動圧浮上遠心血液ポンプの軸受隙間内ヘマトクリット算出法の有効性評価

抄録

Understanding erythrocyte behavior, especially changes in hematocrit in narrow gaps of mechanical circulatory support devices, is important to decrease the pump-derived hemolysis. The present study aimed to propose and evaluate a method of calculating hematocrit in narrow gaps using a high-speed microscope and a laser confocal displacement meter. We calculated hematocrit based on scatter theory and erythrocyte occupancy, mean corpuscular volume, clearance gap, and modeled cross-sectional areas of erythrocytes. The method was initially validated using bovine blood with hematocrit ≤ 1.0% and a comparison of the cross-sectional area modeling. Hematocrit in a spiral groove bearing of a blood pump was then evaluated using bovine blood with hematocrit of 1.0%. As the result, hematocrit calculated using this method was essentially equal to that of the test blood when the circulatory cross-sectional area modeling of biconcave erythrocyte was used. We confirmed that the new method could calculate hematocrit ≤ 1.0% in gaps ≤ 50 μm wide.