Patent ID: 8721879

Claim:
A hemodialysis system, comprising: a blood flow path through which untreated blood is drawn from a patient and passed through a dialyzer; a dialysate flow path through which dialysate flows from a dialysate supply through the dialyzer, the dialysate flow path and the blood flow path being in fluidic communication; a reciprocating positive displacement blood pump configured to pump blood in the blood flow path, resulting in blood flow through the dialyzer; a reciprocating positive displacement dialysate pump configured to pump dialysate in the dialysate flow path, resulting in dialysate flow through the dialyzer; and a controller configured to receive pressure information associated with the blood flow path and/or pressure information associated with the dialysate flow path, and configured to control the dialysate pump and/or the blood pump; wherein the controller uses the pressure information during dialysis to control the dialysate pump and/or the blood pump such that the pressure of the dialysate exiting the dialyzer is lower than the pressure of the blood exiting the dialyzer.