Patent ID: 8226591

Claim:
A system for controlling extracorporeal blood flow in a patient, the system comprising: a blood pump comprising a rotor, a plurality of rollers carried by the rotor, and a pump chamber extended in tension about the rollers; a sensor configured to measure an operating parameter of the blood pump; a controller coupled to the sensor, the controller calculating flow efficiency of the blood pump based on the operating parameter measured by the sensor and according to the equation FLOW EFFICIENCY=((( Q ÷RPM)×(1+ROLLERS))÷ SV max )×100 wherein: SV max =the maximum stroke volume under maximum filling pressure; Q=output flow rate in volume per minute; RPM=the rotor speed in revolutions per minute; and ROLLERS=the number of rollers on the rotor; and a display device coupled to the controller, the controller being configured to display on the display device the flow efficiency as determined by the controller.