V rms for series configuration. Alternate step 2245 can test whether the measured test current is above a given predetermined value. The second interval in step 2246 may be a current value interval that corresponds to approximately 110 V rms in a series configuration. Alternate step 2246 can calculate a test voltage from the measured test current and heater element configuration and evaluate whether the test voltage is approximately 110 V rms for a series configuration. Alternatively, step 2246 can evaluate whether the measured test current is below a given predetermined value.
In another embodiment, the AC voltage value selected in method 2260 can be preloaded at the factory or distribution center based on the location of expected use. For example, the AC voltage value can be selected as low if the APD cycler is to be used in the US, Canada, or Japan. For another example, the AC voltage value can be selected as high if the APD cycler is to be used in Europe or Asia.
For machines intended to operate in a given region, this database can be as simple as a regional voltage being loaded into the machine at the factory, or being loaded by a technician.
307 during initial setup at an operating location. These regional AC voltage value prescriptions can be entered manually, using a memory device or similar device, a personal data key (PDK), a compact disc, a barcode reader, on the Internet network using a Ethernet or wireless connection or via any other obvious data transfer mechanism for the person skilled in the art. In other embodiments, the regional voltage sets can be accessible to the control system 16 and can be used to inform the user of the typical operating voltage in their area. In one embodiment, before accepting a user input in step 2247 to change the voltage from a previous setting, a user would be informed of the region's typical voltage; thus, a user unfamiliar with the value of regional voltages would only be asked to know their current location to provide a safeguard against voltage mismatch.
In another embodiment, the APD cycler 14 would be equipped with a mechanism to determine its current location, for example, a GPS tracker, an Ethernet connection, and a mechanism to determine the location of the connection, or a mode where the interface of User 302 can be used to enter the current location, such as a country or continent. In one embodiment, after starting a series heater configuration and running a current flow test, a user may simply be questioned about their present location; if the answer to that question coincides so much with the voltage associated with the
308 current measured as with the heater setting and typical voltage for that region, then treatment is allowed to proceed.
In an embodiment of the present invention, a manual switch (not shown), or alternatively a logic switch, is used to set the APD machine to the proper voltage and safe for use. Instantaneous voltage is measured and this measurement, either as the specific value or as a categorical descriptor, is presented to the user. The user must respond that the measured voltage is within the safe operating range for the machine as currently configured, or alternatively must respond by altering the configuration of the machine, before power is allowed to flow to the heater element. The configuration could be altered electronically, for example, via user interface computer 302, or could be done manually by moving a switch.
In another embodiment of the present invention, a rectifier converts any incoming alternating current (AC) into a single direct current (DC). The heater circuit would resemble the 2005 heater circuit in Figure 49-8, except that the 2020 voltage detector element is replaced with a universal DC supply that rectifies the AC voltage to a selected DC voltage. The electrical power supplied to the heater elements 2001, 2002 can be modulated by means of a PWM element in the rectifier or by means of a separate PWM 2030 element. The heater circuit may include a 2010 safety relay. The source DC voltage simple power
309 Allows the use of a heater configuration. The PWM element in this mode may comprise one or more IGBT switches or a MOSFET switch and related electrical hardware. In a preferred embodiment, the incoming alternating current would be converted to direct current in the range of 12V to 48V.
In another embodiment, the heater element 2000 may comprise a Positive Temperature Coefficient (PTC) element that self-limits the dissipated energy. The internal electrical resistance of a PTC element increases with temperature, so that the energy level is self-limiting. PTC heater elements are commercially available from companies like STEGO and are rated to run at voltages from 110 to 220 V rms. A heater circuit employing a PTC heating element would resemble the 2005 heater circuit with the 2020 voltage sensing element removed. The heater power would be controlled with the 2010 PWM element using a Triac.
Database Systems and User Interface
Database subsystem 346, also on a user interface computer 302, stores all data to and retrieves all data from databases used for internal machine storage, patient, prescription, user input and treatment history information. This provides a common access point when such information is needed by the system. The
310 The interface provided by the 346 database subsystem is used by various processes for their data storage needs. The 346 database subsystem also handles maintenance and backup of database files.
The Ul 338 screen view can invoke a therapy log question application to search the therapy history database. Using this application, which alternatively can be implemented as multiple applications, the user can graphically review their treatment history, their prescription and / or historical machine status information. The application transmits database questions to the 346 database subsystem. The application can be executed while the patient is dialyzing without preventing the safe operation of the machine.
The remote access application, which can be implemented as a single application or multiple applications, provides the functionality to export therapy data and machine diagnostics for analysis and / or deployment on remote systems. The therapy registration question application can be used to retrieve required information, and the data can be reformatted into a machine neutral format, such as XML, for transport. Formatted data can be carried externally by a memory storage device, direct network connection, or other external interface 348. Network connections can be initiated by the APD system, as required by the user.
311
Service interface 356 can be selected by the user when a therapy is not in progress. Service interface 356 may comprise one or more specialized applications that record test results and optionally generate a test report that can be uploaded, for example, to a diagnostic center. The media player 38, for example, can play audio and / or video to be presented to a user.
Pursuant to an exemplary implementation, the databases described above are implemented using SQLite®, a software library that implements a zero-configuration, transactional, serverless, self-contained SQL database engine.
The executive subsystem 332 implements two executive modules, the user interface computer (UIC) executive 352 on the user interface computer 302 and the automation computer (AC) executive 354 on the automation computer 300. Each executive is started by startup scripts that operate after the operating system is started and includes a list of processes that start. As executives go through their respective process lists, each process image is verified to ensure its integrity in the filing system before the process is launched. Executives monitor each child process to ensure each one starts as expected and continues to monitor child processes as they operate, for example, using Linux parent-child process notifications. When a process
312 As a child ends or falls, the executive restarts it (as in the case of Ul's view) or places the system in failsafe mode to ensure that the machine behaves in a safe manner. Executive processes are also responsible for the sharp shutdown of the operating system when the machine is turned off.
The executive processes communicate with each other allowing them to coordinate the startup and shutdown of the various application components. Status information is shared periodically between the two executives to support a watchdog role between processors. The executive subsystem 332 is responsible for enabling or disabling the secure line. When both the UIC 352 executive and AC 354 executive have enabled the safe line, the pump, heater, and valves can operate. Before enabling the lines, executives test each line independently to ensure proper operation. In addition, each executive monitors the status of the other secure line.
The UIC 352 executive and AC 354 executive work together to synchronize the time between the 352 user interface computer and the 300 automation computer. The time base is configured using a battery-backed real-time clock on the computer 302 user interface that is accessed at startup. The user interface computer 302 initializes the CPU of the automation computer 300 in the real time clock. After that, the operating system on each computer maintains its own internal time. Executives work
313 together to ensure sufficient maintenance by periodically performing power-on self-tests. An alert can be generated if a discrepancy between the time of the automation computer and the time of the user interface computer exceeds a given threshold.
Figure 47 shows the flow of information between various subsystems and processes of the APD system. As previously described, the Ul 360 model and 362 cycler controller operate on the automation computer. The user interface design separates the screen display, which is controlled by the Ul 338 view, from the screen-to-screen flow, which is controlled by the cycler controller 362, and the drop-down data items, which are controlled by the Ul 360 model. This allows the visual representation of the screen display to be changed without affecting the underlying therapy software. All therapy and context values are stored in the Ul 360 model, isolating the Ul 338 view from safety critical therapy functionality.
The Ul 360 model aggregates the information that describes the current state of the system and the patient, and maintains the information that can be displayed by the user interface. The Ul 360 model can update a state that is currently not visible or otherwise discernable to the operator. When the user navigates to the new screen, the Ul 360 model provides the information related to the new screen and its contents to Ul 338 view. The Ul 360 model exposes an interface that allows the Ul 338 view or some other process to ask for the
314 current user interface screen and content to display. The Ul 360 model therefore provides a common point where interfaces such as remote user interface and online support can obtain the status of the current operating system.
Cycler controller 362 handles changes to system status based on operator input, time, and therapy layer status. Acceptable changes are reflected in the Ul 360 model. The 362 cycler controller is implemented as a hierarchical state machine that coordinates therapy layer commands, therapy status, user requirements, and time regulated events, and provides control screen display via Ul 360 model upgrades. Cycler controller 362 also validates user input. If user input is allowed, new values related to user input are reflected back to the Ul 338 view using the Ul 360 model. Therapy process 368 acts as a server for the 362 cycler controller. Therapy commands from the 360 Cycler Controller are received by Therapy Process 368.
The Ul 338 view, which operates on the Ul 302 computer, controls the user interface display and responds to user input from the touch display. The Ul 368 view maintains local screen status tracking, but does not maintain machine status information. The state of the machine and displayed data values, unless they are half changed by the user, come from the Ul 360 model.
315 Ul 338 view ends and is restarted, displays the base screen for the current status with current data. The Ul 338 view determines what kind of screen the Ul 360 model will display, leaving the display presentation to Ul's view. All critical security aspects of the user interface are handled by the Ul model. 360 and 362 cycler controller.
Ul View 338 can load and run other applications 364 on user interface computer 302. These applications can perform non-controlling therapy tasks. Exemplary applications include the log viewer, service interface, and remote access applications. Ul's view 338 places those applications within a window controlled by Ul's view, which allows Ul's view to display status, error and alert screens as appropriate. Certain applications can be operated during active therapy. For example, the log viewer can operate during active therapy, while the service interface and remote access application generally do not. When an Ul 338 view application subserver is operating and user attention is required by therapy in progress, Ul 338 view may suspend the application and regain control of the display and input functions. Suspended application can be resumed or can be aborted by Ul 338 view.
Figure 48 illustrates the operation of the therapy subsystem 340 described in connection with Figure 46. The therapy subsystem 340 is divided
316 Functionally in three procedures: therapy control, therapy calculation and solution management. This allows functional decomposition, ease of testing and ease of updates.
Therapy Control Module 370 uses the services of Therapy Calculation Module 372, Solution Management Module 374, and Machine Control Subsystem 342 (Figure 46) to accomplish its tasks. Responsibilities of the Therapy Control Module 370 include tracking fluid volume in the heater bag, tracking fluid volume in the patient, tracking patient drain volumes, and ultrafiltering, tracking and recording cycle volumes, tracking and register therapy volumes, organize the execution of dialysis therapy (drain-fill-residence), and control therapy preparation operations. Therapy Control Module 370 performs each phase of therapy as directed by Therapy Calculation Module 370.
Therapy Calculation Module 370 tracks and recalculates the drain-fill-residence cycles comprising peritoneal dialysis therapy. Using the patient's prescription, the therapy calculation module 372 calculates the number of cycles, the residence time, and the amount of solution required (the total therapy volume). As therapy proceeds, a subset of these values is recalculated, applying the actual elapsed time. Therapy calculation module 372 tracks the therapy sequence, passing the therapy phases and parameters to the therapy control module 370 when required.
317
The solution management module 370 maps the placement of solution supply bags, tracks the volume in each supply bag, commands the mixing of recipe-based solutions in the solution database, commands the transfer of the required volume of mixed or unmixed solution in the heater bag, and tracks the volume of available mixed solutions using the solution recipe and available bag volume.
Figure 49 shows a sequence diagram representing exemplary interactions of the therapy module processes described above during the initial replacement and dialysate portions of therapy. During the illustrative initial refill process 376, the therapy control module 370 searches for the solution ID and volume for the first fill of the therapy calculation module 372. The solution ID is passed to solution management module 374 with a request to fill the warmer bag with solution, in preparation for starting the patient line and the first patient fill. Solution management module 374 passes the request to machine control subsystem 342 to begin pumping the solution into the heater bag.
During illustrative dialysis process 378, therapy control module 370 runs one cycle (initial drain, fill, residence fill, and drain) in one time, sequencing these cycles under the control of therapy calculation module 372. During therapy , the 372 therapy calculation module is updated with the actual cycle time, so you can
318 recalculate the rest of the therapy if necessary.
In this example, the therapy calculation module 372 specifies the phase as "initial drain", and the therapy control module requests the machine control subsystem 342. The next phase specified by the therapy calculation module 372 it is "filled". The instruction is sent to the machine control subsystem 342. Therapy calculation module 372 is called once again by the therapy control module 370, which requests that the fluid be replenished in the heater bag during the fixation phase. Solution management module 374 is required by therapy control module 370 to fluid fill the heater bag as required by machine control subsystem 342. Processing continues with therapy control module 370 which requires therapy calculation module 372 to proceed to the next phase. This is repeated until there are no more phases, and the therapy is complete.
Pumping Monitor / Mathematical Repeater
The Pumping Monitor / Mathematical Repeater process is a software or function process that runs on the automation computer 300 separately from the security executive 354. The Pumping Monitor / Mathematical Repeater process is implemented as two threads or sub- separate functions that run independently. The mathematical repeater thread, referred to herein as the MR thread, confirms the result of the FMS calculation. The Pumping Monitor thread, referred to as
319 The PM wire monitors the net fluid and air flow through the relevant endpoints from the information provided in the Machine 342 process routine status messages. The relevant endpoints may include but are not limited to 5 potential bag spikes, heater bag, patient port, and drain port. The PM thread will also monitor the temperature of the heater tray via the IO Server process information. The PM thread will signal an alarm to Security Executive 354 if the predefined limits for fluid flow, air flow, or temperature are exceeded.
The MR wire accepts the high speed pressure data and repeats the FMS calculation described above to recalculate the displaced fluid volume. The MR thread compares its recalculated fluid volume with the volume calculated through Machine 342 process and sends a message to the security executive. In another example, the MR thread declares an error condition if the two fluid volume values do not match.
The PM wire monitors various aspects of the pumping process as a safety check on the operation of cycler 14. The PM wire will declare an invalid pumping operation error condition if Hardware Interface 310 reports open valves that do not match the pumping action commanded by the Machine 342 subsystem. An example of an invalid valve condition would be if any port valve 186, 184 (Figure 6) were open while the pump is in idle mode. The condition of the valves in the cassette is
320 Maps to the state of the corresponding pneumatic valves 2710, which are powered by the hardware interface 310. Another example of an invalid valve condition would be a valve port 184, 186 that is open and does not correspond to the specified source of fluid sink.
The PM wire will declare an error condition if excess fluid is pumped to the patient while the heater button temperature sensor 506 reports less than a given temperature. In a preferred embodiment, the PM wire will declare an error condition if more than 50 ml of fluid is pumped into the patient while the button temperature is less than 32 ° C.
The PM wire will maintain a numerical accumulator of the amount of fluid pumped to the patient. If the total volume of fluid pumped to the patient exceeds a specified amount, the PM wire will declare an error. The specified quantity can be defined in the prescribing information and can include an additional volume equal to a chamber volume or approximately 23 ml.
The PM wire will maintain a numerical accumulator of the amount of air measured in the pumping chamber by means of the FMS method for the air taken from each bag. If the total amount of air in any bag exceeds the maximum allowable volume of air for that bag, then the PM thread will report an error. In a preferred embodiment, the maximum allowable air volume for the heater bag is 350 ml and the maximum allowable air volume for a supply bag is 200 ml. A
321 A large volume of air in a bag indicates that it may contain a leak into the atmosphere. The maximum volume of air allowed for the heater bag may be greater to compensate for degassing when the fluid is heated.
Alert / Alarm Features
Conditions or events in the APD system can trigger alerts and / or alarms that are logged, displayed to a user, or both. These alerts and alarms are a user interface construct that resides in the user interface subsystem, and can be triggered by conditions that occur anywhere in the system. These conditions can be grouped into three categories: (1) system error conditions, (2) therapy conditions, and (3) system operating conditions.
"System error conditions" refers to errors detected in software, memory, or other aspects of the APD system processors. Those errors require the reliability of the system in question and can be considered "unrecoverable". System error conditions cause an alarm to be displayed or to be done in another way known to the user. The alarm can also be logged. Since the integrity of the system cannot be guaranteed in the event of a system error condition, the system can enter a failsafe mode in which the security line described here is disabled.
322
Each subsystem described in connection with Figure 46 is responsible for detecting its own system errors. System errors between subsystems are monitored by user interface computer executive 352 and automation computer executive 354. When a system error originates from a process that is performed on user interface computer 302 , the process that reports the system error ends. If the Ul 338 screen view subsystem is terminated, the user interface computer executive 352 attempts to restore it, for example, up to a maximum of three times. If it fails to restore the Ul 338 screen view and therapy is in progress, the 352 user interface computer executive transitions the machine to a failsafe mode.
When a system error originates from a process that takes place in automation computer 300, the process ends. Automation computer executive 354 detects that the process has ended and transitions to a safe state if a therapy is in progress.
When a system error is reported, an attempt is made to inform the user, for example with visual and / or audio feedback, as well as to record the error in a database. System error handling is encapsulated in executive subsystem 332 to ensure uniform handling of unrecoverable events. The UIC 352 executive and AC 354 executive executive process monitors each other as
323 So if one executive process fails during therapy, the other executive transitions from the machine to a safe state.
"Therapy conditions" are caused by a state or variable associated with therapy that is outside the allowable limits. For example, a therapy condition may be caused by an out-of-limit detector reading. These conditions may be associated with an alert or alarm and then be logged. Alarms are critical events that generally require immediate action. Alarms can be prioritized, for example low, medium, or high, based on the severity of the condition. Alerts are less critical than alarms, and generally have no associated risk other than loss of therapy or discomfort. Alerts can be classified into one of three categories: message alerts, escalation alerts, and user alerts.
The responsibility for detecting therapy conditions that may cause an alarm or alert condition is shared between the Ul model and the therapy subsystems. The Ul 360 model subsystem (Figure 47) is responsible for detecting alarm and alert conditions before therapy and after therapy. Therapy subsystem 340 (Figure 46) is responsible for detecting alarm and alert conditions during therapy.
Responsibility for handling alerts or alarms associated with therapy conditions is also shared between the Ul model and therapy subsystems. Before therapy and after therapy, the
324 Ul 360 model subsystem is responsible for handling alarm or alert conditions. During a therapy session, therapy subsystem 340 is responsible for handling the alarm or alert condition and notifying the Ul model subsystem that an alarm or alert condition exists. The Ul 360 Model Subsystem is responsible for escalation alerts, and for coordinating with the Ul 338 Vision Subsystems to provide the user with visual and / or audio feedback when an alarm or alert condition is detected.
"System operating conditions" do not have an alert or alarm associated with them. Those conditions are simply recorded to provide a record of system operations. No need to provide auditory or visual feedback.
Actions that can be taken in response to the system error conditions, therapy conditions, or system operating conditions described above are implemented by the subsystem (or layer) that detected the condition, which sends the status to the higher subsystems. . The subsystem that detected the condition can record the condition and take care of any security considerations associated with the condition. These safety considerations may comprise any or a combination of the following: pause therapy and engage the occluder; clarify statuses and time regulators as necessary; disable the heater; complete therapy completely; deactivate the safety line to close the occluder, close the heater, and
325 remove power from valves; and prevent the cycler from performing therapy even after a power cycle to require that the system be returned to service. The Ul 334 subsystem may be responsible for conditions that can be cleared automatically (i.e. unencumbered conditions) and for user recoverable conditions that are locked and can only be cleared by user interaction.
Each condition can be defined in such a way that it contains certain information to allow the software to act in accordance with the severity of the condition. This information may comprise a numeric identifier, which can be used in combination with a lookup table to define priority; a descriptive name of the error (that is, a condition name); the subsystem that detected the condition; a description of what state or error triggers the condition; and flags for whether the condition implements one or more previously defined actions.
Conditions can be prioritized so that when multiple conditions occur, the highest priority condition can be managed first. This priority classification can be based on whether the condition stops the administration of therapy. When a condition that stops therapy occurs, this condition takes precedence when the state is relayed to the next higher subsystem. As described above, the subsystem that detects a condition handles the condition and sends status information to the previous subsystem. Based on received status information, the upper subsystem can
326 trigger a different condition that may have different actions and a different alert / alarm associated with it. Each subsystem implements any additional actions associated with the new action and passes the status information to the previous subsystem. In accordance with an illustrative implementation, the Ul subsystem only displays an alert / alarm at a given time. In this case, the Ul model classifies all active events by their priority and displays the alert / alarm that is associated with the highest priority event.
A priority can be assigned to an alarm based on the severity of the potential damage and the onset of that damage. Table 1 below shows an example of how priorities can be assigned in this way.
TABLE 1
START OF POTENTIAL DAMAGE
POTENTIAL FAILURE RESULT TO RESPOND TO THE
<td>CAUSE OF ALARM CONDITION</td><td>RIGH NOW</td><td>NOTICE</td><td>DELAYED</td>
<td>irreversible death or injury</td><td>High priority</td><td>High priority</td><td>medium priority</td>
<td>reversible injury</td><td>High priority</td><td>medium priority</td><td>low priority</td>
<td>minor discomfort or injury</td><td>medium priority</td><td>low priority</td><td>low priority or no alarm signal</td>
In the context of Table 1, the onset of potential damage refers to when an injury occurs and not when it manifests itself. Potential damage that has a start designated as “immediate” denotes damage that the
327 potential to develop within a period not usually sufficient for manual corrective action. Potential damage that has an onset designated as "soon" denotes damage that has the potential to develop within a period usually sufficient for manual corrective action. Potential damage that has an onset designated as “delayed” denotes damage that has the potential to develop within an unspecified time greater than that given under “notice”.
Figures 50 to 55 show illustrative screen views related to alarm alerts that can be delayed in a touch screen user interface. Figure 50 shows the first screen of an alarm, which includes a diagram 380 and a text 382 that instructs a user to close her transfer set. The display includes a 384 visual warning, and is also associated with an audio warning. The audio warning can be turned off by selecting the “audio off” option 386 on the touch screen. When the user has closed the transfer set, the user selects "confirm" 388 on the touch screen. Figure 51 shows a similar alarm screen that instructs a user to close their transfer set. In this case, an indication 390 that the drain is paused and an instruction 392 to select "end of treatment" are provided.
As described above, alerts generally have no associated risk other than loss of therapy or discomfort. Thus,
328 an alert may or may not cause therapy to be paused. Alerts can be "self-retrieving", such that if the event clears the alert it automatically clears, or "retrievable by the user" such that user interaction with the user interface is necessary to clear the alert . An audible alert message, which can have a volume that can be varied within certain limits, can be used to bring an alert to the attention of a user. Also, information or an instruction can be displayed to the user. Therefore said information or instruction can be displayed by the user, a self-decreasing feature of the user interface can be disabled during alerts.
To reduce the amount of user disturbance, alerts can be categorized into different types based on how important an alert is and how quickly user response is required. Three illustrative types of alerts are a "message alert," an "escalation alert," and a "user alert." These alerts have different characteristics based on how the information is visually presented to the user and how the audible message is used.
A "message alert" may appear at the top of the status screen and is used for informational purposes when no user interaction is required. Because no action needs to be taken to clear the alert, an audible message is generally not used to avoid disturbance, and possibly awakens the patient. However, an audible alert can optionally be presented. Figure 52 shows a
329 exemplary message alert. In particular, Figure 52 shows a low temperature message alert 394 that can be used to inform a user when the dialysate is below a desired temperature or desired range. In this case, a user does not need to take any action, but it is reported that the therapy will be delayed while the dialysate is heated. If the patient wants more information, the "view" option 396 can be selected on the touch screen. This causes additional alert related information 398 to appear on the screen, as shown in Figure 53. A message alert can also be used when there is a low flow event that the user is trying to correct. In this case, a message alert can be displayed until the low flow event is cleared to provide feedback to the user on whether the user fixed the problem.
An "escalation alert" is designed to prompt the user to take action in a non-unpleasant manner. During an escalation alert, a visual message can be displayed on the touch screen and an audible message can be presented (for example, once). After a given period, if the event that caused the alert is not cleared, a more emphatic audible message may be presented. If the event causing the alert is not cleared after an additional period, the alert is escalated to a "user alert". In accordance with an illustrative implementation of a user alert, a virtual message is displayed until the alert is cleared and an audible message, which can be silenced, is presented. The
330 Ul subsystem does not handle transition from escalation alert to user alert. Rather, the subsystem that triggered the original event will fire a new event associated with the user alert. Figure 54 shows a screen list that displays information regarding an escalation alert. This illustrative alert includes an on-screen alert message 400 and a message 402 that instructs the user to check the drain line for faults and clamps closed, as well as an audible message. The audible message can be continuous until it is silenced by the user. Figure 55 shows a screen view that includes a 404 "turn off audio" option that can be selected to mute the audio message. This alert can be used directly or as part of the escalation alert scheme.
Each alert / alarm is specified by: an alert / alarm code, which is a unique identifier for the alert / alarm; an alert / alarm name, which is a descriptive name of the alert / alarm; an alert / alarm type, comprising the type of alert or alarm level; an indication of whether an audible message is associated with the alert / alarm; an indication of whether the alert and associated event can be derived (or ignored) by the user; and an event code of the event or events that trigger the alert / alarm.
During alarms, escalation alerts, and user alerts, the event code (which may be different from the alert or alarm code, as described above) can be displayed on the screen so that the
331 User can read the code for service personnel if necessary. Alternatively or additionally a voice guidance system can be used, so that once connected to a remote call center, the system can voice relevant information about the system configuration, status and error code. The system may be connected to the remote call center through a network, telephone connection, or some other means.
An example of a condition detected by the therapy subsystem will be described later in connection with Figure 56. The condition results when the APD system is not located on a level surface, which is important for air management. More particularly, the condition results when a tilt detector detects that the APD system is tilted beyond a predetermined threshold, such as 35 °, from the horizontal plane. As described below, a recoverable user alert can be generated by the therapy subsystem if the tilt detector detects an angle with an absolute value greater than the predetermined threshold. To avoid nuisance alarms, the user can be given directions to level the APD system before therapy begins. The incline threshold may be lower during this pre-therapy period (eg 35 °). The user can also receive feedback regarding whether the problem is corrected.
When the tilt detector detects a tilt angle that exceeds a threshold value during therapy, machine subsystem 342 responds by stopping the pump in a manner similar to that of
332 detection of air in the pumping chamber. Therapy subsystem 340 inquires about the status and determines that the machine layer 342 has stopped pumping due to tilting. It also receives status information regarding the angle of the machine. At this point, therapy subsystem 340 generates a tilt condition, pauses therapy, and sends a command to machine subsystem 342 to pause pumping. This command triggers cleaning, such as taking measurements from the Fluid Measurement System (FMS) and closing the patient valve. Therapy subsystem 340 also initiates a time regulator and sends a self-healing tilt condition to the Ul 360 model, which sends the condition to the Ul 338 view. The Ul 338 view maps the condition to an escalation alert. . Therapy subsystem 340 continues to monitor the tilt detector reading and, if it falls below the threshold, clears the condition and restarts therapy. If the condition is not cleared before the time regulator expires, the therapy subsystem 340 triggers a recoverable "tilt-out" condition that exceeds the self-healing tilt condition. Send this condition to the Ul 360 model, which sends the condition to the Ul 368 view. The Ul 338 view maps the condition to a user alert. This condition cannot be cleared until an Ul subsystem therapy reset command is received (for example, user presses the resume button). If the tilt detector reading is below the threshold, therapy is resumed. If not below the threshold, the therapy layer triggers a new tilt condition
333 recoverable and starts the time controller.
Prioritized Audible Signals
The cycler can provide audible signals and voice guidance to the user to communicate a range of information that includes but is not limited to number selection, sound effects (button selection, action selection), machine condition, operating directions, alerts and alarms. Cycler controller 16 can cause a horn to announce audible signals and vocalizations from sound files stored in a memory on one or both computers 300, 302 in control system 16. Alternatively, vocalizations can be stored and produced by means of a specialized integrated voice circuit.
In some cases, the cycler may have multiple audible signals to announce simultaneously or sequentially in a very short time. Announcing multiple signals in a short period of time can overwhelm the user, resulting in annoyance or loss of critical security information. Cycler controller 16 can prioritize each audible signal and suppress lower priority signals to allow clear communication of higher priority audible signals. In one case, the audible signals are prioritized from the highest priority alarm signals to the lowest priority announcement in a sequence of numbers:
one. Alarms
2. Alerts
334
3. Sound effects
Four. Voice Guide
5. Announcement for a sequence of numbers.
Alarms and alerts were described above. Sound effects can confirm sounds to indicate that a button or choice has been selected. Sound effects can also announce or confirm a particular action being taken by the cycler. Voice guidance can include voice instructions for executing a particular procedure, access help, contacting a call center, and other directional instructions. Announcement for a sequence of numbers may include reading the user or the call center the number that the user had just typed, or may read the user the allowable values for the requested entry.
Audible Sleep Aid
Cycler 14 may include an option to play relaxing sounds at night to aid sleep. The reproduction of sounds such as rain, ocean waves, etc. it is referred to as sound therapy. Sleep sound therapy may provide some users with a superior tolerance to nighttime noises and mask or replace nighttime noise with more rhythmic and relaxing sounds that minimize disturbance during sleep. Sound therapy can help individuals suffering from hearing conditions like hyperacusis and tinnitus. The interface of
335 User 324 can provide the user with a menu to select sound types, volume levels, and duration, so that sound therapy can be played before and during the initial sleep period. Sound files can be stored in the memories of computers 300, 302 and played through the horn on cycler 14. In another example, the cycler may include an output jack for connecting external speakers. In another example, the sound and / or electronic files of the horn controller may be separated from either the automation computer 300 or the user interface computer 302. The sound files may include, but are not limited to, sounds of rain, thunderstorms, ocean waves, thunder, forest sounds, crickets, white noise, and pink noise (with varying amplitude and lower).
Battery Operation
The cycler may include a rechargeable lithium ion battery to be used as a replacement power source. At a minimum this battery helps ensure that the cycler does not turn off without alerting the user and saving the current status of the treatment. An energy management system can be implemented by means of the cycler when using battery power that is contingent on the amount of charge remaining in the battery. If the battery is sufficiently charged, the cycler can prevent blackouts or power outages from interfering with the termination of therapy. The cycler control circuit can measure the state of charge of the battery,
336 And it can correlate the battery charge level with operable states. This information can be obtained empirically through testing, and correlations between the battery charge level and the ability to operate the various subsystems can be stored in memory. The following functions may be associated with the battery charge level:
Level 4: Enough energy to carry out a cycle of therapy. Implemented if, for example, the battery charge level is equal to or greater than approximately 1,100 milliampere-hours.
Level 3: Enough energy to perform a user drain. Implemented if, for example, the battery charge level is equal to or greater than approximately 500 milliampere-hours.
Level 2: Enough energy to finish the therapy, display an alert and guide the user through the post-therapy breakdown. Implemented if, for example, the battery charge level is equal to or greater than approximately 300 milliampere-hours.
Level 1: Enough energy to finish therapy and display an alert. Implemented if, for example, the battery charge level is equal to or greater than approximately 200 milliampere-hours.
Level 0: There is not enough power to operate.
If there is sufficient charge in the battery (Level 4), the cycler will continue therapy unless the power cycle ends. This may not include replacing the heater bag or heating the solution. Therefore, if you are already in a filling phase, the cycler
337 You can continue therapy if the solution in the heater bag is in the appropriate temperature range and if there is enough solution in the heater bag. If the battery only has enough capacity to perform a 20 minute drain (Level 3), the cycler will alert the user, giving the user the option of either draining or terminating the treatment without draining. If the battery only has enough power to alert the user (Level 2) it will not give the user the drain option and the user will be guided through the post-therapy breakdown. If there is not enough power to guide the user through the breakdown (Level 1), the user will be asked to disconnect and then the cycler will shut down. At this battery level, the cycler may not have enough power to release the door, so the user may not be able to break down therapy. During startup, the cycler can assess the condition of the battery and alert the user if the battery has a fault or if the battery is insufficiently charged to at least alert the patient if the main power source is lost. The cycler can be programmed not to allow the user to start a treatment without the battery having sufficient capacity to provide an alert and guide the user through the post-therapy breakdown (Battery Level 2).
Another example of available battery charge levels and therapy choices or machine actions sets 4 battery charge levels and available therapy choices or machine actions:
Level 4:
If you have not started the filling process, then suspend the
338 operation until AC power is restored. The suspension is limited to 30 minutes.
If you have already started the filling process, then complete the cycle including the filling, fixing and draining processes.
The heater bag will not refill as there is no heating during battery operation.
Terminate therapy, and guide the user through the post-therapy breakdown including removal of dialysate delivery set 12a from cycler 14.
Level 3:
If filling or draining is in progress, then discontinue operation until AC power is restored. The suspension is limited to 30 minutes.
If you have already started the draining process, then complete the cycle.
The heater bag will not refill as there is no heating during battery operation.
Terminate therapy, and guide the user through the post-therapy breakdown including removal of dialysate delivery set 12a from cycler 14.
Level 2:
Terminate therapy, and guide the user through the post-therapy breakdown including removal of the
339 dialysate 12a of cycler 14.
Level 1:
Terminate therapy.
Level 0:
There is not enough power to operate.
An alert will be displayed to the user or patient at levels 1-4. Control system 16 can extend the operation of the cycler on battery power by decreasing the light intensity of display screen 324 after a given period of time. from the last touch on the screen. In another example, display screen 324 may reduce its light intensity after a given period of time from the appearance of the most recent message, alert, or warning. In one example, display screen 324 will decrease its light intensity 2 minutes after the last or most recent touch on the screen. Display screen 324 may include a message or symbol indicating the operation of battery power.
The electrical circuit that connects the battery to the pneumatic valves can include a regulated voltage boost converter that increases the variable battery voltage supplied to a consistent voltage. The supplied battery voltage may decrease while the battery is discharged. In one example, a fully charged Li-lon battery can supply 12.3 volts. The supplied voltage may decrease as the battery runs out of charge at a point as low as 9 volts when the
340 battery is completely discharged. Pneumatic valves may require a minimum voltage to fully reliably open. In one example, the minimum voltage to reliably open the valve can be 12 volts.
A regulated voltage boost converter can be placed between the battery and the valves to ensure that sufficient voltage reliably opens the valves while the battery is discharging. The regulated voltage boost converter will produce a regulated voltage higher than the variable battery voltage input. In one example, the voltage regulated pulse converter can be an integrated circuit like the TPS61175 made by Texas Instruments. A regulated voltage charge / boost converter can also be used between the battery and the valves. The charge / boost converter can supply a regulated voltage output from supplied voltages that are greater than, equal to, or less than the voltage input.
In one embodiment, the PWM duty cycle of valve controllers may vary with the measured battery voltage. The valves can be operated in a take-and-hold manner, where an initially higher voltage is applied to open the valve and then a lower voltage is applied to hold the valve in the desired condition. The PWM duty cycle for the clamp function can be inversely scaled with the measurement battery voltage to provide a consistent averaged voltage or current to the valves. The PWM Duty Cycle
341 It can be inversely scaled with the measured battery voltage for opening or higher voltage tap operation.
Screen Display
As previously discussed, the Ul 338 view subsystem (Figure 47) is responsible for presenting the interface to the user. The Ul view subsystem is a client of and interfaces with the Ul 360 model subsystem (Figure 47) that operates on the automation computer. For example, the Ul view subsystem communicates with the Ul model subsystem to determine which screen should be displayed to the user at a given time. Ul's view can include templates for screen views and can handle place-specific preparations like language, skin, audio language and culturally sensitive animations on the screen.
There are three basic types of events that occur in Ul's view subsystem. These are local screen events that are handled by individual screens, model events in which a screen event must propagate to Ul's model subsystem, and scrutinizing events that occur on a time regulator and query the Ul model subsystem for status. A local screen event only affects Ul's level of view. These events can be local screen transitions (for example, in the case of multiple screens for a single model state), updates to view values (for
342 example, location and language options), and requires playing media videos from a given screen (for example, animation prompts or voice messages). Model events occur when the Ul view subsystem must check with the Ul model subsystem to determine how to handle the event. Examples that fall into this category are confirming therapy parameters by pressing the "start therapy" button. These events are initiated by the Ul view subsystem, but are handled in the Ul model subsystem. The Ul model subsystem processes the event and returns a result to the Ul view subsystem. This result drives the internal state of the Ul's view subsystem. Scrutiny events occur when a time controller generates a time signal and Ul's model subsystem is scrutinized. In the event of a scrutinizing event, the current state of Ul's view subsystem is sent to Ul's model subsystem for evaluation. The Ul model subsystem evaluates the status information and responds with the desired state of the Ul view subsystem. This may constitute: (1) a state change, for example, if the major states of the Ul model subsystem and the Ul view subsystem are different, (2) a display update, for example, if the values of the Ul model subsystem change displayed values on screen, or (3) no state change, for example, if the state of the Ul model subsystem and the Ul view subsystem are identical. Figure 57 shows the illustrative Ul 338 view subsystem modules that perform the functions
343 described above.
As shown in Figure 57, the Ul model client module 406 is used to communicate events to the Ul model. This model 406 is also used to scan the Ul model for the current state. Within a response status message, the Ul model subsystem may span a time to be used to synchronize the clocks of the automation computer and the user interface computer.
Global slot module 408 provides a mechanism by which multiple callback routines (slots) can subscribe to be notified when given events (signals) occur. This is a "lot-to-lot" relationship, since one slot can be attached to many signals, and one signal can also be attached to many slots that have to be required for activation. The Global Slots Module 408 handles non-specific display slots, such as Ul model scrutinizing application level timers or depressing a button that occurs off-screen (for example, the voice message button) .
Screen list class 410 contains a list of all screens in the form of templates and data tables. A screen is made of a template and an associated data table that will be used to populate that screen. The template is a window with artifacts laid out in it in a generic way and with no content assigned to the artifacts. The data table includes records that describe the content used to populate the artifacts and
344 the state of the artifacts. An artifact status can be verified or unverified (in the case of a register box style artifact), visible or hidden, or enabled or disabled. The data table can also describe the action that occurs as a result of pressing a button. For example, a button in window 'A' derived from template Ί 'could send an event to Ul's model, while the same button in window' B 'also derived from template Ί' could simply cause a transition from local display without propagating the event to the Ul model. Data tables can also contain an index in the context sensitive help system.
Screen list class 410 sends Ul model data to the intended screen, selects the passed data on the appropriate Ul model screen, and displays the screen. Screen list class 410 selects which screen to display based on two factors: the state reported by Ul's model and the internal state of Ul's view. In some cases, the Ul model can only form the Ul view that is allowed to display any screen within a category. For example, the model may report that the machine is unloaded (for example, no therapy has been started or the start phase has not yet occurred). In this case, it is not necessary to confer with the Ul model when the user progresses from the menu to its submenu. To track the change, Ul View will store the current screen locally. This local sequencing of screens is handled by the table entries described above. The
3. 4. 5 table entry lists the actions that the respective buttons will initiate when pressed.
The language administrator class 412 is responsible for inventorying and managing translations. A checksum can be performed on the list of installed languages to alert Ul's view if any of the translations is corrupted and / or missing. Any class that wants a translated string asks the language administrator class 412 to do it. Translations can be managed via a library (eg Qt®). Preferably, translations are required as close as possible to the time of completion. For this purpose, most screen template member access methods require a translation immediately before passing it to the artifact for completion.
A skin comprises a style sheet and images that determine the "display and feel" of the user interface. The style sheet controls things such as types, colors, and what images an artifact will use to display its various states (normal, oppressed, disabled, etc.). Any deployed artifact may have its appearance altered by a skin change. The skin manager module 414 is responsible for informing the list of screens and for extension the screen artifacts, which style sheet and skin graphics should be displayed. The skin manager module 414 also includes any animated files that the application may wish to display. In a skin change event, the
346 skin manager will update the images and style sheet in the working set directory with the appropriate set, which is retrieved from the file.
The 416 video manager module is responsible for playing appropriate local video given a request to display a particular video. In a local change event, the video manager will update the videos and animations in the working set directory with the appropriate set of a file. The video manager will also play videos that have audio attached in the audio manager module 418. When playing these videos, the video management module 416 will make the appropriate request to the audio manager module 418 to play the record that belongs to the originally required video.
Similarly, the audio manager module 418 is responsible for playing audio appropriate to the location given a request to play a particular audio. In a local change event, the audio manager will update the audios in the working set directory with the appropriate set of a file. The Audio Manager Module 418 handles the audio initiated by Ul's view. This includes mixes for animations and sounds for voice messages.
The database client module 420 is used to communicate with the database administrator process, which manages the interface between the Ul view subsystem and the database server 366 (Figure 47). Ul's view uses this interface to store and retrieve
347 tasks, and to supplement therapy record with user-provided responses to questions about variables (eg, weight and blood pressure).
The help manager module 422 is used to manage the context sensitive help system. Each page in a screen list that features a help button can include an index in the context-sensitive help system. This index is used so that the help administrator can display the help screen associated with a page. The help screen can include text, images, audio, and video.
The ID 424 self-administrator is required during pre-therapy preparation. This module is responsible for capturing an image (for example, a photographic image) of a solution bag code (for example, a data matrix code). The extracted image data is then sent to the machine control subsystem to be used by the therapy subsystem to identify the contents of a solution bag, along with any other information (eg origin) included in the code. .
Using the modules described above, the Ul 338 view subsystem causes screen views to be displayed to the user via the user interface (for example, screen 324 of Figure 45). Figures 58 to 64 show exemplary screen views that can be interpreted using the Ul view subsystem. These screen views
348 They illustrate, for example, illustrative input mechanisms, display formats, screen transitions, icons, and strokes. Although the displayed screens are generally displayed during or before therapy, aspects of the screen views can be used for different input and output functions than those shown.
The screen shown in Figure 58 is an initial view that provides the user with the option of selecting between "start therapy" 426, start the specified therapy 428 or "values" 430 to change values. Icons 432 and 434 are respectively provided to adjust audio and brightness levels and an information cone 436 is provided to allow the user to request more information. These icons may appear on other screens in a similar way.
Figure 59 shows the status screen that provides information on the status of therapy. In particular, the display indicates the type of therapy being performed 438, the estimated completion time 440, and the number of current fill cycle and total number of fill cycles 442. The completion percentage of the current fill cycle 444 and the completion percentage of total therapy 446 are both numerically and graphically displayed. The user can select a "pause" option 448 to pause therapy.
Figure 60 shows a menu screen with various comfort settings. The menu includes 450 brightness arrows, 452 volume arrows, and 454 temperature arrows. When you select the up arrow or
349 descending in each respective pair, a user can increase or decrease the brightness of the screen, audio volume and fluid temperature. The current brightness percentage, volume percentage and temperature are also displayed. When the values are as desired, a user can select the "accept" button 456.
Figure 61 shows a help menu, which can be accessed, for example, by pressing a help or information button on a previous screen. The help menu may include text 458 and / or an illustration 460 to assist the user. Text and / or illustration can be “context sensitive” or based on the context of the previous screen. If the information provided to the user cannot be conveniently provided on one screen, for example, in the case of a multi-step process, arrows 462 may be provided to allow the user to navigate back and forth between a series of screens. When the user has obtained the desired information, she can select the "backspace" button 464. If additional help is required, a user can select the “call service center” option 466 to have the system contact the call service center.
Figure 62 illustrates a screen that allows the user to set a set of parameters. For example, the display displays the current therapy mode 468 and minimizes the drain volume 470, and allows a user to select these parameters to be changed. The parameters can be changed in many ways such as at
350 select a desired option from an authorized single address style menu. Alternatively, when the user selects a parameter to be changed, a new screen appears, like the one shown in Figure 63. The screen in Figure 63 shows a user adjusting the minimum drain volume by entering a numeric value 472 using a key. 474. Once entered, the user can confirm or cancel the value using buttons 476 and 478. Referring back to Figure 62, a user can then use the "back" and "next" arrows 480, 482 to navigate through a series of parameter screens, each including a different set of parameters.
Once all the desired parameters have been set or changed (for example, when the user has navigated through the series of parameter screens), a screen like the one shown in Figure 64 can be presented to allow a user to review and confirm the values. Parameters that have changed can optionally be highlighted in some way to get the user's attention. When the values are as desired, a user can select the "confirm" button 486.
Automated control of peritoneal dialysis therapy
Continuous ambulatory peritoneal dialysis (CAPD) is traditionally performed manually, with a patient or user transferring dialysis solution from a bag into their peritoneal cavity,
351 having the fluid fixed in the abdomen for three to six hours, and then allowing the fluid to drain into a collection or drainage bag. This is typically done three to four times a day. Automated peritoneal dialysis (APD) differs from CAPD in that APD is accomplished with the help of a peritoneal dialysis machine (cycler) that performs a series of fill-fixation-drain cycles over a period of several hours (for example , when sleeping or at night). In APD, the fluid introduced during a fill phase of the cycle, plus any ultrafiltration fluid, may not drain completely during the next drain phase of the cycle. This may be the result of the user's position in the bed, leading to the sequestration of fluid, for example, in a depression of the peritoneal cavity, and preventing an internal fixation catheter from accessing all the fluid present. In continuous cycle peritoneal dialysis (CCPD), the cycler attempts to perform a complete drain after a fill and fix phase to prevent accumulation of retained fluid (a residual intraperitoneal volume) with each subsequent cycle. The APD generally comprises a plurality of short nightly dialysate exchanges while the user is connected to the cycler and sleeps. At the end of night therapy, a volume of dialysis fluid - possibly of a different composition - can remain in the peritoneal cavity during the day for continuous solute exchange, transfer of waste compounds, and ultrafiltration. In intermittent peritoneal dialysis (IPD), multiple exchanges of dialysate are performed over a period of time (for
352 example, at night), without having a prolonged (or day) residual fixation cycle.
Cycler therapy usually begins with an initial phase of drainage to try to ensure that the peritoneal cavity is empty of fluid. The characteristics of the dialysate solution usually cause some fluid transfer from the patient's tissues to ultrafiltration of the intraperitoneal space. As therapy proceeds through a series of cycles, fluid can accumulate in the intraperitoneal cavity if the drainage phase does not produce the volume of fluid infused during the filling phase, plus the volume of ultrafiltered fluid produced over time. that the dialysate solution is in the peritoneal cavity. In some modes, the cycler can be programmed to issue an alarm to the user when the drain volume has not matched the volume of fluid infused plus the expected ultrafiltration (UF) volume. (The expected UF volume is a function of - among other things - the patient's individual physiology, the chemical composition of the dialysate solution, and the time during which the dialysate solution is expected to be present in the peritoneal cavity.)
In other modes, the cycler may proceed to the next fill-fix-drain cycle if a predetermined amount of drain time has passed and a minimum percentage re-determined (eg 85%) of the preceding fill volume has been drained. In this case, the cycler may be programmed to alarm if the drain flow decreases below a pre-determined rate after a minimum time
353 drain and before the minimum drain percentage has been reached. The cycler may be programmed to alert the user after several minutes (eg two minutes) of unsuccessful attempts to maintain a predetermined flow rate when fluid is being pumped from the peritoneal cavity. A low flow condition can be detectable by the cycler because the increased amount of time required to fill a pump chamber before the stroke end is detected by the controller. A zero flow or non-flow condition may be detectable by the cycler due to detection by the controller of a premature end-of-stroke state. The length of the time delay before alerting the user or initiating a new fill-drain cycle may be programmed to be a few minutes in a low flow condition (for example, 2 minutes), and may be shorter (for example, 30 seconds) in a non-flow condition. A shorter wait time during a non-flow condition may be preferable, for example, because it may be associated with a greater degree of patient discomfort, or it may be the result of a quickly fixable problem, such as a fold in the line or patient's catheter. This time delay can be programmed at the cycler manufacturing stage or can be selected by the clinic professional as a prescription parameter. The extent of the delay may be governed, among other things, by the compensatory desire of the clinic user or professional to stay within the total target therapy time (bearing in mind that it is likely
354 a little dialysis occurs when the intraperitoneal volume (IPV) is low or close to zero). If complete drainage is not achieved, the cycler can also track the estimated amount of fluid to accumulate with each cycle, and issue a warning or alarm if the cumulative IPV exceeds a predetermined amount. This maximum IPV can be a parameter of the prescription of therapy programmed into the cycler by the clinic professional, taking into account the particular physiological characteristics of the patient / individual user.
One method of coping with cumulative fluid retention during a series of CCPD cycles is to convert CCPD therapy to Tidal Peritoneal Dialysis (TPD) therapy. PDT generally comprises a fill-fix-drain cycle in which a volume of drain is intentionally made a prescribed fraction of the initial fill volume (which may also be initially entered by the clinic professional as a prescription parameter) . A predetermined percentage of the infused fluid, or a predetermined amount of fluid, is arranged to remain in the peritoneal cavity during subsequent fill-fixation-drain cycles during therapy. Preferably, subsequent fill volumes are also reduced to match the drain volume (minus expected UF) to maintain a relatively constant residual intraperitoneal volume. For example, an initial fill volume of 3000 ml can be entered at the start of therapy, followed by subsequent drain and [fill plus UF
355 expected] volumes that reach only 1500 ml, that is, 50% of the initial fill volume. The residual fluid reserve in the peritoneal cavity is then completely drained at the end of therapy. In an alternative mode, a complete drain may be attempted after a predetermined or prescribed number of fill-fixation-drain cycles (for example, a complete drain may be attempted after three cycles of tidal therapy, this grouping comprises a cluster of therapy). TPD can be beneficial in that users may experience less discomfort associated with repeated large filling volumes or repeated attempts to completely empty the peritoneal cavity. Low flow conditions associated with small volumes of intraperitoneal fluid can also be reduced, thus helping to avoid extending the total therapy time. To reduce the discomfort associated with trying to drain small residual volumes, for example, the tidal drain volume can be set to 75% of the initial fill volume (plus or minus the expected volume of UF), for example, leaving approximately 25% as reserve or residual volume in the peritoneal cavity for the duration of therapy, or for the duration of a cluster of cycles.
A cycler can also be programmed to convert a CCPD mode of therapy to a TPD mode of therapy during the course of therapy if the user elects to maintain a residual volume of fluid in the peritoneal cavity at the end of subsequent drainage phases (for example , for comfort reasons). In this case, the cycler is programmed to
356 calculate a choice of residual volumes (or volumes as a percentage of initial fill volume) based on the number of extra cycles to be added to therapy and the remaining volume of dialysate to be infused. For example, the cycler controller can calculate the remaining fill volumes based on the remaining cycles that include one, two, or more additional cycles. Having determined the fill volumes for each of these possibilities, the cycler controller can calculate how much residual volume can be left at the end of each remaining drain phase while ensuring that the IPV remains below a prescribed maximum IPV (Max IPV ). The cycler can then present the user with a range of possible residual volumes (as a percentage of the initial fill volume or in volumetric terms) available for each remaining cycle in therapy extended by one, two, or more cycles. The user can make the selection based on the number of extra cycles chosen and the desired amount of post-drain residual volume. Switching to tidal therapy can help reduce the number of low drain flow alerts to the user, which can be particularly advantageous during night therapy.
When switching to tidal mode, the cycler can be programmed to select a reserve or percent residual volume (volume remaining in the peritoneal cavity as a percentage of fill volume plus expected UF). Alternatively, the reserve volume can be selected by the user or by the clinic professional from a
357 value range, optionally with the clinic professional having the ability to select a wider range of possible values than the user. In one modality, the cycler can calculate the effects by adding one, two, or three additional cycles on the remaining fill volumes and the expected percentage of residual IP volume, and give the user or clinic professional the option to select from those values calculated. Optionally, the cycler may be constrained to keep the percentage of residual IP volume below a predetermined maximum value (for example, a percentage of initial fill volume plus expected UF, or a percentage of maximum allowable IPV).
If CCPD is converted to TPD, one or more cycles of therapy (fill-fixation-drain cycles) may need to be added to therapy to use the full prescribed volume of dialysate for the therapy session. The remaining volume to be infused going forward would then be divided by the number of cycles remaining. In addition, the cycler can be programmed to allow the clinician or user to select between extending the total therapy target time to accommodate additional cells (cycle-based therapy), or attempting to maintain therapy target time by adjusting the times. fixation (i.e. shortening) if necessary to reduce fill-fixation-drain cycle times for the future (time-based therapy).
In an alternative mode, the cycler may allow the residual IP volume to fluctuate (optionally within pre-limits
358 determined) from one cycle to the next, depending on how much fluid can be drained within a specified drain time interval. The time available for the drain phase may be limited if the cycler has been programmed to complete therapy within the previously scheduled time, or the drain phase may be terminated to prevent the cycler from attempting to pull fluid at a slow speed for a period long time. When switching from CCPD to TPD, if the cycler adds one or more additional cycles to perform a full therapy with the available dialysate solution, then meeting the scheduled therapy completion time may require shortening fix times, or reducing each drain phase, which could cause the residual volume for the tidal mode to vary, depending on the drain flow conditions. As the cycler estimates and tracks the amount of residual volume, it may be programmed to calculate whether the subsequent fill volume plus the expected UF volume will reach or exceed a prescribed maximum IPV. If so, the cycler can alert and provide the user with two or more options: the user can terminate the treatment, repeat or extend a drainage phase in an attempt to decrease the residual intraperitoneal volume, or add a cycle to reduce the volumes of subsequent filling. After calculating the effect on treatment time of adding one or more additional cycles (increased number of cycles vs. reduced fill and drain times at lower volumes) the cycler can optionally reduce subsequent set times by
359 means a required amount of time generated by one or more additional cycles.
The cycler can be programmed to deliver an optional final fill phase that delivers fresh dialysate of the same or of a different composition to the user's peritoneal cavity for an extended fixation time while not connected to the cycler (for example, a prolonged fixation for one day of therapy, that is, during the day following night therapy). At the user's choice, the final fill volume can be selected to be less than the fill volumes used during night therapy. The cycler optionally can also suggest the user select an optional extra final drain to give the user the opportunity to completely empty the peritoneal cavity prior to infusion of a final fill volume (which can be carried by the user for a relatively long period of time. after the end of night therapy). If this feature is disabled, the cycler may suggest that the user sit or stand up, or otherwise move to mobilize any fluid trapped in the peritoneal cavity during this last phase of drainage.
The cycler can also be programmed to account for an expected amount of ultrafiltration fluid (UF) produced during a fixation phase on or off the machine, and alert the user if a minimum drain volume that includes the infused volume plus this Expected UF is not drained either initially at the start of therapy or during a cycle of
360 filling-fixing-draining during therapy. In one mode, the cycler can be programmed for a minimum initial drain volume and a minimum initial drain time, and pause or end the drain phase if the measured drain flow rate has decreased below a threshold value predetermined by a re-determined number of minutes. The minimum initial drain volume may comprise the volume of the last fill phase in the preceding night therapy, plus an expected volume of UF from the fixation phase of day therapy. If the minimum initial drain volume (or more) is achieved, the minimum initial drain time is reached, and / or the drain flow rate has decreased, the IPV tracked by the cycler controller can be zeroed at the end of the initial draining phase. If not, the cycler can alert the user. The cycler can allow the user to pass the minimum initial drain volume requirement. For example, the user may have manually drained at some point before starting the APD. If the user elects to forgo adherence at the minimum initial drain volume, the cycler can be programmed to perform a complete drain at the end of the first cycle regardless of the type of therapy selected by the user. If enabled, this feature helps ensure that the second fill-fix-drain cycle begins at an IPV that is as close to zero as possible, helping to ensure that a prescribed maximum IPV should not be exceeded during subsequent cycles of therapy.
The cycler may also be programmed to allow the
361 user paused therapy. During a pause, the user may have the option to alter therapy by reducing fill volume, reducing therapy time, ending a planned therapy day, or ending all therapy. Additionally, the user may have the option of immediate draining at any time during therapy. The volume of an unscheduled drain is user selectable, after which the cycler can resume the cycle at the stage where it was interrupted.
The cycler may be programmed to have a prescription or clinic professional mode. A software application can be enabled to allow the clinic professional to create or modify a set of parameters that form the therapy prescription for a particular patient or user, as well as adjust the limits within which a user can adjust the parameters accessible to the user. The clinic professional mode can also allow the clinic professional to set one or more treatment parameters that would otherwise be accessible to a user, as well as lock a parameter to prevent the user from changing it. A clinic professional mode can be password protected to prevent unauthorized access. The clinic professional mode application can be built to interface with a database to read and write the parameters that comprise a prescription. Preferably, a user mode allows the user to access and adjust user accessible parameters during the pre-therapy initiation phase of a therapy. Additionally, a therapy mode
362 Optionally active may be available to a user during therapy, but with access only to a subset of the parameters or parameter ranges available in the user mode. In one mode, the cycler controller may be programmed to allow parameter changes during active therapy mode to affect only current therapy, parameter settings are reset to previously prescribed values prior to subsequent therapies. Preferably, certain parameters cannot be adjusted by the user in any way, adjustable by the user with the concurrence of a clinic professional through a prescription scenario, or adjustable by the user only within a range of values established by a professional. from the clinic when scheduling a prescription. Examples of parameters that may not be adjustable by the user only include, for example, the minimum initial drain volume or time, the maximum initial fill volume, and the maximum IPV. User-adjustable parameters can include, for example, the frequency of tidal drainage in a cluster (for example, adjustable between 1 and 5 cycles), and the percentage of a tidal therapy fill volume to be drained (for example , adjustable above or below a predetermined amount of a default value of, for example 85%). In an alternative modality, the Clinician Professional mode can allow the Clinician to prevent the user from programming a maximum CPI that is greater than a predetermined multiple (eg 200%) of the initial fill volume assigned to a night-fill-fix-drain cycle.
363
The cycler may also be programmed to routinely alert the user and to request confirmation when a user adjustable parameter is entered that is outside of the predetermined ranges. For example, if the maximum IPV has been made user adjustable in the Clinician Professional mode, the cycler may alert the user if they attempt to select a maximum IPV value outside of a fractional range (for example, 130-160% ) of the programmed fill volume for night therapy.
The cycler may also be programmed to alert the user (and possibly seek confirmation) if the initial drain volume has been made adjustable by the user in the Clinician Professional mode, and the user selects an initial drain volume below a pre-determined percentage of the fill volume from the last therapy (for example, if adjusted to be less than 70% of the final fill volume). In another example, the cycler may be programmed to alert the user (and possibly seek confirmation) if the expected total UF volume has been made adjustable by the user through the Clinician Professional mode, and the user selects a volume of Total UF expected to be below a certain percentage of the total volume processed for night therapy (for example, if the total expected UF volume is adjusted to less than 7% of the total night therapy volume). Generally, the expected UF volume can be empirically determined by a clinic professional based on the user's previous experience with dialysis.
364 peritoneal. In a further embodiment, the cycler may be programmed to adjust the expected UF volume value in accordance with the current UF volume in one or more preceding therapy cycles. This volume can be calculated in a CCPD mode by calculating the difference between a measured volume of full drain and the measured fill volume preceding it. In some cases it can be difficult to determine when a peritoneal cavity is completely drained of fluid, and it may be preferable to take an average value of the difference between a complete drain volume and a preceding fill volume over a number of cycles.
Some of the programmable treatment settings may include:
- the number of daytime exchanges using the cycler;
- the volume of solution to be used for each day exchange;
- the total time for a night therapy;
- the total volume of dialysis solution to be used for night therapy (not including a final fill volume if the daytime fixation phase is used);
- the volume of dialysis solution to be infused per cycle;
- in a tidal therapy, the volume of fluid to drain and fill during each cycle (a percentage of the initial fill volume in a night therapy);
- the estimated volume of ultrafiltration to occur during night therapy;
365
- the volume of solution to be supplied at the end of a therapy and to be left in the peritoneal cavity for an extended period (for example, day fixation);
- the minimum initial drainage volume required to proceed with a therapy;
- the maximum known or estimated intraperitoneal volume to be present that the cycler will allow to reside in the patient's peritoneal cavity (which may be based on the measured volumes introduced into the peritoneal cavity, the measured volume removed from the peritoneal cavity and the estimated volume ultrafiltration produced during therapy).
Some of the more advanced programmable treatment settings for the cycler may include:
- the frequency of complete drains to be conducted during tidal peritoneal dialysis;
- the minimum percentage of the volume delivered to the peritoneum during a day therapy that must be drained before subsequent filling is allowed;
- suggest to the user to perform an extra drainage phase at the end of therapy if a pre-determined percentage of the estimated total UF is not collected;
- a minimum length of time required to perform an initial drain before therapy begins;
- a minimum length of time required to perform
366 subsequent drains, either in day therapy mode or night therapy mode;
- variable settling times, adjusted by the cycler controller to maintain a fixed total therapy time when either fill times or drain times have been changed (thus helping to avoid interruptions in the user schedule);
The cycler can provide the user with alerts or warnings about parameters that have been entered outside of the recommended range of values. For example, a warning can be issued if:
- the minimum initial drain volume before therapy is less than a pre-determined percentage of the currently prescribed final fill volume at the end of previous therapy (eg <70%);
- the maximum IPV is outside a predetermined percentage range of fill volume per cycle (eg <130% or> 160%);
- the UF volume threshold to trigger an alert to perform an extra drain at the end of therapy is less than a predetermined percentage of the estimated UF volume per therapy (eg <60%);
- the calculated or entered fix time is less than a predetermined number of minutes (eg <30 minutes);
- the estimated volume of UF per therapy is greater than a predetermined percentage of the total volume of dialysis solution per therapy (for example,> 25%);
367
- the sum of all solution bag volumes for a therapy should be somewhat greater than the volume of solution used during a CCPD therapy session, to account for fluid line initiation and fluid loss to drain during air mitigation procedures.
In clinic professional mode, in addition to having a selectable maximum IPV, the cycler may be programmed to accept separate minimum drain times for initial drains, day therapy drains, and night therapy drains. In user mode or active therapy mode, the cycler may be programmed to prevent the user from skipping or shortening the initial drain phase at the start of therapy. Additionally, the cycler can allow early termination of the initial drain phase only after a series of low drain flow alerts have been issued. (An initial alert can instruct the user to change or reposition the peritoneal dialysis catheter, which can then follow with additional alternative instructions if low flow conditions persist, up to a maximum number of alerts.) The cycler may also require the user to confirm any changes the user makes to the planned therapy, including omitting a phase. The clinic professional can specify a prescription setting to prevent the user from skipping a drainage phase during night therapy. During therapy, the cycler controller may be programmed not to reset the IPV to zero unless the drain volume exceeds the fill volume
368 preceding (to account for additional IPV produced by ultrafiltration). The cycler can also be programmed to display the estimated IPV to the user during fills, and can notify the user if any drain volume exceeds the fill volume by a predetermined amount (for example, a drain volume greater than the fill volume plus the expected UF volume).
The cycler may also be programmed to identify user input errors and notify the user of apparent input errors. For example, the number of cycles during a therapy calculated by the cycler, based on the prescription parameters entered by the clinician or user, should be within a predetermined range (eg 1-10). Similarly, the fixation time calculated by the cycler should be greater than zero. Additionally, the maximum IPV entered by the user or the clinic professional should be greater than or equal to the filling volume per cycle, plus the expected volume of UF. Additionally, the cycler may be programmed to reject an entered value for the maximum IPV that is greater than a predetermined amount above the fill volume per cycle (for example, maximum IPV <200% of initial fill volume). In some cases, it may be desirable for the cycler to be programmed to set the maximum IPV not greater than the last fill volume if the solution is to remain in the peritoneal cavity for an extended period of time, such as during daytime therapy. In this case, the cycler may be programmed to alert
369 to the user if the cycler controller calculates that the last drain volume represents less than full drain, after which the cycler may provide the user with the choice to terminate therapy or undertake another drain phase.
Managing growing IPV while minimizing alarms
In one embodiment, the cycler may be programmed to track and deliver an increasing IPV during a therapy without converting therapy from continuous cycle peritoneal dialysis (CCPD) therapy to standard tidal peritoneal dialysis (TPD) therapy, which would set residual volume at a percentage of initial fill volume. Rather, an adaptive tidal therapy mode can be initiated, in which the residual volume is allowed to fluctuate or float in response to any slow draining conditions that may be encountered during any phase of drainage. The cycler may be programmed to allow this mode to operate, as long as any subsequent fill volume plus the expected UF does not exceed a prescribed maximum IPV (Max IPV). Thus, the fixation phase IPV may be allowed to increase or decrease during therapy to a maximum IPV, preferably set by a clinic professional in the clinic professional mode. In this adaptive tidal therapy mode, at each drain phase during a therapy, the cycler continues to attempt a complete drain within the available time, or always and
370 when the low flow or non-flow condition has not been detected for a prescribed or preset number of minutes. The residual volume at the end of the drain phase is allowed to vary or float, as long as it does not exceed an amount that would lead to exceeding the maximum IPV in the next fill phase during the next fixation phase. In a preferred embodiment, the cycler may be programmed not to issue an alert or alarm to the user, as long as it calculates that the fill phase or subsequent setting phase will not reach or exceed the maximum IPV.
The cycler may be programmed to deliver full fill volumes during each cycle of a therapy until the cycler controller calculates that the next fill volume will likely cause the IPV to exceed the maximum IPV. At a convenient time (such as at the end of a drain phase), the cycler controller may be programmed to calculate a maximum residual IP volume, which represents the maximum allowable residual IP volume at the end of a drain for allow the next cycle to proceed with the previously programmed fill volume. Partial drains will be allowed by the cycler without alarming or issuing an alert, as long as the amount of fluid drained brings the residual IPV below the maximum residual IPV. If the estimated or predicted IPV at the end of a drain phase is less than the maximum residual IPV, the cycler can proceed with a full fill phase in the next cycle without risking exceeding the Max IPV. If the estimated IPV at the end of a drain is greater than the IPV
371 Maximum residual, the cycler controller can trigger an alert to the user that subsequent fill plus UF may exceed the maximum IPV. In one mode, the cycler can display various options for the user to respond to this alert: they can allow the user to end therapy, attempt another drain phase, or proceed to enter a revised cycle therapy mode, in which each volume Subsequent fill is reduced and one or more cycles are added to the therapy (thus ensuring that the remaining volume of fresh dialysate is used during that therapy). In one modality, a clinician or user can enable the cycler at the beginning of therapy to automatically enter this revised cycle therapy mode without having to alert the user during therapy.
In some circumstances, the number of additional cycles may be limited by the planned total therapy time. For example, the duration of night therapy may be limited by the time the user is scheduled to wake up or get up to go to work. For night therapy, the cycler controller may be programmed, for example, to prioritize the use of the entire dialysate solution that was planned for therapy in favor of ending therapy on schedule. If the clinician or user has selected that the fix time is adjustable, then the cycler controller (1) will add one or more cycles to ensure that the fill volume plus expected UF does not exceed the maximum IPV; (2) will ensure that all dialysis solution is used for therapy; e (3) will try to reach the target therapy end time
372 shortening the fixing times of the remaining cycles. An alternative option available to the user is to extend the end of therapy time. In a preferred embodiment, the cycler is programmed to add one or two additional cycles to therapy to allow for a reduced fill volume to prevent exceeding the maximum IPV. The cycler controller is programmed to recalculate the maximum residual IPV using the reduced fill volume caused by the increased number of cycles. Thus, if a low flow condition during drainage occurs at the same IPV, the new upper maximum residual IPV may allow dialysis to proceed without exceeding the maximum IPV. If the fill volume cannot be reduced enough to add an extra maximum allowable number of cycles (for example, 2 cycles in an exemplary night therapy scenario), then the cycler may present the user with two options: retry a drain phase or end therapy. The cycler may be programmed to reset the fill volume again after a fill volume adjustment, possibly adding an additional cycle, if a low flow condition at the end of the drain is again at an IPV above the residual IPV maximum restarted again recalculated. Thus, the cycler may be programmed to repeatedly adjust subsequent fill volumes to prevent exceeding the maximum IPV if a premature low flow condition is repeatedly encountered.
Limitation of replacement in the reductions of the time of
373 fixation
In one embodiment, if the cycler reduces fill volumes by adding one or more cycles, then it will also reduce the settling time to try to keep the therapy session within the target total therapy time. This mode can be useful for night therapy, so that the patient can be reasonably sure that the therapy will be over before a planned time to wake up in the morning. However, the cycler will continue to replenish the contents of the warmer bag as needed during therapy, replenishment generally occurs during the fixation phases (when the PD cassette is not otherwise pumping to or from the patient). Therefore, in some circumstances, the total therapy time may need to be extended when the required reduction in remaining fixation times leads to a total remaining fixation time that is less than the total estimated time required to replenish the contents of the bag. the heater with the remaining fresh dialysate. The cycler controller can therefore calculate a reduction in the maximum available fix time for the remaining therapy cycles, and extend the total therapy time to ensure that the remaining fresh dialysate is heated appropriately. Because the cycler controller keeps track of the dialysate volume in the heater bag, the dialysate temperature in the heater bag, and the remaining fresh dialysate volume that is programmed to be infused, you can calculate an estimate of the amount of time needed to replenish
374 the contents of the heater bag at a predetermined volume (given its intrinsic pumping capacity), and the time required to bring the dialysate in the heater bag to a prescribed temperature before it is infused into the user. In an alternative embodiment, the cycler controller may interrupt pumping operations to or from the user at any time to engage the pumps to replenish the contents of the heater bag. The cycler controller may be programmed, for example, to prevent the volume of fluid in the heater bag from falling below a predetermined volume at any time during therapy, other than the time during the last cycle.
In one embodiment, the cycler may be programmed to supply fluid to the heater bag at a higher flow rate than when it is transferring fluid to or from the user. If binary valves are used to regulate the flow of control fluid or gas between the positive / negative pressure tanks and the control or drive chambers of the cassette pumps, the controller can issue on-off commands to the valves at different levels of pressure measured in the control chambers or pump drives. Thus, the pressure threshold in the control chamber or pump drive at which the controller activates a shutdown command to the binary valve may have an absolute value that is greater during delivery to or from the heater bag than the threshold corresponding pressure when the cycler is supplying or withdrawing fluid to or from the peritoneal cavity of the
375 user. A higher average pressure applied to the pump diaphragm can be expected to result in a higher flow rate of the liquid being pumped. A similar approach can be used if variable port valves are used to regulate the flow of control fluid or gas between the pressure tanks and the control or drive chambers of the cassette pumps. In this case, the controller can modulate the flow resistance offered by the variable orifice valves to maintain a desired pressure in the pump control chamber within the predetermined limits while the pump diaphragm is moving. through his blow.
Exemplary modes of therapy
Figure 67 is a graphical illustration (not to scale in either volume or time) of an adaptive tide mode of the cycler when in a CCPD mode. Initial drainage at the beginning of therapy is omitted for clarity. The maximum IPV (Max IPV) 700 is a prescription parameter preferably adjusted by the clinic professional. The initial fill volume 702 is preferably also established by the clinic professional as a prescription parameter. The expected volume of UF is represented by increasing the additional IPV 704 during binding phase 706. The expected volume of UF for complete therapy can be entered by a clinician in the prescription, and the cycler then can calculate fixation time per cycle based on number of cycles during therapy, and thus volume
376 expected UF per cycle. It is noted that ultrafiltration is expected to occur throughout the fill-fixation-drain cycle, and the expected volume of UF may include the volume of ultrafiltered fluid throughout the cycle period. In most cases, settling time is much larger than fill or drain times, making ultrafiltration volumes during fill or drain relatively insignificant. (Fill and drain times can be adjustable by altering the pressure set points used by the controller to regulate the control valves between the pressure reservoirs and the pumps. However, adjusting the supply flow rates and pressures of liquid to the user is preferably limited to ensure user comfort). Thus, the expected volume of UF per cycle 704 is expected to be reasonably representative of ultrafiltration during the cycle. The drain phase 708 of the cycle in this example is a complete drain, as would occur in a CCPD therapy mode.
The maximum residual volume 710 can be calculated by the cycler controller once the IPV Max 700, the initial fill volume 702 and the expected volume of UF are entered by the clinic professional. The 710 maximum residual volume is an indication of the 712 headroom available in the peritoneal cavity to accommodate more fluid before reaching IPV Max 700. In an adaptive tidal mode within a CCPD therapy mode, as long as a drain volume 714, 716 leaves an estimated residual volume 718, 720 less than the volume
377 Maximum residual 710, subsequent fill volume 722, 724 may remain unchanged as IPV Max 700 is not expected to be violated. As shown in Figure 67, the occurrence of a low flow condition in residual volumes 718 and 720 activates the cycler to initiate the next fill phase 722 and 724. During this form of therapy, the cycler will continue to attempt to perform a full drain 726 within an expected time assuming that no low flow or no flow condition is found before the estimated IPV of zero is reached. Thus, even if a complete drain is not performed (due to a low flow or no flow condition), in this case, the full fill volumes will continue to be infused, the residual IPV will be allowed to float within a predetermined range, and preferably the user will not be bothered by any alarm or alert notifications.
Figure 68 is a graphical illustration of how the cycler can handle incomplete drains that fail to reach the maximum residual IPV 710. In this case, the drain cycle 730 of the third cycle encounters a low flow or non-flow condition that prevents the cycler to drain the peritoneal cavity below the maximum residual IPV 710. Given the estimated residual volume 732 (the estimated residual volume after a pre-determined duration of a low flow condition), the cycler calculates that a subsequent fill phase volume 734 will likely cause the prescribed IPV Max 700 to be reached or exceed 736. Therefore, at the end of drain phase 730, the cycler can alert the user to this
378 situation. The user may then have the option to end therapy, instruct the cycler to retry a drain phase (possibly after changing positions or repositioning the PD catheter), or instruct the cycler to enter a cycle therapy mode. revised in which subsequent fill volumes are reduced to one or more added cycles to complete therapy with the planned total dialysate volume. To stay within the prescribed or prescribed therapy time, the cycler can calculate the duration of the modified cycles by reducing fill and drain times to account for reduced fill and drain volumes, and then determine if and how much fix times they need to be reduced to meet the designated end time of the therapy session.
Optionally a user can enable a revised CCPD cycle mode at the start of a therapy, so the occurrence of a low flow condition during therapy can activate the revised cycle mode without disturbing the user with an alert or alarm. Otherwise, the user can select the revised cycle mode after the occurrence of a low flow condition above the maximum residual IPV. If the user chooses to enter a revised cycle mode, the cycler controller can calculate the required fill volumes for each of one, two, or more additional cycles (the remaining fill volume divided by the remaining planned cycles plus the one or plus additional cycles). If an additional cycle produces a fill volume (plus expected UF) low enough
379 To avoid reaching or exceeding the IPV Max, the cycler (either automatically or at the user's option) will resume the CCPD to that new fill volume 738. Otherwise, the cycler controller will calculate a new fill volume based on two additional cycles of therapy. (Very rarely, more than two additional cycles may be required to ensure that the IPV Max is not violated during the remaining therapy. If additional cycles require a substantial reduction in remaining hold times, the cycler may alert the user, particularly if a minimum hold time has been prescribed, or the replenishment limitations of the contents of the heater bag will require lengthening of the time. total therapy). The now reduced fill volume 738 allows the cycler controller to recalculate a revised maximum residual IPV 740, which is a function of the sum of the new fill volume plus the expected volume of UF per cycle. Any subsequent drainage phase that leaves an estimated residual IP volume less than the revised maximum residual volume 740 will preferably not trigger any additional alerts or alarms to the user, allowing the adaptive mode of tidal therapy to remain enabled. In one modality, the cycler can recalculate the expected volume of UF if he has reduced the duration of the remaining fixation phases to stay within the planned total therapy time. Any recalculated reduction in the expected volume of UF may further increase the revised maximum residual HPI. In the example shown in Figure 68, the cycler continues to perform
380 CCPD mode, and it turns out to be able to drain completely in the remaining cycles. In order not to further bother the user, the cycler can optionally refrain from making any additional adjustments to therapy (particularly if the total dialysate volume and total therapy time have been kept within prescribed parameters).
Figure 69 illustrates that a planned standard peritoneal tidal dialysis (TPD) therapy may also undergo a revised cycle mode of TPD therapy if the cycler controller calculates that the user's Max IPV is likely to be reached or exceed during therapy. In this example, a user or clinic professional has selected a standard tidal therapy, in which a residual IP volume 742 has been selected (in actual volumetric terms or as a percentage of the initial fill volume). As an optional feature of the cycler, the clinician or user has also chosen to perform a full drain 744 after every three tidal drain fill-fix cycles, comprising a cycle cluster during a therapy session. In this example, a low flow condition that prevents drainage below the maximum residual volume 710 occurs at the end of the third cycle 746. At the option of the user or clinic professional, the cycler alerts the user to either choose to end therapy, repeat a drain phase, or initiate a revised cycle TPD therapy, or the cycler is automatically allowed to initiate a TPD therapy revised cycle. In this case, the addition of a sixth cycle with a consequent reduction in the volume of
381 Fill to a revised fill volume of 748 is sufficient to avoid exceeding the IPV Max 700, which would otherwise have occurred at 750. In this example, the cycler proceeds to perform a full drain 744 at the end of a cluster, but resumes after that's a standard TPD therapy. If the planned residual volume has been specified to be a percentage of the initial fill volume of the cluster, then the percentage can be applied to a revised residual IPV 752. The cycler can then calculate the subsequent drain volumes 754 by calculating the appropriate fraction of the revised fill volume 748 plus the expected volume of UF to drain the revised residual IPV 752. Any subsequent fill volume 758 may remain similar to the revised fill volume 748 , as long as the cycler calculates that the IPV Max 700 will not be violated. Alternatively, subsequent fill volumes can be reduced in a way designed to keep a revised fixation phase IPV relatively constant 756. In this case, the cycler controller may be programmed to do the additional calculations necessary to ensure that the complete remaining dialysate solution will be appropriately divided between a revised 748 fill volume and reduced subsequent fill volumes to maintain a fixation phase IPV revised 756. In an alternative modality, the practitioner or user can select the prescribed residual IP volume 742 to be relatively volumetrically fixed throughout therapy. In this case, the cycler controller can convert the percentage value of the volume of
382
Residual IP 742 at a volumetric value (eg, in milliliters), and continue to use that target residual volume after the revised cycle mode has been instituted. In either case, the cycler controller can continue to apply the IPV Max 700 limitation when calculating any revised fill volume.
Figure 70 illustrates how an adaptive tidal therapy mode can be employed during standard tidal therapy. In this example, a slow drain condition 760 is below the maximum residual volume 710. As an optional feature of the cycler, the user or clinic professional has also chosen in this example to perform a full drain 764 after every four fill-tide-drain cycles, comprising a cycle cluster during a therapy session. In this case, the cycler calculates that the IPV Max 700 will not be reached if the tidal fill volume 762 is maintained. The cycler may be programmed to continue tidal therapy at a revised residual IP volume of 760 to avoid another slow drain condition. (Alternatively, the cycler may be programmed to attempt to drain back to the previously prescribed 742 residual IP volume.) Because tidal therapy can continue without risk of violating IPV Max 700, the user need not be alerted to the institution of a revised or floating residual volume of adaptive tidal therapy mode. A complete 764 drain starts as prescribed, and if successful, the cycler controller can re-institute the originally prescribed therapy parameters.
383
In one modality, the cycler may be programmed to alert the user if complete drainage cannot be achieved at the end of a tidal therapy cluster.
Although aspects of the invention have been described in conjunction with specific embodiments thereof, it is apparent that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the embodiments of the invention as set forth herein are intended to be illustrative and not limiting. Various changes can be made without departing from the spirit and scope of the invention.
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Contents10
33 sheets
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360 members in 10 offices
Priority claims3
| Document | Office | Kind | Date |
|---|---|---|---|
| 61555926 | United States of America | – | |
| 201161555926 | United States of America | P | |
| 2012063336 | United States of America | W |
Members360
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| CA2712930A1 | Canada | A1 | |
| CA2712945A1 | Canada | A1 | |
| CA2712947A1 | Canada | A1 | |
| CA2712950A1 | Canada | A1 | |
| CA2712953A1 | Canada | A1 | |
| CA2713028A1 | Canada | A1 | |
| CA2965013A1 | Canada | A1 | |
| CA2965346A1 | Canada | A1 | |
| CA3017406A1 | Canada | A1 | |
| CA3090309A1 | Canada | A1 | |
| CA3103415A1 | Canada | A1 | |
| CA3170800A1 | Canada | A1 | |
| CA3171180A1 | Canada | A1 | |
| CA3171851A1 | Canada | A1 | |
| CA3187333A1 | Canada | A1 | |
| WO2009094179A2 | World Intellectual Property Organization (WIPO) | A2 | |
| WO2009094182A2 | World Intellectual Property Organization (WIPO) | A2 | |
| WO2009094183A1 | World Intellectual Property Organization (WIPO) | A1 | |
| WO2009094184A1 | World Intellectual Property Organization (WIPO) | A1 | |
| WO2009094185A2 | World Intellectual Property Organization (WIPO) | A2 | |
| WO2009094186A2 | World Intellectual Property Organization (WIPO) | A2 | |
| WO2009094179A3 | World Intellectual Property Organization (WIPO) | A3 | |
| WO2009094182A3 | World Intellectual Property Organization (WIPO) | A3 | |
| WO2009094185A3 | World Intellectual Property Organization (WIPO) | A3 | |
| WO2009094186A3 | World Intellectual Property Organization (WIPO) | A3 | |
| MX2010008011A | Mexico | A | |
| MX2010008015A | Mexico | A | |
| MX2010008012A | Mexico | A | |
| MX2010008014A | Mexico | A | |
| MX2010008013A | Mexico | A | |
| MX2010008016A | Mexico | A | |
| KR20100117617A | Republic of Korea | A | |
| EP2252345A1 | European Patent Office (EPO) | A1 | |
| EP2252346A2 | European Patent Office (EPO) | A2 | |
| EP2252347A1 | European Patent Office (EPO) | A1 | |
| EP2254615A2 | European Patent Office (EPO) | A2 | |
| EP2254616A2 | European Patent Office (EPO) | A2 | |
| EP2254617A2 | European Patent Office (EPO) | A2 | |
| CN101977642A | China | A | |
| US2011071465A1 | United States of America | A1 | |
| JP2011509799A | Japan | A | |
| JP2011509801A | Japan | A | |
| JP2011509802A | Japan | A | |
| JP2011509803A | Japan | A | |
| JP2011509804A | Japan | A | |
| US2011092893A1 | United States of America | A1 | |
| US2011092894A1 | United States of America | A1 | |
| JP2011512882A | Japan | A | |
| US2011098635A1 | United States of America | A1 | |
| US2011106002A1 | United States of America | A1 | |
| US2011125085A1 | United States of America | A1 | |
| EP2335753A1 | European Patent Office (EPO) | A1 | |
| CA2804216A1 | Canada | A1 | |
| CA3024418A1 | Canada | A1 | |
| CA3210090A1 | Canada | A1 | |
| CA3210106A1 | Canada | A1 | |
| WO2012006425A2 | World Intellectual Property Organization (WIPO) | A2 | |
| WO2012006425A3 | World Intellectual Property Organization (WIPO) | A3 | |
| US2012123322A1 | United States of America | A1 | |
| US8197439B2 | United States of America | B2 | |
| WO2012006425A8 | World Intellectual Property Organization (WIPO) | A8 | |
| SG186939A1 | Singapore | A1 | |
| MX2013000212A | Mexico | A | |
| WO2013067359A2 | World Intellectual Property Organization (WIPO) | A2 | |
| EP2591385A2 | European Patent Office (EPO) | A2 | |
| AU2012327182A1 | Australia | A1 | |
| US2013165847A1 | United States of America | A1 | |
| US2013184638A1 | United States of America | A1 | |
| JP2013533793A | Japan | A | |
| WO2013067359A3 | World Intellectual Property Organization (WIPO) | A3 | |
| JP2013240647A | Japan | A | |
| JP5416137B2 | Japan | B2 | |
| JP5416138B2 | Japan | B2 | |
| JP5425810B2 | Japan | B2 | |
| US8708950B2 | United States of America | B2 | |
| JP2014100581A | Japan | A | |
| JP2014111114A | Japan | A | |
| JP2014111115A | Japan | A | |
| EP2773395A2 | European Patent Office (EPO) | A2 | |
| US8840581B2 | United States of America | B2 | |
| JP5595930B2 | Japan | B2 | |
| SG11201402017QA | Singapore | A | |
| JP5603255B2 | Japan | B2 | |
| US2014323954A1 | United States of America | A1 | |
| JP2014223550A | Japan | A | |
| JP2014533155A | Japan | A | |
| US2014364800A1 | United States of America | A1 | |
| JP2015016343A | Japan | A | |
| JP2015016380A | Japan | A | |
| MX2014005451AThis record | Mexico | A | |
| US2015057603A1 | United States of America | A1 | |
| SG10201408587VA | Singapore | A | |
| EP2254617B1 | European Patent Office (EPO) | B1 | |
| US9022969B2 | United States of America | B2 | |
| US9028440B2 | United States of America | B2 | |
| CN101977642B | China | B | |
| KR20150068487A | Republic of Korea | A | |
| US9078971B2 | United States of America | B2 | |
| JP5749768B2 | Japan | B2 | |
| CN104800903A | China | A |
1 legal event, as the office reported them to INPADOC
Events
| Event | Code | |
|---|---|---|
| Grant or registrationFG | FG |
Numbers
- Publication
- 2014005451
- Application
- 5451
Titles2
- Spanish
- SISTEMA DE TRATAMIENTO MEDICO Y METODOS QUE USAN UNA PLURALIDAD DE LINEAS DE FLUIDO.
- English
- MEDICAL TREATMENT SYSTEM AND METHODS USING A PLURALITY OF FLUID LINES.
Classification
- CPC, 35
- A61M1/28
- A61M2205/122
- A61M2205/128
- A61M2205/15
- A61M2205/3368
- A61M2205/50
- A61M2205/8212
- A61M1/1664
- A61M1/282
- H05B1/025
- A61M2205/36
- A61M1/288
- A61M2205/8206
- Y10T137/85978
- Y10T137/6416
- F04B43/02
- A61M1/153
- A61M1/155
- A61M1/1565
- A61M1/159
- A61M1/1522
- A61M1/1561
- Y02E60/10
- A61M1/281
- A61M1/284
- A61M2205/18
- A61M2205/3331
- A61M2205/3334
- A61M2205/3379
- A61M2205/3327
- A61M60/113
- A61M2205/33
- A61M2210/1017
- F16L53/00
- F17D1/00
- IPC, 2
- A61M1 28
- F16L53 00