National Institute of Advanced Industrial Science and Technology, Institute for Human Science and Biomedical Engineering, Tsukuba, Ibaraki, Japan.
Artif Organs. 2009 Oct;33(10):798-804. doi: 10.1111/j.1525-1594.2009.00817.x. Epub 2009 Jul 22.
We have developed a noncontact-type centrifugal blood pump with hydrodynamic bearings and a semi-open impeller for mechanical circulatory assist. The impeller is levitated by an original spiral-groove thrust bearing and a herringbone-groove journal bearing, without any additional displacement-sensing module or additional complex control circuits. The pump was improved by optimizing the groove direction of the spiral-groove thrust bearing and the pull-up magnetic force between the rotor magnet and the stator coil against the impeller. To evaluate hemocompatibility, we conducted a levitation performance test and in vitro hemocompatibility tests by means of a mock-up circulation loop. In the hemolysis test, the normalized index of hemolysis was reduced from 0.721 to 0.0335 g/100 L corresponding to an expansion of the bearing gap from 1.1 to 56.1 microm. In the in vitro antithrombogenic test, blood pumps with a wide thrust bearing gap were effective in preventing thrombus formation. Through in vitro evaluation tests, we confirmed that hemocompatibility was improved by balancing the hydrodynamic fluid dynamics and magnetic forces.
我们开发了一种具有液力轴承和半开式叶轮的非接触式离心血泵，用于机械循环辅助。叶轮通过原始的螺旋槽推力轴承和人字形槽径向轴承悬浮，无需任何额外的位移传感模块或额外的复杂控制电路。通过优化螺旋槽推力轴承的槽方向和转子磁铁与定子线圈对叶轮的提升磁力，对泵进行了改进。为了评估血液相容性，我们通过模拟循环回路进行了悬浮性能测试和体外血液相容性测试。在溶血试验中，溶血的归一化指数从 0.721 降低到 0.0335 g/100 L，这对应于轴承间隙从 1.1 扩展到 56.1 微米。在体外抗血栓形成试验中，具有宽推力轴承间隙的血泵可有效防止血栓形成。通过体外评估测试，我们证实通过平衡流体动力学和磁力可以提高血液相容性。
