Reevaluation for long-term use of Extracorporeal Membrane Oxygenator

本研究提出了改进我国离心式血泵以适应长期使用ECMO泵，并阐明了ECMO系统在长期使用中存在的问题。我们的ECMO系统由一个微型血泵和一个独特的圆柱形血流膜氧合器组成。我们的泵在其轴承的上部和下部产生血栓的问题，最初的一年，我们用慢性动物检查检查了泵的血液相容性，并通过计算流体动力学分析评估了氧合器中的血液流动模式。我们的血泵在下部轴承处没有血栓形成，但是在上部没有改善。通过CID分析，我们的氧合器在壳体拐角堵塞方面优于商业氧合器。去年，我们制造了3种型号的泵，修改了上轴承周围。经慢性动物实验，各型泵均改善了血液相容性。其中，具有长入口以将血液直接引导到上轴承的泵是最好的兼容性。通过对该氧合器的研究，将其与膜间距相近的圆柱型和方柱型氧合器进行了比较。在气体交换性能方面，圆柱型氧合器比柱状氧合器好10%。而且，我们的儿童氧合器符合AAMI成人氧合器标准。这一结果已通过幼犬急性动物实验得到证实，并与我们的儿童用氧合器和市售成人用氧合器进行了比较，未来我们应完善我们的ECMO系统，使其具有最小的充注量和高质量的血液相容性，并进一步研究ECMO系统长期使用时对器官的损害问题。

In this study, we should improve our centrifugal blood pump for long-term ECMO pump, and clarified the problem in prolonged use of ECMO system. Our ECMO system consisted of a miniature blood pump and a unique membrane oxygenator with cylindrical blood stream. Our pump had problem that was produced thrombus at the upper and lower parts of its bearing.Initial year, we examined blood compatibility of the pump with chronic animal examination, and assess blood flow patterns in the oxygenator by Computational Fluid Dynamics analysis. Our Blood pump was bred no thrombus formation at lower bearing, however, not improved at upper part. Our oxygenator had an advantage over commercial oxygenators in congestion at corners of casing by CID analysis.Final year, we manufactured 3-type models of pump, modifying around upper bearing. By chronic animal exam, all types of pump were improved the blood compatibility. Moreover, the pump with long inlet port for guiding blood flow directly to upper bearing was the best compatibility among them. By investigation of the oxygenator, we compared with cylindrical and square pillar oxygenators, which had similar membrane space. In gas exchange performance, cylindrical oxygenators were better 10% than pillar oxygenators. And, our oxygenator, which was for children, met AAMI standard for of oxygenator for adults. This result was confirmed by acute animal examination with puppy, under comparing with our oxygenator for child and a commercial oxygenator for adult.In the future, we should complete our ECMO system, which had minimum quantity of filling and high quality of blood compatibility, and investigate further problems against organs in long-term use of ECMO system.