Infusion bag and infusion system

IS 2 365 697 T3

DESCRIPTION

Infusion bag and infusion set

TECHNICAL FIELD

The present invention relates to an infusion or infusion bag according to the preamble of claim 1, and an infusion system according to the preamble of claim 10. In particular, the invention relates to an infusion bag and a infusion systems that exhibit a high degree of leak tightness when medically effective substances are delivered to the infusion bag.

BACKGROUND OF THE INVENTION

Infusion bags are used for intravenous delivery of medically effective fluids and substances to humans or animals. For this reason, the infusion bag is provided with at least one outlet channel through which a fluid can flow to a connecting device such as, for example, a cannula. When preparing the fluids to be delivered to the body from the infusion bag, it is common for medically effective substances to be delivered to a pre-sealed infusion bag that is filled with a transport fluid, usually in the form of a solution of sodium chloride or a glucose solution. In certain cases, medically effective substances are harmful to people other than the patient who has been prescribed predetermined doses as a result of an indication for a specific disease. This is particularly the case for long-term exposure, which can happen to medical personnel when handling and preparing drugs over a long period of time. For example, this happens when infusion bags containing cytotoxins, antibiotics, and antiviral drugs are prepared. For this reason, there are special preparations that require preparation in safety cabinets and the use of personal protective equipment, which implies that handling cannot take place without using these protective measures and devices. As a rule, the preparation is carried out by means of the injection of medically effective substance through a membrane provided in connection with an inlet channel provided through the wall of the infusion bag. When this type of injection is performed, leakage often occurs when the piercing needle is withdrawn after it has penetrated the membrane. As the piercing needle is often rough, a major leak can occur. A droplet of medically effective substance will be transported from the tip of the cannula to the area surrounding the perforation in the membrane, where the leak occurs. An infusion bag according to the preamble of claim 1 is known from US-A-4,564,054.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to reduce the risk of exposure to medically effective substances when preparing infusion bags. A second object is to provide infusion bags that allow brewing to take place at any optional location without any leakage occurring, which reduces the staff resources required for brewing, reduces brewing time, and also provides advantages of treatment and reduces the need for personal protective equipment and special peripheral equipment in the form of safety cabinets. The above-mentioned objects are achieved by an infusion bag according to the characterizing part of claim 1 and an infusion system according to the characterizing part of claim 8, by means of the infusion bag which is provided with an input channel, provided in connection with an integrated communication member having an opening in which a first flexible membrane is provided in said opening to be accessible to a second flexible membrane provided on a connection member, and in which said communication member exhibits means to hold said second flexible membrane with a pressure against said first membrane, so that the formation of droplets on the surface of the first membrane is prevented, wherein the occurrence of leakage after injection is prevented.

DESCRIPTION OF THE DRAWINGS

An embodiment of the invention will be described in greater detail with reference to the accompanying drawings, in which:

Fig. 1 shows a side view of an infusion bag

Fig. 2 shows a first embodiment of a communication member, and

Fig. 3 shows a second embodiment of a communication member.

PREFERRED EMBODIMENT

Fig. 1 shows a side view of an infusion bag which is generally indicated 1. The infusion bag 1 exhibits an internal space 2, which is surrounded by walls 3 of a preferably flexible material. According to an embodiment of the invention which is shown in fig. 1, a front wall 3a is connected to a rear wall 3b along the

ES 2 365 697 T3 long of two opposite side edges 4, 5, an upper edge 6 and a lower edge 7. The connection can be achieved by means of welding, or, alternatively, gluing or gluing. In this way, the internal space 2 is formed between the joined edges 4-7. However, the invention is not limited to a special design of an infusion bag, but can be manufactured in any way that is well known to the person skilled in the art. An outlet channel 8 and an inlet channel 9 are provided through a wall of the bag 1. Preferably, said channels are provided in connection with the lower edge 7 of the bag, which is preferably reinforced along the lower edge 7 to give stability to output channel 8 and input channel 9. In one embodiment of the invention, this has been achieved by means of a tube 10 that has been inserted and secured between the front wall 3a and the rear wall 3b to form an outlet channel.

eight. When assembled, the tube can already be provided with means to seal the channel until use. These sealing means may be of any type well known to one of ordinary skill in the art, alternatively the tube 10 may be hermetically sealed after it has been assembled.

Furthermore, the inlet channel 9 has been formed within a communication member 11. The communication member is integrated with the walls of the infusion bag. This means that the communication member is permanently attached to the walls, either by means of the communication member that is in one piece with the walls, or by means of the communication member that has been fixed by means of welding, gluing, or another permanent union. Communication member 11 exhibits an opening 12 through which a first flexible membrane 13 is provided in an accessible manner, wherein a second flexible membrane (not shown) provided on a connecting member can be pressed against the first membrane. flexible. Inlet channel 9 extends through communication member 11. Membrane 13 forms a seal that prevents liquid from passing from inside the infusion bag to the environment. Furthermore, the communication member 11 comprises means for maintaining said second flexible membrane with a pressure against said first membrane. These means can be constituted, for example, by an elastic snap lock having an elastic finger engaging in a recess. The finger or recess may be provided on the communication member, alternatively, the member as well as the recess may be provided on both the communication member and the connecting member. In a preferred embodiment, which is shown in FIG. 3, these fingers surround said opening 12 and are aligned along the axis of symmetry of the opening. According to a preferred embodiment, said holding means comprise first guide members 14 which are adapted to interact with corresponding second guide members (not shown) on said connecting member. Furthermore, said first guide members exhibit a bearing surface that forms an angle with a general plane of an axial extension of said opening, wherein said connecting member is intended to be transported along said axial extension relative to the member of communication through rotation.

Figs. 2 and 3 show alternative embodiments of the communication member 11. In the embodiment shown in FIG. 2, the communication member 11 is constituted by a substantially cylindrical body having an axial through channel 9. The cylindrical body exhibits a first part 16, which is intended to be permanently integrated with the walls of the infusion bag. Furthermore, the communication member exhibits a second part 17 that is adapted to be connected to a connection member (not shown). In a preferred embodiment, the diameter of the second part 17 exceeds the diameter of the first part, in which a good seal between walls and communication member is achieved while the communication member is easy to handle relative to a connecting member. In the embodiment shown in FIG. 2, the membrane is surface mounted in connection with the first end surface 18 of the communication member. The membrane is fixed in the communication member in a way well known to the person skilled in the art, for example by being fixed in a coaxially designed groove that is provided in the channel 9. By means of this design, the communication member is adapted to a connecting member that is coaxially positioned outside the communication member.

In the embodiment shown in FIGS. 1 and 3, the membrane is positioned in an opening 12. In this embodiment, the communication member is adapted to a connecting member that is coaxially positioned against the inner walls 20 of the opening. For this reason, aperture 12 is designed as a cylindrical recess and exhibits such guide members. The aperture preferably exhibits a diameter that exceeds the diameter of the channel, preferably the diameter of the aperture 12 is at least twice as large as the diameter of the channel 9. Furthermore, the embodiment according to FIG. 3 exhibits several fingers disposed on the first end surface 18 of the communication member. These fingers extend outward from the surface in an axial direction. In a preferred embodiment of the invention, the fingers are beveled in a direction away from this surface, in which a conical guide for the connecting member, to center the latter relative to the communicating member, can be achieved.

In order to ensure that the blocking of said first and second membranes takes place with a correct pressure between the two membranes, said guide members exhibit an end stop which is intended to restrict the movement of said connecting member towards said membrane by means of of a part of the connecting member that is pressed against said end stop.

In this context, "correct pressure" means that said locking means locks the connecting member against the

ES 2 365 697 T3 communication member when said first and second membranes have been pressed together to a pressure that exceeds the elastic limit of said membranes. This means that the membranes exhibit the same properties on the surfaces that have been pressed together as on another optional cross section through the membranes, which implies that the liquid cannot be pressed through the contact surfaces of the membranes. Such a property is obtained when said first and second membranes have been pressed together to a pressure exceeding 150 kPa. According to a preferred embodiment, this elastic limit point is reached by said locking means that locks the connecting member against the communication member when said connecting member has been tightened at least 1.4 mm in a direction towards said first membrane after having established contact between said first membrane and said second membrane.

A series of tests have been carried out on leak-proof fluid transfer systems, comprising a connecting member and a communication member exhibiting an inlet channel, a first flexible membrane that separates said inlet channel from an opening of the communication member, and means for maintaining a second membrane provided on the connecting member with pressure against said first membrane, by measuring the clamping force to be exceeded in order to clamp the membranes together until a sufficient seal is achieved.

In these tests, a sufficient hermetic seal has been achieved with a compression within the range of 2.9-11.1 N, with a mean value of 7.6 N and a standard deviation of 1.7 N. This means that a preferred range is between 5.9 and 9.3 N. The deformation length has been measured to be between 1.4 and 2.0 mm, preferably 1.7 mm. The diameter of the membrane is 5mm and the material of the membrane is a kind of elastomer. A more correct measure of when sufficient sealing will be achieved is the pressure with which the membranes make contact with each other. In a preferred embodiment, with the aforementioned forces and diameter of the membrane, a sufficient seal is obtained when the contact pressure exceeds 150 kPa. As the device runs the risk of being destroyed if it is subjected to excessively large contact forces, the contact pressure should be restricted as much as possible. In the same evaluation, it has been found that a sufficient seal without any risk of failure is obtained with contact forces of up to 11.1 N which corresponds to 565 kPa. Preferably the contact pressure is within the range of 300-473 kPa.