The present invention relates to a flow sensor for measuring a flow difference having at least two measurement chambers through which fluid is conductible; at least one means for producing a magnetic field for charge separation in a fluid flowing through the at least two measurement chambers; and at least one means for measuring an electric potential in the fluid flowing through the at least two measurement chambers, with the at least two measurement chambers being arranged such that they are run through by the same magnetic field line of the magnetic field for charge separation.

Method and device according to the method for determining intracellular and/or extracellular, in particular macromolecular fractions of fluids, preferably of body fluids of living organisms, with the steps: coupling-in a measurement signal through an electrically non-conductive wall into the fluid to be measured; coupling-out an electrical measurement value that is thereby generated in the fluid to be measured; detecting the coupled-out electrical measurement value at a plurality of different frequencies of the electrical measurement signal; determining the intracellular and/or extracellular, in particular macromolecular fractions of the fluid to be measured by means of evaluation of the detected electrical measurement value at a plurality of frequencies of the measurement signal.

A sensor/transducer for use in reducing leakage current from a patient fluidly connected to a medical device by tubing filled with a conductive fluid (e.g., blood or dialysate (a “fluid line”)) includes a magnetically conductive core with 1) a centrally located support for a coil of fluid line, and 2) coiled electrical conductors located at positions that are spaced from the centrally located support, on opposite sides of the centrally located support. The sensor/transducer can be used to measure leakage current carried by the conductive fluid in the fluid line, or it can be used to induce current in the fluid line in a manner that reduces the leakage current.

A blood purification apparatus that detects dislodgement of a puncture needle is provided. The apparatus includes an arterial electrode, a venous electrode, a power source capable of causing a current to flow through an arterial puncture needle and a venous puncture needle that are stuck in a patient, a body-surface electrode closely attached to a body surface of the patient, a detection device capable of acquiring a heart rate of the patient in accordance with an electrical signal detected by the body-surface electrode, a monitoring device capable of monitoring in real time the current flowing through the arterial electrode or the venous electrode and a change in an impedance in a body of the patient that is detected by the detection device, and an identifying device capable of identifying a dislodged state where the arterial puncture needle or the venous puncture needle is dislodged from the patient, in accordance with the change in the impedance that is an object of monitoring by the monitoring device.

A blood purification apparatus is provided that is capable of detecting an abnormal state of puncture into a blood vessel with an arterial puncture needle or a venous puncture needle. The blood purification apparatus includes an oscillating device capable of supplying an alternating current at a predetermined frequency and changing the frequency of the alternating current among a plurality of frequencies, a measuring device capable of measuring an impedance for each of the frequencies, a calculating device capable of acquiring an impedance frequency characteristic, a storage device capable of storing an impedance frequency characteristic acquired in a case of normal puncture into the patient's blood vessel with an arterial puncture needle and a venous puncture needle, and an identifying device capable of identifying whether the puncture into the blood vessel with the arterial puncture needle a or the venous puncture needle b is normal in accordance with the change observed between the impedance frequency characteristic acquired by the calculating device and the impedance frequency characteristic stored in the storage device.

An object is to provide a blood purifying device and an access flow rate measuring method enabling easy and accurate measurement of an access flow rate of an access vessel. A blood purifying device includes a flow rate calculating unit calculating the access flow rate of an access vessel based on an initial blood indicator for blood distributed through a vein side circuit and flowing through the access vessel of a patient, the flow rate distributed through measuring means when a pump is reversed to cause the priming solution to flow out from an artery side circuit, and a blood indicator for the blood diluted with the priming solution which is obtained when the pump is reversed to dilute, with the priming solution, the blood distributed through the vein side circuit.

A dialysis machine (e.g., a peritoneal dialysis machine) may include a housing. The machine may further include a leak detector disposed in the housing, the leak detector being an electrical circuit. In response to fluid contacting the leak detector, a leak in the dialysis machine is detectable. The machine is configured to send a signal based on a short of the electrical circuit from fluid contact with the leak detector to indicate a leak condition.

A dialysis machine (e.g., a peritoneal dialysis machine) may include a housing. The machine may further include a leak detector disposed in the housing, the leak detector being an electrical circuit. In response to fluid contacting the leak detector, a leak in the dialysis machine is detectable. The machine is configured to send a signal based on a short of the electrical circuit from fluid contact with the leak detector to indicate a leak condition.

A sensor/transducer for use in reducing leakage current from a patient fluidly connected to a medical device by tubing filled with a conductive fluid (e.g., blood or dialysate (a fluid line)) includes a magnetically conductive core with 1) a centrally located support for a coil of fluid line, and 2) coiled electrical conductors located at positions that are spaced from the centrally located support, on opposite sides of the centrally located support. The sensor/transducer can be used to measure leakage current carried by the conductive fluid in the fluid line, or it can be used to induce current in the fluid line in a manner that reduces the leakage current.

An apparatus for extracorporeal treatment of blood (1) comprising a treatment unit (2), a blood withdrawal line (6), a blood return line (7), a preparation line (19) and a spent dialysate line (13); a non-invasive blood volume sensor (50) for determining an additional property of blood is active on a tube segment (61) of the blood withdrawal line or of the blood return line; the sensor includes one source (53) for directing a signal towards the blood, a plurality of detectors (57) for receiving the signal, and a controller (65) receiving the output signals from the detectors (57) and determining a blood volume variation and a value of sodium concentration in the blood (Na.sub.pl) both based on the output signals. A process of determining at least one parameter and on property of blood circulating an extracorporeal blood circuit is also disclosed.