Blood treatment device with balanced flow

The invention relates to a balancing Disposable for Bilan Grace of liquids for medical treatment apparatus as well as a medical treatment device with a system tray for receiving such a balancing disposables.

For the removal of urinary metabolites and the liquid withdrawal various methods for machine-blood purification or blood treatment are used in chronic renal failure. In hemodialysis (HD) of the diffusive substance transport, hemofiltration (HF) predominates is a convective substance transport through the membrane before. A combination of both methods is the hemodiafiltration (HDF). In peritoneal dialysis (PD), no extracorporeal circulation is needed and utilized the peritoneum as a contact membrane.

Because of the large exchange volumes consists of said process, as well as in the continuous arteriovenous HF, continuous veno-venous HF and the plasma filtration (PF) the need for accurate accounting of confiscated liquid on the one hand to the liquid supplied on the other hand and to ultrafiltered quantity over the entire treatment period. The prior art includes gravimetric and volumetric balancing systems.

DE 41 16 178 C1 describes a device for purifying blood with volumetric fluid balancing for HF, HDF and PF systems. The known blood treatment device has a balancing chamber, which is divided by a flexible wall in a first and a second balancing chamber half, wherein the first chamber half is connected to a filtrate conduit and the second chamber half with a substituate. From the first chamber half a filtrate outlet goes off to an outlet, while from the second chamber half a Substituatauslaßleitung going, which is connected to the bloodstream. Filtrate and substituate the balancing chamber are alternately supplied to each of a connected in the filtrate or substituate equalizing chamber by means of a printing device. The compensation chambers are filled with the known filtration device with the filtrate or substituate and emptied after opening of blocking clamps by means of the printing device in one of the balancing chamber halves, simultaneously emptied the other balancing chamber half under pressure in the respective outlet conduit. The balancing chamber and the balancing chambers form a multi-part set that is discarded after a single use. The compensation chambers of the sets are designed as flexible connected to the filtrate or Substituatleitungen plastic bag, while the housing of the balancing chamber is a rigid plastic body. Since the disposable of the known filtration device consists of several individual components, handling more difficult. Furthermore, the production of multipart disposables is relatively expensive.

The DE 34 28 828 C2 describes a device for transporting blood in an extracorporeal circuit with a pump chamber, the pump chamber having a duration membrane enclosing a cavity. In the cavity there is an exchange membrane which consists of elastic material and the shape of a tube has, connected at one of its ends with a connecting piece for two lines. The pump chamber of the pumping chamber is connected via a line with a mechanical piston pump in conjunction, to fill the pump chamber with a working fluid can, so that the tubular exchange membrane is compressed.

The invention has for its object to provide a balancing Disposable for Bilan Grace of liquids for medical treatment apparatus, which is easy to handle and inexpensively manufactured. Furthermore, the invention has for its object to provide a medical treatment device with a system tray for receiving such a balancing disposables.

The problem is solved according to the invention with the features of claim 1 and 8 respectively.

The balancing Disposable invention is designed as a foil pouch, and has both a balancing chamber and two standing with the respective chamber halves of the balancing chamber in fluid communication compensating chambers. The balancing Disposable consists essentially of two films that are associated with the formation of the divided by a flexible wall in the two chamber halves balancing chamber and the two compensation chambers and the line connecting the individual chambers channels each pressure-tight.

In the balancing Disposable invention, the operating principle of the volumetric accounting can be maintained with the reciprocal filling and pressing of the two balancing chamber halves. The fixed volume setting of the balancing chamber halves is achieved by a corresponding system insert the balancing device, in the disposable of the invention can be inserted appropriately. The system tray has two rigid receiving body with trough-shaped recesses on the over- or under-grip the balancing chamber of disposables. When filling one of the two chamber halves, the outer sheets of disposables create to the inner surfaces of the two shell halves, so that a certain balancing volume is predetermined. In the system of insertion and the known compression devices are integrated, which act on the connected in the first and second inlet channel compensation chambers with pressure. Furthermore, the reciprocal clamping of the respective channels with clamping devices, which are also incorporated in the system insert occurs.

Using the balancing disposables in the PD, the principle shall apply. Here, however, substituate is not continuously recognized at filtrate, but first promoted fresh dialysate on both balancing chamber halves by additional terminals and connections and the spent dialysate encouraged to linger in the abdomen in the same manner in the drain, ie there is no direct displacement of substituate through the filtrate and vice versa. The mass balance is via adding the individual amounts off per chamber filling or be fed.

The Disposable invention can be economically produced in a simple manner in a single welding or bonding process. Since the disposable includes all components of the balancing device, its handling is greatly simplified. The one-piece disposable can be inserted with a handle in the corresponding system insert the medical treatment apparatus or replaced after use with a new plastic bag. Proves to be advantageous, the very flat design, which makes it possible to offer the flexible film bag as a sterile unit in a flat plastic bag, which is insensitive to shock and can be easily stacked and transported.

The films of balancing disposables can in principle welded or glued. Preferably, the films are welded to each other but in order to achieve a pressure-tight connection.

The flexible wall separating the first chamber half of the balancing chamber of the second chamber half is formed by an intermediate film which connected inserted between the first and second film in the area of ​​the balancing volume and pressure-sealed to the outer films to form the first and second chamber half, for example, welded or glued. By suitably welding in the inputs and the outlets and by applying the films at overpressure two balancing chamber halves are created that are completely separated by the intermediate film. For filling of a chamber, the same amount of liquid is automatically pressed out into the other chamber.

Since form during welding of the films at the edges of the weld material residue, a relatively large contact pressure is required to disconnect the inlet and outlet pressure-tight. Advantageously, the channels between the upper and lower films of the disposables are therefore inserted flexible plastic tubes and welded to the outer sheets or glued at least in the area of ​​clamping points. The seamless on its inner side channels can disconnect easily with relatively little pressure. The flexible plastic tubes also reduce the risk that the welded film channels collapse even at low vacuum and stop the reflux. The clamping off of the channels advantageously takes place by ram, which are provided in the body of a receiving system insert and cooperate with clamping edges, which are arranged on the opposite side in the other receiving body.

The balancing Disposable is preferably provided with openings for receiving fixing pins that can be integrated in the system tray. In this way, an exact positioning of the disposable between the receiving bodies of the system insert is ensured. Within the system insert the disposable is preferably held at its edges. In the receiving bodies of the system insert clamping edges are therefore advantageously provided, which take the Disposable from both sides.

In an advantageous embodiment, a serpentine channel in the Disposable is formed, which opens into the second equalization chamber. The serpentine channel makes it possible to control the temperature of the led in the second equalization chamber liquid through the slides through by heating plates, which are placed externally on the disposable. The heating plates may be part of the receiving body of the system insert, wherein the flow guide and turbulence within the film can be ensured by an appropriate structure in the inset.

In a further preferred embodiment, the balancing Disposable has a buffer chamber which is switched to the second outlet channel. This buffer chamber makes it possible to convert the occurring only a balancing volume when using pulsatile flow in a quasi-continuous flow. The buffer effect is achieved here through an opening provided in the system tray and with the balancing Disposable cooperating mechanical coupling, which empties the buffer chamber when filling the first equalization chamber. Thereby, the blood side pressure monitoring is simplified and reduces the pulsation of the needle.

The balancing chamber, which preferably has an oval shape due to better utilization and width of the rectangular equalizing chambers are preferably arranged such that the longitudinal axis of the balancing chamber is transverse to the longitudinal axes of the compensation chambers. This space-saving arrangement of the chambers is possible.

two embodiments of balancing Disposables invention and an embodiment of the system insert a blood treatment apparatus for receiving the disposables are explained below with reference to the drawings.

Show it:<dl id="dl0001"><dt>Fig. 1</dt><dd>the balancing Disposable invention in plan view,</dd><dt>FIG. 2</dt><dd>a section through the balancing chamber of balancing Disposables,</dd><dt>Fig. 3a</dt><dd>a section through the range between the two receiving bodies of the system insert balancing chamber of balancing disposables, the lower chamber half filled and the upper half of the chamber is emptied</dd><dt>FIG. 3b</dt><dd>a section through the range between the two receiving bodies of the system insert balancing chamber of balancing disposables, the lower chamber half emptied and the upper chamber half is filled</dd><dt>Fig. 4</dt><dd>a second embodiment of an integrated heating film Bildanzierdisposables with, and </dd><dt>Fig. 5</dt><dd>the unfolded system insert the medical treatment device with the two receiving bodies for receiving the balancing Disposables invention.</dd></dl>

FIG. 1 shows the balancing Disposable for medical treatment device. The balancing Disposable has two flexible, substantially rectangular plastic films 1, 2, which are provided along with the reference numeral 3 seams are welded to each other such that a total of four chambers 1,2 are formed between the upper and lower foil. In the center of disposables is a balancing chamber 4 with an oval shape. On one side of the balancing chamber, a first rectangular equalizing chamber 5 and a second rectangular equalizing chamber 6 are arranged, have the same storage volume. On the other side of the balancing chamber 4 a buffer chamber 7 is arranged.

The balancing chamber 4 comprises a flexible and elastic wall 8 which divides the chamber into a first lower and a second upper chamber half 9, 10, each chamber half 9, 10 to an input 11, 12 and an output 13, 14 is provided. The flexible wall 8 is made of a in FIG. 1, indicated by dashed lines rectangular intermediate sheet, which is inserted in the area of ​​the balancing volume between the upper and lower foil 1, 2, and with the formation of the two chamber halves 9, 10 with the outer sheets 1, 2 , is welded (Fig. 2).

The lower half of the chamber 9 is connected via a first inlet channel 17 with the first balance chamber 5 in fluid communication, while the upper balancing chamber half is connected via a second inlet channel 15 with the second equalization chamber 6 and a diagonally opposite second outlet channel 16 with the buffer chamber 7 in fluid communication. The output 14 of the first balancing chamber half 9 a first outlet channel 18 is connected. The inlet and outlet channels 15 and 18 between the chambers 4 to 7 are formed by flexible plastic tubes 19, which are inserted between the upper and lower foil 1, 2 and are welded to the outer sheets. The inputs and the outputs of the tubes 19 are welded to the intermediate film 8 of the balancing chamber 4 that an input and an output above and is an input and an output below the intermediate film 8 and a direct connection between the upper and lower balancing chamber half 9, 10 is not given.

The inserted plastic tubes 19 not only prevent collapse of the tube channels at reduced pressure, but also create represented by circles in Fig. 1 nips 20, which can be pressure-tight disconnect. With the receipt of the first equalization chamber 5 is a first lead 21 to the input of the second equalization chamber 6 is a second supply line 22, with the end of the first exhaust passage 18, a first outlet conduit 24 and to the output of the buffer chamber 7 is a second outlet line 23 welded. The input and outlet lines 21 to 24 may be provided with not shown in FIG. 1 connectors. Furthermore, the balancing Disposable has laterally arranged next to the balancing chamber openings 43 for receiving fixation pins. The chambers are each to be regarded as a bag assemblies.

The balancing Disposable invention can for example be found in a blood treatment device with a volumetric fluid balancing use, having a divided by a semipermeable membrane into a blood chamber and a filtrate chamber filter. Such extracorporeal blood treatment apparatus is known for example from DE 41 16 178 C1, which is expressly incorporated by reference. If the balancing Disposable is used in such a blood treatment device which Filtratausgleichskammer and the second compensation chamber 6 forms the first equalization chamber 5 the Substituatausgleichskammer, during the first and second inlet channel 17, 15 to filtrate and Substituateinlaßkanal and the first and second outlet port 18, 16 to filtrate - and Substituatauslaßkanal form. The balancing Disposable invention can also be found in an advantageous manner in a device for peritoneal dialysis using cyclically Peritonealdialysieiflüssigkeit can be supplied to or removed from a patient in exact balance-sheet way with. For this purpose, the two supply lines 21, 22 together to form a common inlet line and the two outlet lines 23, 24 are brought together to form a common discharge line, the dialysis fluid is passed through the common inlet pipe alternately in the first and second balancing chamber half 9, 10 and on the common outlet conduit is fed to the peritoneal cavity of the patient. In such a peritoneal dialysis machine advantageously a buffer chamber in the first and a buffer chamber into the second outlet channel is switched. Alternatively, however, a buffer chamber are switched after merging into the common discharge line.

FIG. 2 shows a section through the balancing chamber 4 of the non-fluid filled balancing disposables. The intermediate film 8 with its outer edge welded to the edges of the upper and lower films 1, 2 and in the balance chamber 4 between the outer films freely. Since it can not be in strict compliance with a constant volume due to the elasticity of the plastic, the balancing volume is defined by a fixed outer shape. The balancing Disposable is therefore used in a system slot, which is a component of the blood treatment apparatus. The system insert described in detail later with reference to FIG. 5 has two receiving bodies 25, 26 on each one provided in the area of ​​the balancing volume recess 27.

Figs. 3a and 3b show a section through the between the two receiving bodies 25, 26 of the system insert lying balancing chamber 4 of disposables. The upper and lower receiving body 25, 26 of the system insert is provided with a longitudinal clamping edge 28, 29, which fixes the edge portions of the balancing disposables. If the volume between the upper film 1 and the intermediate film 8 filled with liquid, so with the appropriate opening and closing the inputs and outputs of the balancing chamber 4 8 the other volume between the intermediate film 8 and the lower film 2 is discharged as a result of repression by folding the intermediate foil (Fig. 3b). Thus, the upper and lower films 1, 2 of the disposable to the shells of the receiving body 25, 26 can tightly create, vents 30 are provided in the receiving bodies.

Fig. 4 shows a second embodiment of the balancing disposables. The balancing Disposable shown in Figure 5. Differs from the reference to the FIGS. 1 Disposables described to 3, characterized in that a serpentine channel 31 is formed which opens in the second compensation chamber 6, and enables temperature control of the supplied liquid. The heating of the fluid is carried out by the heaters through means in a corresponding system insert provided heating plates, which are brought into contact with the heating foil of disposables. In order to control and temperature monitoring 4 temperature sensors, not shown, may be provided in Fig., Which can measure the temperature on the surfaces of the two outer sheets 1, 2 in a simple manner. Suitably, a control and a protection sensor downstream of the heating foil is arranged at least. In addition, may be advantageous, a further temperature sensor on Heizfolieneingang.

Fig. 5 shows the unfolded system insert the medical treatment device in plan view, in which the balancing Disposable is inserted appropriately. The upper and lower in its external dimensions the disposable corresponding receptacle body 25, 26 of the system insert are connected to a hinge 44 on their longitudinal sides with each other. The recesses 27 for receiving the balancing chamber halves 9, 10 are in the center of the receptacle body 25, arranged 26th The fixing of the disposable is done with the guide pins 42, which engage in the corresponding openings 43 of the disposables. On both sides of the recesses 27 are in the lower receiving body 26 two parallel guide channels 32, 33 are provided for receiving the inlet and outlet channels 15-18. Further, within the guide channels 32, 33, four plungers 34 are arranged which cooperate with the clamping edges 35, which are located at the height of the plunger 34 in the upper receptacle body 25th The electromagnetically actuated plungers 34 terminal points 20 of the channels of the disposables can be clamped pressure-tight. Laterally next to the plungers 34 and the clamping edges 35 26 inserts 36, 37, 38 for receiving the first- and the second compensation chamber 5, 6 and the buffer chamber 7 are in the lower and upper receiving body 25, are provided. At the bottom of the inserts 37, 38 for the balancing chambers the spring biased pressure plates 39, 40 of the system in the slide-compression means are arranged, with which the compensation chambers 5, 6 of the disposables are pressurized. The function of the clamping means and the compression means is described in DE 41 16 178 C1, which is expressly incorporated by reference. At the bottom of the insert 40 for the buffer chamber 7 is another printing plate 41 is provided. This may be mechanically coupled to the printing plate 39 of first equalization chamber to exert an opposite movement.