The invention relates to a dialysis device comprising a device for determining at least one first and second haemodialysis parameter, and a method for determining at least one first and second haemodialysis parameter during a dialysis treatment with a dialysis device. The device 20 for determining at least one first and second haemodialysis parameter comprises a device 21 for generating a change in a physical or chemical parameter of the dialysis fluid in the dialysis fluid system 6 in the form of a bolus, and a device 22 for detecting a change over time in the physical or chemical parameter of the dialysis fluid in the dialysis fluid system 6. Furthermore, the dialysis device has a computing and evaluating unit 23 that is configured such that, on the basis of the change in the physical or chemical parameter in the form of a bolus, for at least one dialysis condition at least one value for the clearance of the dialysis treatment is determined, and, on the basis of at least one value for the clearance, a first and second haemodialysis parameter is determined. The dialysis device according to the invention and the method according to the invention are characterised in that boluses of different sizes, in particular boluses having different area contents, are administered to determine the haemodialysis parameter.

The invention relates to a dialysis machine having an extracorporeal blood circuit, a blood pump, a dialyzer, a venous pressure sensor, a substituate line, and a control unit, wherein the control unit is configured to operate the blood pump in a first operating mode and in a special operating mode and to start the special operating mode after recognition of a trigger event, in which special operating mode a conveying rate of the blood pump is controlled by means of a default value or is regulated to a desired value, which default or desired value is derived from a value determined before the start of the currently started special operating mode or corresponds to said value, wherein the presence of at least one obstacle is polled before the start of the special operating mode, and wherein, on the presence of the obstacle, the start of the special operating mode is blocked or delayed and/or the selection of the default value or of the desire value on the presence of the obstacle differs from the selection without the presence of the obstacle.

The invention relates to a method and to a device for determining an optimum dialysate flow Q.sub.dopt for an extracorporeal blood treatment and to a blood treatment device comprising a device 18 for determining an optimum dialysate flow Qd.sub.opt. The optimum dialysate flow Qd.sub.opt is determined on the basis of a relationship describing the dependence of the clearance K on the dialysate flow Q.sub.d. The device according to the invention comprises a measurement device 18B for measuring at least one value which is characteristic of the clearance K, a calculation and/or evaluation unit 18A of the device according to the invention being configured in such a way that the clearance K is determined on the basis of the at least one value which is characteristic of the clearance. The calculation and/or evaluation unit 18A is configured in such a way that the optimum dialysate flow Q.sub.dopt is determined from the relationship describing the dependence of the clearance K on the dialysate rate Q.sub.d on the basis of the measured clearance K, or the optimum dialysate flow Q.sub.dopt is determined from the measured clearance K.

An apparatus for extracorporeal treatment of blood (1) comprising a treatment unit, a blood withdrawal line, a blood return line, a preparation line and a spent dialysate line. A control unit (10) is configured to calculate values of a parameter relating to treatment effectiveness based on measures of the conductivity in the spent dialysate line. An upstream variation of the value of the characteristic (Cd.sub.in) is caused in the fresh treatment liquid with respect to a prescription baseline (Cd.sub.set) thereby causing a corresponding and timely delayed downstream variation of the same characteristic (Cd.sub.out) in the spent liquid flowing in the spent dialysate line (13). An amplitude (ΔC.sub.in) and/or a duration over time (ΔT) of the upstream variation are/is computed as a function of the flow rate (Qdial) of the fresh treatment liquid in a preparation line (19) or of the parameter correlated to the flow rate (Qdial).

A method that regulates supply of substituate in an extracorporeal blood treatment with an extracorporeal blood treatment apparatus comprising a dialyzer divided by a semipermeable membrane into a blood chamber and a dialyzing fluid chamber and a device for supplying substituate. An extracorporeal blood treatment apparatus that includes a device for regulating supply of substituate. Regulation of supply of substituate in the extracorporeal blood treatment takes place as a function of the rheological loading of the dialyzer. To regulate supply of substituate during extracorporeal blood treatment, rheological loading of the dialyzer is determined from transmembrane pressure on the dialyzer and flow resistance of the dialyzer and substituate rate is increased or reduced according to the loading. The selection of dialyzer parameters or blood parameters is therefore no longer necessary and the distinction between pre-dilution and post-dilution is also made obsolete.

The present invention relates to a method for regulating supply of substituate in an extracorporeal blood treatment with an extracorporeal blood treatment apparatus comprising a dialyzer divided by a semipermeable membrane into a blood chamber and a dialyzing fluid chamber and a device for supplying substituate. Moreover, the present invention relates to an extracorporeal blood treatment apparatus having a device for regulating supply of substituate. Regulation of supply of substituate in the extracorporeal blood treatment takes place as a function of the rheological loading of the dialyzer. To regulate supply of substituate during extracorporeal blood treatment, rheological loading of the dialyzer is determined from transmembrane pressure on the dialyzer and flow resistance of the dialyzer and substituate rate is increased or reduced according to the loading. The selection of dialyzer parameters or blood parameters is therefore no longer necessary and the distinction between pre-dilution and post-dilution is also made obsolete.

An extracorporeal blood treatment apparatus is provided comprising a filtration unit (2) connected to a blood circuit (17) and to a dialysate circuit (32); a control unit (12) is configured for calculating a sodium concentration value for the blood; the estimation of the sodium concentration includes the sub-step of calculating the sodium concentration value as an algebraic sum of a main contribution term based on the isoconductive sodium concentrate and of an offset contribution term based on a concentration of at least a substance in the dialysis fluid chosen in the group including bicarbonate, potassium, acetate, lactate, citrate, magnesium, calcium, sulphate and phosphate.

An extracorporeal blood treatment apparatus is provided comprising a filtration unit (2) connected to a blood circuit (17) and to a dialysate circuit (32), a preparation device (9) for preparing and regulating the composition of the dialysis fluid; a control unit (12) is configured for setting a sodium concentration value for the dialysis fluid in the dialysis supply line (8) at a set point; the setting of the sodium concentration includes the sub-step of calculating the sodium concentration value as an algebraic sum of a main contribution term based on the blood plasma conductivity and of an adjustment contribution term based on a concentration of at least a substance in the dialysis fluid chosen in the group including bicarbonate, potassium, acetate, lactate, citrate, magnesium, calcium, sulphate, and phosphate.

An extracorporeal blood treatment device with a function-monitoring system, wherein the extracorporeal blood treatment device for connection to the vascular system of a patient has an input branch and an output branch. The extracorporeal blood treatment device is equipped, in a first circuit, with at least one first pump arranged between the input branch and output branch for moving the patient's blood, and, in a second circuit filled with liquid and thermally connected to the first circuit of the extracorporeal blood treatment device via a heat exchanger, it has temperature-influencing means. The function-monitoring system has, in the second circuit, two temperature sensors which are arranged upstream (TS2.sub.auf) and downstream (TS2.sub.ab), respectively, with respect to the heat exchanger, in addition, temperature sensor TS1.sub.ab is arranged in the output branch of the first circuit, downstream from the heat exchanger. The function-monitoring system moreover comprises a computer system which is operatively connected to the aforementioned temperature sensors and the temperature-influencing means and which, after the temperature has been influenced, establishes, from the detected temperature values, corresponding thermodilution curves (TDK1.sub.ab, TDK2.sub.ab, TDK2.sub.auf) and, in order to determine an indicator of the function of the extracorporeal blood treatment device, relates the TDK2.sub.ab and the TDK.sub.1ab to each other.

The invention relates to a system for determining a cardiovascular parameter in a patient, wherein the system is adapted to work in conjunction with an extracorporeal blood treatment device (ECBTD) connectable to a patient's vascular system, wherein the ECBTD comprises a first circuit, the system comprising: a liquid-filled, second circuit thermally connected to the first circuit of the ECBTD via a heat exchanger, temperature changing means for generating a temperature change in the second circuit, temperature sensors TS2up and TS2down arranged in the second circuit upstream and downstream of the heat exchanger, respectively. A computer system connected to the temperature sensors and the temperature changing means is adapted to induce a temperature bolus within the first circuit of the ECBTD via the temperature changing means. From the individual temperature recorded as a function of time, temperature curves T2up(t) and T2down(t) are derived and evaluated.