Studies on a blood pump based on a novel principle (eccentric revolution)

本研究开发了一种新型血泵。泵壳内只有弹性膜。在泵壳和弹性膜之间，含有比重与血液不同的流体或空气。通过偏心旋转泵壳，同时禁止泵壳本身旋转，即可获得泵的流量和压力。该泵结构非常简单，没有任何叶轮、叶片或阀门，这会带来血栓形成和密封泄漏等各种问题，限制了泵的长期使用。这种泵送原理为血泵的长期应用提供了良好的条件。该泵具有以下特点：1)产生的压力和流量与泵壳旋转的平方成正比；2)泵的输出与泵壳的偏心度成正比；3)在本实验系统中，在650转/分的转速下，相对于650 MMH2O的流量为700毫升/分钟。4)弹性膜和泵壳之间存在一个最佳的含气量。当弹性膜突然关闭进气口时，泵的输出最大。5)泵内的流量不是连续的浮体，而是与泵壳旋转同步的脉动流。6)认为该泵兼有离心泵和容积泵的特点。

A new blood pump was developed in this study. It has only elastic membrane inside the pump case. Between the pump case and elastic membrane, fluid or air which, has different specific gravity than blood is contained. By rotating the pump case eccentrically while prohibiting revolution of pump case itself, flow and pressure were obtained from the pump. The pump has very simple structure and does not have any impeller, vanes, or valves, which bring about various problems such as thrombus formation and leakage through seals, which limit prolonged usage of the pump. This pumping principle is promising for blood pump capable of longer term application. The pump has the following characteristics :1)The generated pressure and flow are proportional to the square of the revolution of the pump case.2)Pump output is proportional to the eccentricity of the pump case revolution.3)In the present experimental system, flow rate of 700 mL/min against 650 mmH_2O was obtained at 650 rpm of revolution.4)There is an optimal amount of air or fluid contained in the space between the elastic membrane and pump case. The pump output was maximum when the elastic membrane alightly closed the inlet port. It suggested that the elastic membrane functioned as a kind of a valve in this pump.5)Flow from the pump was not continuous flot4, but pulsatile flow synchronizing the pump case revolution.6)The pump was considered to have both characteristics of centrifugal pump and positive displacement pump.