Abstract: A system for measuring at least one fluid characteristic at various stages within a sorbent system that has a sorbent cartridge that has at least one material layer and at least one fluid passageway in at least one location in the sorbent system to provide a diverted sample stream from the various stages. At least one fluid characteristic of the diverted sample stream is measured.

Abstract: Systems, methods, and apparatus for gastric pressure relief, flow regulation, location, gastric residual volume, a placement reminder, bidirectional fluid flow markings, reintroducing gastric material, collection reservoir raising, collection reservoir hanging, a drain port, setting tube length, and vent membranes. A gastric pressure relief system is used in connection with an enteral feeding system, which includes a feeding container, administration tubing and a delivery tube, where the gastric pressure relief system is interposed between the administration tubing and the delivery tube. The gastric pressure relief system includes a collection reservoir with a gas vent to ambient atmosphere, relief tubing secured to both the collection reservoir and a multi-way connector. The multi-way connector joins the administration tubing to the relief tubing and a delivery tube at a point below a patient's stomach, which is designated on a placement reminder apparatus.

Abstract: A disposable cartridge for use in a hemodialysis machine has a blood flow path for carrying a volume of blood to be treated in a dialyser and a dialysate flow path, isolated from the blood flow path, for delivering a flow of dialysate solution through the dialyser. The cartridge is received in an engine section of the machine. The engine section has first and second platens which close when the cartridge is inserted to retain the cartridge. Actuators and sensors arranged on the second platen control operation of the cartridge.

Abstract: Systems, methods, and apparatus for gastric pressure relief, flow regulation, location, gastric residual volume, a placement reminder, bidirectional fluid flow markings, reintroducing gastric material, collection reservoir raising, collection reservoir hanging, a drain port, setting tube length, and vent membranes. A gastric pressure relief system is used in connection with an enteral feeding system, which includes a feeding container, administration tubing and a delivery tube, where the gastric pressure relief system is interposed between the administration tubing and the delivery tube. The gastric pressure relief system includes a collection reservoir with a gas vent to ambient atmosphere, relief tubing secured to both the collection reservoir and a multi-way connector. The multi-way connector joins the administration tubing to the relief tubing and a delivery tube at a point below a patient's stomach, which is designated on a placement reminder apparatus.

Abstract: Method for separating a volume of composite liquid into at least a first component and a second component including centrifuging a separation bag containing a volume of composite liquid and a volume of gas so as to sediment at least a first component and a second component separation bag; displacing a volume of hydraulic fluid against the separation bag to cause a transfer of at least one fraction of the content of the separation bag into at least one component bag connected to the separation bag; determining the volume of hydraulic fluid displaced and determining the volume of the composite liquid or the transferred components from the determined volume of displaced hydraulic fluid.

Abstract: A medical apparatus comprises a control system allowing storage of a number of shaping profiles. Each shaping profile is stored as a plurality of pairs, including a shaping profile reference value and a time interval value. The reference value is represented as fraction, for instance a percentage, of the total weight loss the apparatus should achieve at the end of a treatment time. Each time interval value is represented either as fraction of the total treatment time or as a prefixed actual time interval. The control system calculates the actual weight loss rate versus time profile based on the desired total weight loss, on the desired total treatment time as well as on selected desired shaping profile.

Abstract: The invention relates to a method for monitoring an arrangement for determining a concentration of an analyte in a body fluid. The determination of the concentration of the analyte by means of the arrangement involves a procedure in which the analyte from the body fluid passes through an interface and is transported in a stream of liquid into a flowmeter chamber, in which a measurement is carried out to determine the concentration of the analyte. The evaluation of the measurement takes place in a signal processor. The monitoring of the arrangement comprises the following steps: measurement of measured values of at least two correlated system parameters of the arrangement by means of a sensor system, and comparison of the measured values with limit values stored for each of the system parameters in a storage unit, to obtain a combination of at least two comparison results.

Abstract: A multipurpose hemofiltration system and method are disclosed for the removal of fluid and/or soluble waste from the blood of a patient. The system continuously monitors the flow rates of drained fluid, blood, and infusate. When necessary, the pumping rates of the infusate, drained fluid and blood are adjusted to remove a preselected amount of fluid from the blood in a preselected time period. A supervisory controller can monitor patient parameters, such as heart rate and blood pressure, and adjust the pumping rates accordingly. The supervisory controller uses fuzzy logic to make expert decisions, based upon a set of supervisory rules, to control each pumping rate to achieve a desired flow rate and to respond to fault conditions. An adaptive controller corrects temporal variations in the flow rate based upon an adaptive law and a control law.

Abstract: The invention relates to a method for monitoring the supply of substitution liquid during an extracorporeal blood treatment and to an extracorporeal blood treatment unit equipped with a device for monitoring the supply of substitution liquid. The monitoring of the supply of substitution liquid is based on the measurement of pressure waves, which are generated by the substitution liquid pump, in the extracorporeal blood circulation system. A disturbance in the supply of substitution liquid is inferred when the amplitude of the pressure waves exceeds a predetermined limit value. The amplitude of the pressure waves is preferably monitored in the venous blood line.

Abstract: A number of improvements relating to methods and apparatuses for kidney dialysis are disclosed.

Abstract: A number of improvements relating to methods and apparatuses for kidney dialysis are disclosed. These include methods such as supplying a dialysis machine including a touch screen interface to a machine user and supplying to the machine user accessory devices to be used with the dialysis machine in operation.

Abstract: A first flow path is defined within a first panel that forms a part of an extracorporeal fluid circuit. A second flow path is defined within a second panel that also forms a part of the extracorporeal fluid circuit. The first and second panels are oriented in a fluid processing cartridge for mounting as an integrated unit on a fluid processing machine and for removal as an integrated unit from the fluid processing machine.

Abstract: In a blood dialysis system including a source of substitution fluid (10) and a blood dialysis machine, a hemodiafiltration system having a first dialyzer (1) including a first blood compartment (4) having a first blood inlet which receives blood to be cleaned and a first blood outlet which discharges partially diafiltered blood and a first dialysate compartment (5) having a first dialysate inlet and a first dialysate outlet, means (8) for mixing the partially diafiltered blood with substitution fluid from the source to obtain a blood/substitution fluid mixture, and a second hemofilter (2) including a second blood compartment (11) having a second blood inlet which receives the blood/substitution fluid mixture and a second blood outlet which discharges filtered blood and a second permeate compartment (12) having a second permeate outlet.

Abstract: A method for preparing a medical liquid from a liquid, such as water, and two concentrated solutions comprises the following steps: circulating the liquid in a conduit (15), at a flowrate Q0; injecting into the conduit (15), at a flowrate Q1, a first concentrated solution containing a first ionic substance A and a second ionic substance B, the ionic substances A and B having, respectively, in the first concentrated solution, a concentration [Asol] and a first concentration [B1sol]; injecting into the conduit (15), at a flowrate Q2, a second concentrated solution containing the first ionic substance A and the second ionic substance B, the first ionic substance A having, in the second concentrated solution, the same concentration [Asol] as in the first concentrated solution, and the second ionic substance B having, in the second concentrated solution, a second concentration [B2sol] different than the first concentration [B1sol] in the first concentrated solution; regulating the injection flowrate Q1 and the

Abstract: This invention provides a method and apparatus for a hemodiafiltration delivery module that is used in conjunction with a UF controlled dialysis machine to enable hemodiafiltration therapy to be performed. The advantage is that one can fully utilize a current functioning dialysis machine to perform a hemodiafiltration therapy as opposed to purchasing a completely new machine that offers this capability.

Abstract: A method of setting up a dialysis treatment in a dialysis machine (1) provided with a device (6) for setting up the dialysis treatment, possessing a microprocessor (11), a data input (12, 13) and a screen (13), comprises the steps of: supplying a group of functions (U(t, P); C(t, P)) of a quantity (U; C) that is characteristic of the dialysis treatment as a function of time (t) and of a parameter (P) correlated with intermediate values (U1, C1) of each function (U(t; P); C(t; P)) of the group; selecting a subset of the group of functions (U(t, P); C(t; P)) imposing boundary conditions (U0, TWL, DT; C0, Cf, DT; C0, CS, DT) that are characteristic of a particular therapy; assigning values to the parameter (P) and displaying the curves corresponding to the functions (U(t, P); C(t, P)) of the subset and to the respective values assigned to parameter (P); and selecting one of the functions ((U(t, P); C(t, P)) of the subset on the basis of the images of the curves.

Abstract: A method of setting up a dialysis treatment in a dialysis machine may include the steps of determining conditions of a dialysis treatment adapted to a specific patient, determining a first function (U(t)) of a first quantity (U) characterizing the dialysis treatment as a function of time (t), and determining a second function (C(t)) of a second quantity (C) characterizing the dialysis treatment. The first function (U(t)) satisfying the conditions of the dialysis treatment and corresponding to a curve having a defined shape. The second function (C(t)) is correlated with the first function (U(t)) by constants (M, N) determined experimentally and the second function (U(t)) corresponding to a curve having a shape of the same kind as the shape as the first curve.

Abstract: An extra-corporeal blood purification device includes a blood filter, and elements for measuring at least one parameter affected by filter resistance to liquid flow, elements for determining at least a threshold value of the parameter, elements for comparing the parameter with the threshold value, exchange control elements for calculating the distribution between the respective flow rates through connecting ducts, capable of reducing the difference between the value of the measured parameter and the threshold value.

Abstract: A property of unconnected first and second fluid flows is matched, such as, but not limited to, matching the flow rate of the replacement water stream with the waste water stream in kidney dialysis. The first and second flow paths are interconnected so substantially the same flow from the first flow source encounters a first flow transducer which is in the first flow path and a second flow transducer which is in the second flow path. Transducer readings are taken for various identical values of the property of the first fluid flow. Then the first and second flow paths are disconnected, and the property, such as but not limited to flow rate, of one of the fluid flows in one of the flow paths is controlled using transducer readings and the previous interconnected-path transducer readings to match the property in the two flows. In one example, the transducers are uncalibrated transducers.

Abstract: A flow rate of unconnected first and second fluid flows is matched, such as, but not limited to, matching the flow rate of the replacement water stream with the waste water stream in kidney dialysis. The first and second flow paths are interconnected so substantially the same flow from a positive displacement pump in the first path encounters a flow-rate transducer in the second path. Transducer readings are taken for various values of the controllable pump speed of the pump. Then, the first and second flow paths are disconnected, a transducer reading is taken, and the flow rate of the fluid flow in the first flow path is controlled by controlling the pump speed using the value of the pump speed from the previous interconnected paths which corresponds to the value of the transducer reading from the previous interconnected paths which matches the transducer reading for the disconnected paths.

Abstract: A hemofiltration machine at a local treatment site is linked to a remote main data base server by a local transmitting/receiving device. The machine acts as a satellite of the main data base server. The machine performs specified therapy tasks while monitoring basic safety functions and providing the person at the treatment location notice of safety alarm conditions for resolution. Otherwise, the machine transmits procedure data to the main data base server. The main data base server relieves the machine from major data processing tasks and related complexity. The main data base server, remote from the machine, controls the processing and distribution of the data, including the flow of information and data to the person undergoing therapy.

Abstract: A haemofiltration machine designed to work with a haemofilter comprises two compartments separated by a semipermeable membrane, one compartment having an inlet connected to a withdrawing tube for taking blood from the patient and an outlet connected to a blood return tube, the other having an outlet connected to a tube for removing used liquid.

Abstract: A method of supplying ready-to-use dialysis fluid in a machine for extracorporeal blood treatment, is described, said machine having, in addition to a dialyzer, at least one sterile filter divided by a microbe-retaining membrane into a first and second chamber. The temperature and/or conductivity of the dialysis fluid flowing through the sterile filter is monitored. To prevent dialysis fluid whose temperature and/or conductivity does not correspond to a preset temperature and/or conductivity value from flowing out of the second chamber of the sterile filter into the dialyzer after rinsing off the membrane of the sterile filter, the dialysis fluid flowing out of the sterile filter is first removed into the drain through a bypass line until the proper values are established. Only then is the dialyzer connected to the dialysis fluid path. In addition, the invention relates to a machine for extracorporeal blood treatment with a device for supplying ready-to-use dialysis fluid.

Abstract: To increase the safety of an extracorporeal blood treatment machine which has control of the ultrafiltration rate as a function of the blood volume of the patient, the ultrafiltration rate UFR(t) during the treatment is monitored in a safety device. The safety device has a computer unit for determining an upper limit for the ultrafiltration rate UFRlim from the predetermined total ultrafiltrate volume UFVtot and the predetermined treatment time UFT. The safety device also has a monitoring unit with which the ultrafiltration rate is limited to the upper limit determined by the computer unit so that any risk to the patient is prevented even in the case of faulty blood volume control.

Abstract: An extracorporeal fluid circuit for performing hemofiltration defines within a flexible panel a flow channel that is free of an air interface. The flexible panel includes an in-line sensor region through which fluid pressure in the flow channel can be measured by an external sensor. The systems and methods enable sensing fluid pressure through the in-line sensor region using the external sensor. The flow channel can convey, e.g., waste from the hemofilter or replacement fluid for return to the individual.

Abstract: A multipurpose hemofiltration system and method are disclosed for the removal of fluid and/or soluble waste from the blood of a patient. The system and method are equally applicable to adult, pediatric and neonatal patients. In one embodiment, the system continuously monitors the weight of infusate in a first reservoir and drained fluid in a second reservoir and compares those weights to corresponding predetermined computed weights. When necessary, the pumping rates of the infusate, drained fluid and blood are adjusted in order to achieve a preselected amount of fluid removal from the patient's blood in a preselected time period. Application of this system and method provide repeatable and highly precise results. Alternatively, predetermined patient parameters can be monitored and the adjustment of pumping rates may be responsive to these monitored parameters.

Abstract: A method of hemodiafiltration including the steps of supplying a blood inflow, diafiltering the blood inflow using a first non-isosmotic dialysate fluid to provide a partially diafiltered blood outflow, mixing the partially diafiltered blood outflow with a substitution fluid to provide a blood/substitution fluid mixture, and diafiltering the blood/substitution fluid mixture using a second non-isosmotic dialysate fluid.

Abstract: In a blood dialysis system including a source of substitution fluid and a blood dialysis machine, a hemodiafiltration system comprises a first dialyzer including a first blood compartment having a first blood inlet which receives blood to be cleaned and a first blood outlet which expels partially diafiltered blood and a first dialysate compartment having a first dialysate inlet and a first dialysate outlet, means for mixing the partially diafiltered blood with substitution fluid from the source to obtain a blood/substitution fluid mixture, and a second dialyzer including a second blood compartment having a second blood inlet which receives the blood/substitution fluid mixture and a second blood outlet which expels diafiltered blood and a second dialysate compartment having a second dialysate inlet and a second dialysate outlet.

Abstract: A method for priming a hemodialyzer is disclosed. Hemodialyzer comprises a dialysate compartment, a blood compartment, and a dialysis membrane separating the dialysate and blood compartments. The method comprises the steps of delivering a liquid to a dialysate inlet of the dialysate compartment at a first volumetric delivery rate, passing the liquid through the dialysate compartment from the dialysate inlet to a dialysate outlet of the hemodialyzer and delivering the liquid from the dialysate outlet at a second volumetric delivery rate that is less than the first volumetric delivery rate so as to cause a net flow of the liquid from the dialysate compartment to the blood compartment through the dialysis membrane.

Abstract: An apparatus and method for hemodiafiltration are disclosed. The apparatus includes a first dialyzer cartridge containing a semi-permeable membrane that divides the dialyzer into a blood compartment and a dialysate compartment. Fluid discharged from the blood compartment of the first dialyzer cartridge is mixed with sterile substitution fluid to form a fluid mixture and the mixture enters a second dialyzer cartridge. The second dialyzer cartridge contains a second semi-permeable membrane which divides the second dialyzer cartridge into a blood compartment and a dialysate compartment. Hemodiafiltration occurs in both cartridges.

Abstract: A multipurpose hemofiltration system and method are disclosed for the removal of fluid and/or soluble waste from the blood of a patient. The system and method are equally applicable to adult, pediatric and neonatal patients. In one embodiment, the system continuously monitors the weight of infusate in a first reservoir and drained fluid in a second reservoir and compares those weights to corresponding predetermined computed weights. When necessary, the pumping rates of the infusate, drained fluid and blood are adjusted in order to achieve a preselected amount of fluid removal from the patient's blood in a preselected time period. Application of this system and method provide repeatable and highly precise results. Alternatively, predetermined patient parameters can be monitored and the adjustment of pumping rates may be responsive to these monitored parameters.

Abstract: Methods and apparatus are disclosed for monitoring an infusion pump utilized in a dialysis machine for hemodiafiltration or hemofiltration. The apparatus includes a first flow circuit for a dialysis solution, including a flow meter, a second flow circuit for blood, the dialysis apparatus including a first chamber connected to the first flow circuit, a second chamber connected to the second flow circuit, and a semipermeable membrane separating the first and second chambers, a third flow circuit for withdrawing an infusion solution from the first flow circuit and delivering the infusion solution to the second flow circuit, the third flow circuit including the infusion pump, and a first valve for disconnecting the dialysis apparatus from the first flow circuit and connecting the infusion pump in series with the flow meter in the first flow circuit whereby the expected flow through the infusion pump can be compared with the measured flow through the flow meter.

Abstract: A method for flushing and filling of an extracorporeal blood circulation system of a dialysis machine is disclosed. The machine has a dialyzer, a separate dialysis liquid circuit flowing through a dialysate side of the dialyzer with the extracorporeal blood circulation system flowing through a blood side of the dialyzer for removal of impurities from the blood and the dialysate and blood sides of the dialyzer separated by a hemodialyzer membrane. The method comprises the steps of transporting dialysis liquid from the dialysis liquid circuit in the dialysate side of the dialyzer through the hemodialyzer membrane into the blood side of the dialyzer and the extracorporeal blood circulation system to flush and fill the system and conducting a dialysis treatment.

Abstract: A device and method are described to determine the concentration of a substance in blood flowing through a blood chamber of a dialyzer during extra corporeal blood treatment. The flow rate of dialysate flowing through the dialysate chamber of the dialyzer is reduced to a value at which the concentration of the substance at the outlet of the dialysate chamber is essentially the same as the concentration of that same substance in the blood at the inlet of the blood chamber. The concentration measurement can be carried out without interrupting the flow of dialysate.

Abstract: A sampling system for a blood treatment circuit is disclosed, and is designed to collect a sample representative of all waste liquid discharged from a blood treatment apparatus during a treatment session. The circuit includes a feed line for supplying fresh treatment liquid to the blood treatment apparatus and a discharge line for evacuating waste liquid. A withdrawal line connects the discharge line to a collecting container, and a flow meter in each of the discharge line and the withdrawal line measures liquid flow. A controllable flow restrictor such as a valve is provided in the withdrawal line. A controller selectively opens the flow restrictor each time a predetermine volume is measured in the discharge line and closes the flow restrictor each time another predetermined volume is measured in the withdrawal line.

Abstract: Blood from a patient is treated extracorporeally by any selected one of a plurality of predetermined treatments. Each of the treatments involves the flow of blood from the patient into a primary chamber of a filtration unit, past a semipermeable membrane located in the filtration unit which separates the primary chamber from a secondary chamber of the filtration unit, out the filtration unit and back to the patient. A replacement fluid is selectively and controllably added to the blood, as required for the selected treatment. A secondary fluid is controllably and selectively introduced into the secondary chamber of the filtration unit for controllably collecting material passing across the semipermeable membrane from the blood or for supplying material to pass across the semipermeable membrane into the blood as required for the selected treatment. Materials are removed from the secondary chamber and collected in accordance with the selected treatment.

Abstract: A hemodialysis system includes the following: a dialysate handling unit for providing dialysate to the patient. This unit includes a hemodialysis solution pump and apparatus for monitoring hemodialysis solution safety such as a conductivity tester. Additionally a solution heater and appropriate conventional controls can be provided, as well as a proportioning system, an ultrafiltration measuring unit, and other known apparatus for handling dialysis solution. A blood handling unit is also provided, which includes a membrane dialyzer and holder, a blood pump, blood flow tubing and safety equipment for monitoring blood flow as it is pumped through the arterial/venous blood conduit set tubing from the patient, through the membrane dialyzer, and back to the patient. A first conduit is present for conveying fresh dialysate from the dialysate handling unit to the blood handling unit (or directly to the membrane dialyzer).

Abstract: In a device for providing a substituate to a device for removing toxic substances from the blood which employs volumetric balancing of the fluid, an equalization chamber (11, 20) communicates with first and second inlet lines (9, 18) respectively, of a balancing chamber (14). Moreover, a buffer chamber (23) communicates with the first and/or second outlet line (15, 22) of the balancing chamber (14). The volume prevailing in the buffer chamber (23) that communicates with the first or second outlet line (15 or 22) can be so varied that the volume expands when the second or first equalization chamber (20 or 11) is emptied, and is reduced when the second or first equalization chamber is filled. As a result, the discontinuous pulse is smoothed on the outlet side of the balancing chamber.

Abstract: A method and a device for determining hemodynamic parameters during an extracorporeal hemotherapy, in which the blood arrives via the arterial branch (20) of the extracorporeal circuit (9) of the hemotherapeutic device (7), which is in fluid communication with arterial section (21) of a fistula (6), into dialyzer (10) or into a filter of the hemotherapeutic device and is recirculated via the venous branch (22) of the extracorporeal circuit (9), which is in fluid communication with venous section (23) of fistula (6). The temperature T.sub.A prevailing in the arterial branch (20) of the extracorporeal circuit (9) is measured under a changing blood flow, the temperature T.sub.V of the venous branch (22) of the extracorporeal circuit being kept constant. From the determined value pairs of the arterial temperature T.sub.A and of the extracorporeal blood flow Q.sub.B, those parameters of a predetermined function T.sub.A (Q.sub.

Abstract: An improved on-line, real time hemodialysis monitoring system for hemodialysis treatment, quantitates the rate and amount of a constituent, such as urea, removed during the hemodialysis treating by measuring the constituent concentrations as a function of time in the spent dialysate effluent from a hemodialysis machine. A quantity of the spent dialysate effluent is removed from the dialysate effluent waste line periodically for testing. A urea concentration time profile can be analyzed to determine the urea removal, KT/V, URR, SRI, and normalized protein catabolic rate (nPCR) indices. The hemodialysis monitoring system preferably can obtain a dialysate sample equilibrated with the blood prior to the start of a hemodialysis treatment.

Abstract: The invention relates to a means for determining hemodynamic parameters, such as cardiopulmonary recirculation, fistula flow and cardiac minute output during an extracorporeal blood treatment, in which blood is conducted to a dialyzer (3) by way of arterial branch (8, 8') of extracorporeal path (2) which is fluidly connected to a segment (9, 12) of a fistula (10), then returned by way of venous branch (11, 11') of the extracorporeal path which is fluidly connected to the other segment (12, 9) of the fistula. The hemodynamic parameters are determined by two recirculation fraction measurements taken in quick succession and which are performed automatically by the apparatus before and after the blood flow is reversed. In a computer-memory unit (22) cardiopulmonary recirculation is calculated based on the recirculation fraction during normal blood flow together with the recirculation fraction during reversed blood flow.

Abstract: A hemodialysis system comprises the following: a dialysate handling unit for providing dialysate to the patient. This unit comprises a hemodialysis solution pump and apparatus for monitoring hemodialysis solution safety such as a conductivity tester. Additionally a solution heater and appropriate conventional controls can be provided, as well as a proportioning system, an ultrafiltration measuring unit, and other known apparatus for handling dialysis solution. A blood handling unit is also provided, which comprises a membrane dialyzer and holder, a blood pump, blood flow tubing and safety equipment for monitoring blood flow as it is pumped through the arterial/venous blood conduit set tubing from the patient, through the membrane dialyzer, and back to the patient. A first conduit is present for conveying fresh dialysate from the dialysate handling unit to the blood handling unit (or directly to the membrane dialyzer).

Abstract: Apparatus for monitoring flow of a dialysis fluid through a dialyzer is disclosed including a computer for calculating the flow rate of the dialysis fluid into and out of the dialyzer based on the formula P-P.sub.O =k*Q.sup.n in which P is the pressure in the dialysis fluid between a throttle and a pump either upstream or downstream of the dialyzer, P.sub.O is the pressure in the dialysis fluid on the opposite side of the throttles from the pump, k is a characteristic coefficient for the throttle, Q is the flow of the dialysis fluid through the throttle, and N is a characteristic exponent for the throttle, and the apparatus includes microprocessor for calculating the values of k and P.sub.O prior to use and for calculating the value of P.sub.O during use of the dialyzer. Methods for carrying out such monitoring are also disclosed.

Abstract: Methods for measuring the effect of dialysis treatments are disclosed in which a fraction of the used dialysis fluid is extracted downstream of the dialyzer for analysis of at least one substance such as urea, and in which the fraction of dialysis fluid is extracted through a branch conduit containing a pump. In accordance with this method, the total amount of used dialysis fluid is measured and the concentration of that substance in the extracted fraction is measured, and the total amount of that substance removed from the patient can then be calculated from these values. This invention is preferably intended for use in connection with hemodialysis, hemofiltration and hemodiafiltration.

Abstract: Blood from a patient is treated extracorporeally by any selected one of a plurality of predetermined treatments. Each of the treatments involves the flow of blood from the patient into a primary chamber of a filtration unit, past a semipermeable membrane located in the filtration unit which separates the primary chamber from a secondary chamber of the filtration unit, out the filtration unit and back to the patient. A replacement fluid is selectively and controllably added to the blood, as required for the selected treatment. A secondary fluid is controllably and selectively introduced into the secondary chamber of the filtration unit for controllably collecting material passing across the semipermeable membrane from the blood or for supplying material to pass across the semipermeable membrane into the blood as required for the selected treatment. Materials are removed from the secondary chamber and collected in accordance with the selected treatment.

Abstract: Blood from a patient is treated extracorporeally by any selected one of a plurality of predetermined treatments. Each of the treatments involves the flow of blood from the patient into a primary chamber of a filtration unit, past a semipermeable membrane located in the filtration unit which separates the primary chamber from a secondary chamber of the filtration unit, out the filtration unit and back to the patient. A replacement fluid is selectively and controllably added to the blood, as required for the selected treatment. A secondary fluid is controllably and selectively introduced into the secondary chamber of the filtration unit for controllably collecting material passing across the semipermeable membrane from the blood or for supplying material to pass across the semipermeable membrane into the blood as required for the selected treatment. Materials are removed from the secondary chamber and collected in accordance with the selected treatment.

Abstract: An artificial kidney includes measurement structure for measuring at least one physical characteristic of a fresh dialysis liquid and of used liquid. The measurement structure are disposed in a line portion common to a branch circuit to the feeder line of fresh dialysis liquid and to a branch circuit to the discharge line for the used liquid. Occluding structure permit the liquid to circulate exclusively in one or the other branch circuit. Due to this arrangement, it is possible to obtain the value of the physical characteristics of a patient's blood by calculation as frequently as desired, and to adjust the operation of the kidney permanently to a therapeutic objective set by the physician.

Abstract: An artificial kidney dosing method includes the steps of connecting a patient to an exchanger having first and second compartments separated by a semipermeable membrane. The first compartment is connected to a circuit for extracorporeal blood circulation, and the second compartment has an outlet for draining a waste liquid. After the patient is connected to the exchanger, a perfusion liquid containing a substance (A) is perfused to the patient. The concentration of substance (A) in the blood of the patient is adjusted to a desired concentration {A}.sub.DES, by controlling a flow rate (Q.sub.A) of the perfusion liquid as a function of (1) a flow rate (Q.sub.OUT) of the waste liquid; (2) the desired concentration {A}.sub.DES ; and (3) a concentration {A}.sub.SOL of substance (A) in the perfusion liquid, whereby during this adjustment, a transfer of substance {A} through the semipermeable membrane is taken into account.

Abstract: An apparatus and a method are provided for collecting samples of used dialysate during hemodialysis treatments. A fluid sample is branched off from the main flow of used dialysate into a sample receiving container. The branching off of the sample flow, i.e. withdrawal of the fluid sample, is either time- or volume-controlled so that during the course of a dialysis treatment a predetermined number of fluid samples are withdrawn, whereby the total sample volume has a prescribed ratio relative to the total volume of used dialysate. The recirculation and sample withdrawal conduit is selectively attachable to the sample receiving container for sample collection, or to the inlet of the hemodialysis device to form a recirculation loop for a disinfection cycle. A disinfectant cartridge can be interposed between the recirculation conduit and the hemodialysis device inlet.

Abstract: Methods and apparatus for increasing the accuracy of ultrafiltration in a dialysis machine and decreasing the time required for dialysis. The machine inclused a substantially non-compliant tank for mixing and storing a batch of dialsyate. In a preferred form, the tank is a hollow vessel made from a lightweight and chemically inert material, such as polypropylene, reinforced on its exterior. The machine further includes an ultrafiltration pump for pumping fluid from an extracorporeal circuit to an ultrafiltration tank commensurate with the removal of water from the patient. The pump is calibrated with the volume of fluid in the tank.