Blood flow and damage by the roller pumps during cardiopulmonary bypass

Although much CFD work has been carried out to study the blood damage created in a centrifugal pump used for a cardiopulmonary bypass, little is known about the blood flow and consequent damage in a roller pump. A time-dependent moving boundary problem is solved in this paper to explore the blood flow and damage in the roller pump. An initial attempt to predict the blood damage from these simulations is also made and results are compared with experimental observations. It is discovered that reducing the amount of time two rollers simultaneously occlude the tubing, will reduce the blood exposure to shear stress significantly and consequently reduce the blood damage caused.