Patent ID: 6759007
Filing Date: 2004-07-06
Classification: A61M,F04B,Y10S

Abstract:
A blood processing system comprisinga separation device that operates to separate blood subject to a positive processing pressure, a fluid pressure actuated blood pump comprising a pump chamber responsive to an applied negative pump pressure to draw blood into the pump chamber and an applied positive pump pressure to expel blood from the pump chamber, a fluid pressure actuated inlet valve governing communicating between the pump chamber and a source of blood responsive to an applied positive valve pressure to close the inlet valve and an applied negative valve pressure to open the inlet valve, a fluid pressure actuated outlet valve governing communicating between the pump chamber and the separation device comprising a valve chamber responsive to an applied positive valve pressure to close the outlet valve and an applied negative valve pressure to open the outlet valve, and an actuator operating to selectively apply positive and negative fluid pressure conditions to the blood pump, inlet valve, and outlet valve; the actuator applying a first negative valve pressure to the inlet valve at a first absolute magnitude; the actuator applying a second negative pump pressure to the blood pump at a second absolute magnitude; the actuator applying a first positive valve pressure to the outlet valve at a third absolute magnitude; said first absolute magnitude greater than said second absolute magnitude; said third absolute magnitude greater than the absolute magnitude of the positive processing pressure.