Abstract: A gas exchange device (100) with an extracorporeal blood circuit (102) in which a blood pump (110) is connected, with a CO.sub.2 exchange unit (112), and an oxygenator (128), whereby the gas exchange unit (112, 128) is in each case divided by a hydrophilic, water-wet membrane (114, 130) into a blood chamber (116, 132) and a gassing chamber (118, 134) which is under positive transmembrane pressure.

Abstract: A method and apparatus for monitoring the operability of components in a hemodialysis apparatus during dialysis treatment. The dialyzer is isolated from the dialyzing liquid circuit for a time interval during dialysis treatment. During the isolation time interval, the dialyzing liquid circuit pressure is measured and monitored to detect deviations from a mean dialyzate operating pressure. The isolation is repeated periodically, with the time period between isolation intervals dependent upon the ultrafiltration coefficient of the dialyzer. This method may be performed automatically by a microprocessor in the hemodialysis apparatus.

Abstract: The invention concerns a bag to accommodate solid or fluid concentrate which is used to prepare dialysis fluid using a dialysis machine. The bag consists of a bag body and at least one opening, whereby the opening is sealingly surrounded by a plug component (220). In the coupled state with a second plug component (210), the plug component (220) forms a flow connection with the interior of the bag. The plug component also has coupling means (276, 278) which are suitable to be connected with a second complementary plug component (210), which is disposed on the dialysis machine. By means of the plug connector, in the coupled state, a first flow path is formed from the dialysis machine to the interior of the bag and a second flow path is formed back from the interior of the bag to the dialysis machine.

Abstract: In a dialysis apparatus having a dialyzer and a single balance chamber, the internal volume of the balance chamber is preferably at most 2/3 of the volume of the dialysis fluid chamber within the dialyzer. As a result, during the dialysis fluid recirculation cycle, at most 2/3 of the volume of fluid within the dialysis fluid chamber will be replaced by fresh dialysis fluid. Preferably, the duration of the recirculation cycle is approximately equal to the duration of the balance chamber filling cycle.

Abstract: A method for reprocessing dialyzer cartridges used with kidney dialysis machines is provided. The method involves filling the blood and dialysate compartments of the dialyzer with an aqueous solution containing citric acid at a concentration of 1.0-5.0 wt. %, e.g., 1.5 wt. %, and then subjecting the dialyzer to an elevated temperature above 90.degree. C. and below 100.degree. C., e.g., 95.degree. C., for a period of at least 15 hours, e.g., 20 hours. Although citric acid is non-toxic and the temperature used is below the boiling point of water, the process has been found to produce a fully sterilized dialyzer. After reprocessing, the aqueous citric acid solution is preferably left in the dialyzer where it acts as a bacteriostatic agent during storage. Essentially no damage to the dialyzer and, in particular, to its semipermeable membrane results from either the reprocessing or storage procedures.

Abstract: Implantable infusion apparatus comprising a chamber sealed by a septum and having an outlet aperture leading therefrom, to which a catheter tube is connected. A wire anchored in the chamber base projects into the catheter lumen, forming a ring slot whose diameter is smaller than the average size of a punched out particle. The wire thus serves as a particle retention means.

Abstract: A hemodialysis device (10) which features an improved disinfection apparatus. Before disinfection begins, a container (30) of disinfectant (36) is interposed into the dialysis fluid circulation system in place of the dialyzer. The dialysis fluid circulation system is shunted, and the disinfecting solution which is present in this closed circulation system is flushed out of the container (30) and through the entire path of the dialysis fluid, in order to achieve a complete cleaning of the hemodialysis device (10). It is possible to use solid, soluble disinfectant (36) as well as liquid disinfectant.

Abstract: An apparatus for preparing a medicinal solution, in particular dialysis solution, from pulverulent concentrate and water comprises a water source (12) from which a first conduit (14) is led to a container which contains the powder and from which a second conduit (20) into which a first measuring cell (22) and a concentrate pump (24) are connected leads to a mixing point (28). Said mixing point (28) is located in a third conduit (26) which leads from the water source to a consumer; downstream of the mixing point (28) a second measuring cell (30) is provided for monitoring the composition of the finished dialysis solution. Since the two measuring cells (22) and (30) lie in different conduits in which solutions of different composition are conveyed, there is no possibility whatever of confusions between concentrates of the same initial conductivity but different final conductivity after dilution with water.

Abstract: To determine in simple manner the change of the intravascular blood volume during filtration, in the extracorporeal blood circuit (2) of a blood purification apparatus at least one ultrasonic sensor (15) is arranged which is connected to an evaluating unit (18) which is configured in such a manner that at the start of the filtration a first ultrasonic signal is stored and during the filtration the change of the ultrasonic signals is determined. From the change of the ultrasonic signals the change of the hematocrit is determined and from this the change of the intravascular blood volume is deduced.

Abstract: This invention relates to a pressure equalizing vessel for a hemodialysis concentrate. To ensure the supply of concentrate at a constant pressure to the concentrate pump for preparing dialysis fluid, even in cases where a central concentrate supply system is used, the present invention suggests that a cylindrical upright vessel 1 whose lower portion is provided with a concentrate inlet and whose upper portion has arranged thereon a venting means 4 should have inserted thereinto a concentrate suction tube 7 which is equipped with at least one level sensor (FIG. 1).

Abstract: This invention relates to a method for the in-vivo determination of hemodialysis parameters. To carry out hemodialysis with the greatest efficiency and safety, it is inter alia necessary to know the clearance of the dialyzer. To be able to determine the same in vivo, the invention provides a method in which the electrolyte transfer of the dialysis fluid is measured by means of a measuring device at two different predetermined dialysis fluid ion concentrations and the dialysance is determined on the basis thereof, which dialysance is numerically equal to the clearance.

Abstract: The invention is directed to a process and an arrangement for control of blood pumps in an extra-corporeal circuit provided to a single needle arrangement. In order to avoid recirculation, in accordance with the invention it is provided that the arterial and the venous pumps run at an increased throughput rate at the beginning of each pumping phase.

Abstract: The invention concerns a hemodialysis apparatus with a hemodialyser (10), which on the blood side has a blood pump (30) to convey blood from a patient to the dialyser (10) and on the dialysis solution side has a dialysis solution pump (20) to convey dialysis solution to the dialyser. The hemodialysis apparatus has a control device (100) whereby a signal derived from the magnitude of the blood flow is fed to the said device on the input side and whereby the said device gives a signal on the output side as a function of the blood flow in order to adjust the dialysis solution flow. With an automatic control device of this type dialysis concentrate, prepared water and energy can be saved. The predetermined control function can be a linear function.

Abstract: An implantable device for the dosed administration of medicaments to the human body includes a first chamber for storing a medicament and having a refill opening sealed by a pierceable septum and an outlet opening communicating with an outlet catheter, a second chamber separated from the first chamber by a flexible diaphragm which serves to apply pressure to the medicament, and a hollow fiber capillary filter disposed at the outlet opening of the first chamber to act as a filter.

Abstract: An infusion pump system comprising means for measuring internal diameter of an associated pump supply tube formed from a flexible material, such as plastic or rubber. The means for measuring internal diameter may comprise an ultrasound system including at least one transmiter and one receiver, as well as an evaluation unit. Alternatively, a mechanical system may be employed in the form of a counterpressure unit arranged perpendicular to the axis of the supply tube and including a movable plunger and an abutment surface for compression of the supply tube to be measured. A measurement and evaluation unit associated with the counterpressure unit determines the distance traversed by the movable plunger. The internal diameter of the tube may be determined by generating a force-displacement diagram. In accordance with one embodiment, the movable plunger is a pumping rod of a linear peristaltic pump.

Abstract: For the infusion of medicaments and drugs, in particular heparin, into the partial vacuum region of an extracorporeal blood circuit an apparatus is described which replaces the previously used heparin pump and which comprises a supply container in the form of a syringe, a shutoff member, which may be a clamp, disposed in the feed conduit, a means for measuring the reduced pressure or partial vacuum in the extracorporeal circuit and a control means. Said control means is connected to the pressure measuring means and the shutoff member and constructed for periodic opening and closing of the shutoff member in dependence upon the measured partial vacuum and the desired amount of medicament. The apparatus may be used for example in the extracorporeal blood circuit of a dialysis apparatus.

Abstract: A method and a device for ultrafiltration during hemodialysis are described in which ultrafiltrate fluid, before removal from the dialysis circuit, is passed through a balancing device, which is also used as ultrafiltrate pump. For this purpose, a controller controls and actuates inlet, outlet, and dialyzer valves, in such a way that a desired amount of ultrafiltrate, corresponding to the filling volume of a balancing chamber or a multiple thereof, is introduced to the discharge through the balancing chamber. In order to carry out continuous ultrafiltration during hemodialysis, a predetermined amount of air is introduced to the dialysis fluid flow circuit through an air separator and is then pumped off during hemodialysis so that a corresponding amount of ultrafiltrate is obtained.

Abstract: An apparatus is described for dosed continuous simultaneous infusion of several solutions or medicaments which are arranged in a plurality of containers (25, 26) or syringes (3, 4). From said containers (25, 26) or syringes (3, 4) connecting conduits or tubes (18-21) lead which are connected via a junction piece (27) to a patient conduit (23). In each of the connecting conduits (18-21) a pump (1-4) and a clamp (5-8) are provided which are each controlled via a central processing unit (17). Downstream of said actuating means in the patient conduit (23) a flow element (14) is provided which on detection of a flow stop causes the control means (17) to deactivate the entire apparatus.

Abstract: An apparatus for making mixtures of pharmaceutical liquids has a plurality of supply vessels for the mixture components. The supply vessels are connected via a tubing system to a container to be filled with the mixture. The tubing system includes a drip chamber. The container is arranged in a vacuum chamber. The vacuum chamber has a temperature sensor and a pressure sensor which are connected to a control device. For preparing the mixture, and using the law of the general gas equation, each mixture component is sequentially drawn, via the drip chamber, to the container by the vacuum in the chamber. The pressure and temperature in the vacuum chamber are monitored so that when the particular predetermined volume of one component is reached in the container, the supply vessel for that component is closed off, and the supply vessel for another component is opened.

Abstract: The tapped voltage representing the displacement and duration of a potentiometer in a joystick-type actuating element is applied to an analog to digital converter and the converted digital value is fed to preset inputs of a presettable digital counter which is set at its counting inputs by a clock generator. The overflow output of the presettable counter is connected to a load input of the presettable counter and to an up/down counter which controls a display or the like via decoding and driver circuits. A subtracting circuit is provided to subtract a preselected value from the converted digital value in order to provide a dead zone for a preselected range of the potentiometer.