Hemolytic effect of surface roughness of an impeller in a centrifugal blood pump.
Hemolytic effect of surface roughness of an impeller in a centrifugal blood pump.
复制标题
离心血泵叶轮表面粗糙度的溶血效应。
作者：
Y. Takami;T. Nakazawa;K. Makinouchi;E. Tayama;J. Glueck;R. Benkowski;Y. Nosé
本研究调查如何叶轮的表面粗糙度影响溶血的枢轴轴承支持陀螺仪C1 E3泵。本文针对叶轮式离心泵叶轮表面的特殊区域进行了研究。七个陀螺仪C1 E3泵准备与光滑表面的外壳和不同的叶轮部分具有不同的表面粗糙度。叶轮的叶片、顶面和背面分别进行蒸汽抛光、细喷砂或粗喷砂，以产生三种不同等级的表面粗糙度。然后用表面轮廓仪检查这些表面。使用具有不同叶轮的这些泵，模拟心肺转流（5 L/min，350 mm Hg）进行体外溶血试验。本研究的结果最终证明，叶轮背面的表面粗糙度对溶血的影响最大，其次是顶部，然后是叶片。以下是这些调查结果的原因。首先，由于背面和壳体之间的间隙较小以及相对于叶轮的相对速度较大，背面的剪切速率可能大于顶面。第二，叶轮下方的流体可能具有较长的暴露时间，因为流体在叶轮下方混合的机会很小。第三，叶轮顶侧的剪切速率可能大于叶片上的剪切速率，因为在叶片后面形成涡流。
The present study investigates how the surface roughness of an impeller affects hemolysis in the pivot bearing supported Gyro C1E3 pump. This study focuses on particular areas of the impeller surface in the impeller type centrifugal pump. Seven Gyro C1E3 pumps were prepared with smooth surface housings and different impeller parts with different surface roughnesses. The vanes, top side, and backside of the impeller were independently subjected to vapor polishing, fine sand blasting, or coarse sand blasting to produce three different grades of surface roughness. These surfaces were then examined by a surface profile instrument. Using these pumps with different impellers, in vitro hemolysis tests were performed simulating cardiopulmonary bypass (5 L/min, 350 mm Hg). The findings of this study conclusively proved that surface roughness of the back side of the impeller has the greatest effect on hemolysis, followed by the top side and then the vanes. The following are reasons for these findings. First, the shear rate may be greater on the back side than on the top side because of the smaller gap between the back and the housing and the greater relative speed against the impeller. Second, the fluid beneath the impeller may have a longer exposure time because there is little chance for the fluid to mix beneath the impeller. Third, the shear rate may be greater on the top side of the impeller than on the vanes because a vortex formation occurs behind the vanes.