Evaluation of Hemolysis in a Pulsatile Assist Device for Centrifugal Pump

Abstract: To evaluate the blood trauma caused by a new device for producing a pulsatile flow of the centrifugal pump, the pulsatile assist device for the centrifugal pump (PAD-CP) that we have developed, a hemolysis study was performed in vitro and in animal experimentation. For the in vitro testing, 2 identical sets of hemolysis test circuits were prepared with 2,400 ml of bovine blood. The 2 circuits were pumped simultaneously. Plasma total hemoglobin levels were less than 40 mg/dl after 3 h, under a pump flow of 2 L/min. Hemolysis increased to a severe level after 4 h of 4 L/min pump flow. The cause of this hemolysis was thought to be a vibration of the circuit because of incomplete compression of the polyurethane tube in the PADCP. Five adult sheep (average body weight, 47 kg) were used for in vivo evaluation of hemolysis. Hemolysis was less than 30 mg/dl of plasma hemoglobin after 4 h of open chest extracorporeal circulation with 3.0–3.6 Limin of flow rate using the PAD-CP. Other hematologic changes after PAD-CP driving were within normal limits. We conclude that the PAD-CP has proven to have possible clinical applications.