动脉内叶轮泵结构简化对流体力学特性的影响

Impact of Impeller Simplification on Hydrodynamic Feature of Intra-Aortic Impeller Blood Pump

目的:改进先前的"动脉内叶轮泵"心脏辅助装置。方法:先前的"动脉内叶轮泵"叶轮连接于一个圆柱形的永磁转子。改进后的"动脉内叶轮泵"永磁体转子直接包埋在叶轮的轮毂内,可在简化泵结构的条件下获得相近的流体输出,并减小泵的被动阻力。叶轮外径17.8 mm,支架筒内径为18 mm,相应的刚性支架外径22 mm,长40 mm。泵总质量约12 g。结果:改进后"动脉内叶轮泵"结构简化,体外模拟测试表明在转速9 900 r/min和100 mmHg(1 mmHg=133.322 Pa)后负荷条件下输出流量为5 L/min;三叶片叶轮的流体输出特性较好。结论:改进后的"动脉内叶轮泵"结构简单化,但仍然具有较好的流体力学特性,可用于左心辅助,此结果可为进一步优化泵设计提供实验基础。

Objective To improve ventricular assistant device.Methods In the previous structure of Intra-Aortic Impeller,the impeller was connected to a column magnetic rotor.In this reformative structure,the magnetic rotor was embedded inside the impeller hub directly.This modification resulted in a simply pump structure and reduction of the pump＇s resistance to the flow stream while without markedly impairing its function.The impellers of newly fabricated Intra-Aortic Impeller pump were 17.8 mm in diameter,and the rigid cage was 18 mm in inside diameter and 22 mm in out diameter with 40 mm of length,totally weighing 12 gram.It was evaluated in a mock circulation to study the hydrodynamic characteristics.Results The vitro study showed that the hydrodynamic featured of the intra-aortic impeller was strongly infected by its impeller configuration.The newly fabricated intra-aortic impeller pump could produce output of 5L/min against the pressure of 100 mmHg at a rotational speed of 9900 RPM,which was enough for left ventricular assistance.The hydrodynamic output was slightly increased with the impeller of three blades.Conclusion The newly fabricated intra-aortic impeller pump has excellent characteristics.The pump hydrodynamic efficiency is eligible for a VAD while possess the advantages of simple structure and facility for fabricating.