Nonlinear Flow Rate Response to Pumping Frequency and Reduced Hemolysis in the Drastically Under-Occluded Pulsatile Roller Pump.

Roller pumps are widely used in many medical procedures including cardiopulmonary bypass, left/right ventricular assist, and hemodialysis. However, to date, the problem of the roller pumping mechanism causing significant hemolysis remains unresolved. It has been shown that with under-occlusion of the roller pump, hemolysis can be reduced, but significant reduction of the mean flow rate also takes place due to backflow through the under-occlusion.