Qian K X
Shanghai Second Medical University, Peoples Republic of China.
J Biomed Eng. 1990 Nov;12(6):533-5. doi: 10.1016/0141-5425(90)90066-v.
In the experimental and clinical support of the failing heart, the impeller-type centrifugal pumps continue to be of interest because of their inherent advantages; however, the blood compatibility of these pumps still remains to be improved. From the viewpoint of haemodynamics, thrombosis and haemolysis could be reduced by eliminating the stagnation and turbulence of blood flow within the pump, which frequently takes place near the blood contracting surfaces of the pump, when the impeller contours do not coincide with the stream surfaces of the blood. It is suggested that it could be advantageous to design impeller contours according to the stream surfaces, by solving the partial differential equations of continuity, motion and energy. An impeller shroud and vane based on this approach would be fully rinsed by non-turbulent flow and there would then be neither stagnation nor turbulence within the pump, with the result that thrombosis and haemolysis could be reduced. A new impeller pump, developed according to this method, was evaluated as a left ventricular device in four dogs. The bypass flow was controlled at 40-50% of the total flow, each test lasting 6 h. All of the haematological parameters, measured every 2 h, remained within normal range. There was no thrombosis, and coagulation in the pump was avoided by a small dose of heparin to maintain the activated coagulation time (ACT) under 200" in the experiments.
在对衰竭心脏的实验和临床支持中，叶轮式离心泵因其固有优势一直备受关注；然而，这些泵的血液相容性仍有待提高。从血液动力学的角度来看，当叶轮轮廓与血液的流线表面不一致时，泵内血液收缩表面附近经常会出现血液流动的停滞和湍流，通过消除这种情况可以减少血栓形成和溶血。有人提出，通过求解连续性、运动和能量的偏微分方程，根据流线表面设计叶轮轮廓可能是有利的。基于这种方法的叶轮护罩和叶片将被非湍流完全冲洗，泵内既不会有停滞也不会有湍流，从而可以减少血栓形成和溶血。根据这种方法开发的一种新型叶轮泵，在四只狗身上作为左心室装置进行了评估。旁路流量控制在总流量的40 - 50%，每次测试持续6小时。每2小时测量的所有血液学参数均保持在正常范围内。没有血栓形成，并且在实验中通过小剂量肝素避免了泵内凝血，以将活化凝血时间（ACT）维持在200秒以下。
