Abstract: | Damage of red blood cells (hemolysis) in miniaturized pump systems for heart support is induced by contact with artificial surfaces and high mechanical shear forces. In vitro experiments with porcine blood under well defined material and flow conditions with a new Couette model showed hemolysis not starting until shear stresses of 400 Pa and exposure times of 400 ms. Hemolysis in general was much lower than predicted in earlier investigations. Heparinized blood revealed a more sensitive behaviour as compared to citrated blood (CPDA‐1). |