Patent ID: 7563240

Claim:
A blood treatment device comprising a blood purification element, divided into two chambers by a semipermeable membrane, whose first chamber is part of a dialysis fluid loop and whose second chamber is part of an extracorporeal blood loop, a dialysis fluid supply line for supplying fresh dialysis fluid to the first chamber and/or into the blood loop, a dialysis fluid removal line for removing used dialysis fluid from the first chamber, a control unit for controlling the blood treatment device, at least one sensor on at least one of the blood loop or the dialysis fluid loop, the sensor being configured to detect and measure a concentration of a first material capable of penetrating the semipermeable membrane, and an analysis unit operatively connected to the at least one sensor and configured to determine i) a blood purification performance L 1 of the blood purification element for the first material based on the measurement values of the at least one sensor and ii) a blood purification performance L 2 of the blood purification element for a second material, which is different from the blood purification performance L 1 for the first material, based on data stored in the analysis unit that define a relationship between the blood purification performance L 1 for the first material and the blood purification performance L 2 for the second material.