Haematological variations in pigs during experimental left ventricular assistance with a pulsatile impeller pump

Left ventricular assistance with a pulsatile impeller pump was performed on 5 pigs. The pump delivered the blood from the left atrium to the aorta. The by-pass flow was adjusted to 40% of the total flow. All of the haematological variations were measured every hour. The results demonstrated that the pulsatile impeller pump caused less erythrocyte but more platelet damage than the nonpulsatile impeller pump in some experiments by dogs. The free haemoglobin was unchanged but lactate dehydrogenase increased remarkably in 6 h. Compared with the same experiments of the pulsatile impeller pump in goats and roller pump in pigs, it seems that the pig erythrocytes have more endurance to shear stress than that of dogs and goats, and pig platelets are more sensitive to mechanical force than those of other animals. The chronic experiment of pulsatile impeller pump is now in the planning stage for further investigations.