A heat exchanger for a blood circulation circuit includes a hollow fiber membrane layer having a plurality of laminated hollow fiber membranes 31. Each of the hollow fiber membranes 31 has a barrier layer 5 having a hydrogen peroxide barrier property, and the barrier layer 5 has an oxygen permeability coefficient of 6 cc.Math.cm/m.sup.2.Math.24 h/atm or less at 25° C.

A heat exchanger for a blood circulation circuit includes a hollow fiber membrane layer having a plurality of laminated hollow fiber membranes 31. Each of the hollow fiber membranes 31 has a barrier layer 5 having a hydrogen peroxide barrier property, and the barrier layer 5 has an oxygen permeability coefficient of 6 cc.Math.cm/m.sup.2.Math.24 h/atm or less at 25° C.

A cassette integrated system. The cassette integrated system includes a mixing cassette, a balancing cassette, a middle cassette fluidly connected to the mixing cassette and the balancing cassette and at least one pod. The mixing cassette is fluidly connected to the middle cassette by at least one fluid line and the middle cassette is fluidly connected to the balancing cassette by at least one fluid line. The at least one pod is connected to at least two of the cassettes wherein the pod is located in an area between the cassettes.

A cassette integrated system. The cassette integrated system includes a mixing cassette, a balancing cassette, a middle cassette fluidly connected to the mixing cassette and the balancing cassette and at least one pod. The mixing cassette is fluidly connected to the middle cassette by at least one fluid line and the middle cassette is fluidly connected to the balancing cassette by at least one fluid line. The at least one pod is connected to at least two of the cassettes wherein the pod is located in an area between the cassettes.

A holder for a curved duct portion of a tube pump. The holder includes a supply-side connector which includes a first cavity and a first plate connected together, the first cavity being adapted for receiving an end of the curved duct portion, and a discharge-side connector including a second cavity and a second plate connected together, the second cavity being adapted for receiving another end of the curved duct portion, where the connectors are movable the one with respect to the other between a storage configuration, in which the supply-side connector is positioned away to the discharge-side connector, and an operating configuration, in which the supply-side connector is close to the discharge-side connector and in which the first and second plate are engaged together substantially on a same plane.

A holder for a curved duct portion of a tube pump. The holder includes a supply-side connector which includes a first cavity and a first plate connected together, the first cavity being adapted for receiving an end of the curved duct portion, and a discharge-side connector including a second cavity and a second plate connected together, the second cavity being adapted for receiving another end of the curved duct portion, where the connectors are movable the one with respect to the other between a storage configuration, in which the supply-side connector is positioned away to the discharge-side connector, and an operating configuration, in which the supply-side connector is close to the discharge-side connector and in which the first and second plate are engaged together substantially on a same plane.

A portable hemodialysis system is provided including a dialyzer, a closed loop blood flow path which transports blood from a patient to the dialyzer and back to the patient, and a closed loop dialysate flow path which transports dialysate through the dialyzer. In addition, the hemodialysis system includes two reservoirs which can be alternately placed in the dialysis flow path using various controllable fluid valves. The weight, and therefore the level of dialysate, of each reservoir is measured by a preferred level sensor having a strain measuring device which includes a load cell and a tilt sensor. The load cell and tilt sensor are electrically connected to a processor for sending force and tilt measurements to the processor. The processor may analyze the tilt measurements to correct for any inaccurate measurements of the load cell caused by the tilt.

A portable hemodialysis system is provided including a dialyzer, a closed loop blood flow path which transports blood from a patient to the dialyzer and back to the patient, and a closed loop dialysate flow path which transports dialysate through the dialyzer. In addition, the hemodialysis system includes two reservoirs which can be alternately placed in the dialysis flow path using various controllable fluid valves. The weight, and therefore the level of dialysate, of each reservoir is measured by a preferred level sensor having a strain measuring device which includes a load cell and a tilt sensor. The load cell and tilt sensor are electrically connected to a processor for sending force and tilt measurements to the processor. The processor may analyze the tilt measurements to correct for any inaccurate measurements of the load cell caused by the tilt.

An improved valve leak detection system. The improved valve leak detection system comprises a membrane pump defining a flow path arranged to be opened and closed by at least one valve, a measuring device, a comparator, and a signal generator. The measuring device is configured to determine a conductivity value between two points on the flow path of the membrane pump, one point arranged upstream of the at least one valve and the other point arranged downstream of the at least one valve. The measuring device measures the conductivity value when the at least one valve is closed. The comparator is configured to continuously monitor the conductivity value. The signal generator is arranged to provide an output signal when the conductivity value is indicative of a valve leak condition for a set number of measurements within a set period of time.

An improved valve leak detection system. The improved valve leak detection system comprises a membrane pump defining a flow path arranged to be opened and closed by at least one valve, a measuring device, a comparator, and a signal generator. The measuring device is configured to determine a conductivity value between two points on the flow path of the membrane pump, one point arranged upstream of the at least one valve and the other point arranged downstream of the at least one valve. The measuring device measures the conductivity value when the at least one valve is closed. The comparator is configured to continuously monitor the conductivity value. The signal generator is arranged to provide an output signal when the conductivity value is indicative of a valve leak condition for a set number of measurements within a set period of time.