Patent ID: 7615028

Claim:
An extracorporeal blood treatment system comprising: a blood circuit comprising a first blood passage coupled to a blood treatment device coupled to a first end of the treatment device and a second blood passage coupled to an opposite end of the treatment device, wherein said first and second blood passages are each adapted to be coupled to a vascular system of a human patient; a reversible first blood pump connectable to the first blood passage and a reversible second blood pump connectable to the second blood passage, wherein said first and second blood pumps are adapted to reverse pumping directions to move blood through the first and second blood passages in a first direction and alternatively in a reverse direction, wherein blood is withdrawn from a patient into the first blood passage and infused into the patient through the second blood passage while the first and second blood pumps turn in a first direction, and blood is withdrawn from the patient into the second blood passage and infused into the patient through the first blood passage while the first and second blood pumps turn in an opposite direction, and a pump controller operatively connected to the first and second blood pumps, said controller operates the blood pumps to reverse the pumping directions to cyclically move blood through the first and second blood passages in the first direction and in the reverse direction a filter having a filtrate output tube and said system further comprises a filtrate pump connectable to the filtrate output tube, wherein the filtrate pump is temporarily stopped while the blood flow though the circuit is reversed.