Wakisaka Y, Taenaka Y, Araki K, Chikanari K, Nakatani T, Baba Y, Anai H, Eya K, Toda K, Takano H
Department of Artificial Organs, National Cardiovascular Center Research Institute, Osaka, Japan.
Artif Organs. 1997 Feb;21(2):148-53. doi: 10.1111/j.1525-1594.1997.tb00352.x.
Antithrombogenicity in an initial type (N1) of a centrifugal pump (CP) developed in our institute is provided by the central balancing hole of an impeller. A new CP (N2) was modified to obtain better antithrombogenicity, in which the balancing hole was widened to improve self washout flow velocity (Vsf), and an edge of the thrust bearing was rounded off to minimize flow separation. Effects of the modifications were assessed in vitro and in vivo studies. The Vsf of the N1 and the N2 evaluated by a Doppler velocimeter were 12.8 and 22.1 cm/s, respectively. Flow around the thrust bearing, which was visualized by a light cutting method, confirmed less flow stagnation in the N2. The hemolytic indices of the N1 and the N2 were 0.023 and 0.008 mg/dl, respectively. In vivo antithrombogenicity and the hemolytic properties of the N2 and the N1 were investigated without anticoagulation therapy in 3 goats. In each goat the N2 was driven for 1 week and exchanged for the N1, which was driven for the same period. Red thrombi at the thrust bearing were found in 2 N1s, and 2 small thrombi were on the impeller of another N1, whereas a thrombus of less than 1 mm3 at the TB was noted in 1 N2. Plasma free hemoglobin was not increased in either CP. These results indicate that the N2 has better antithrombogenicity and hemolytic properties than the N1.
我们研究所研发的离心式泵（CP）初始型号（N1）的抗血栓形成性由叶轮的中心平衡孔提供。一种新的CP（N2）经过改进以获得更好的抗血栓形成性，其中平衡孔被扩大以提高自冲洗流速（Vsf），并且推力轴承的边缘被倒圆以最小化流动分离。通过体外和体内研究评估了这些改进的效果。用多普勒测速仪评估的N1和N2的Vsf分别为12.8和22.1厘米/秒。通过光切割法可视化的推力轴承周围的流动证实N2中的流动停滞较少。N1和N2的溶血指数分别为0.023和0.008毫克/分升。在3只山羊中，在没有抗凝治疗的情况下研究了N2和N1的体内抗血栓形成性和溶血特性。在每只山羊中，N2驱动1周，然后换成N1，N1也驱动相同的时间。在2个N1的推力轴承处发现红色血栓，在另一个N1的叶轮上发现2个小血栓，而在1个N2的推力轴承处发现一个小于1立方毫米的血栓。两种CP的血浆游离血红蛋白均未增加。这些结果表明，N2比N1具有更好的抗血栓形成性和溶血特性。
