Antithrombogenicity evaluation of a centrifugal blood pump

The Gyro C1E3 pump was developed not only for cardiopulmonary bypass but al so as a short-term assist device. The main purpose of this study was to exa mine the correlation between the thrombus formation factor and the Gyro C1E 3 pumps. Seven pumps were implanted into 3 calves and evaluated for differe nt periods of duration as a paracorporeal left ventricular assist device (L VAD). One pump was subjected to percutaneous cardiopulmonary support condit ion (PCPS) (total pressure head 500 mm Hg with a pump flow rate of 3 L/min) . The anticoagulation treatment consisted of a continuous administration of heparin to maintain an activated clotting time (ACT) of 200-250 during the LVAD study and 250-300 during the PCPS study. After the experiment, the pu mps were disassembled and examined. In cases where there were any blood-der ived deposits inside the pumps, the dry weight of these thrombi that adhere d to the bearing area of the pump was measured. A multiple correlation was attempted to speculate possible thrombus formation. The estimated dry weigh t of thrombi was calculated from pump flow rate, pumping day, motor speed, and activated clotting time. This equation was estimated dry weight of thro mbi = 1.140 x pump flow rate -0.001 motor speed + 1.652 pumping time -0.041 x ACT + 2.198 R-2 = 0.944. This study suggested that there was a possibili ty to calculate the amount of adhered thrombus formation from pump flow rat e, motor speed, pumping day, and ACT.