Patent ID: 7981280

Claim:
An extracorporeal blood treatment apparatus comprising: a blood treatment unit; a treatment fluid circuit including a treatment fluid pump operative to circulate treatment fluid around the treatment fluid circuit and through the blood treatment unit; a blood circuit including a blood pump operative to circulate blood around the blood circuit and through the blood treatment unit, an arterial line for withdrawing blood from a patient, and a venous line for returning the treated blood to the patient, the blood pump comprising two chambers and the arterial and venous lines being configured to be switched between a first condition in which they are connected to the patient and a second condition in which they are disconnected from the patient and connected to each other for recirculation of blood through the blood circuit; and a controller configured to operate the pumps in a treatment mode during which both the blood pump and the treatment fluid pump are operated to circulate blood and treatment fluid through the blood treatment unit while the arterial and venous lines are in the first condition, and in a recirculation mode during which the treatment fluid pump is inactivated and the blood pump is operated to circulate the blood through the blood circuit while the arterial and venous lines are in the second condition.