Analysis of the Relation between Blood Flow and Thrombus Formation Using Flow Visualization of Red Blood Cell

Abstract

The present paper deals with relation between a hydrodynamic effect of blood flow and the blood coagulation on artificial organs. In former works, it is considered that the blood coaguration on artificial organs is caused by a biochemical interaction (biocompatibility) and ACT (Activated Coagulation Time) control during extracorporeal circulation. However, the blood coagulation is also under the influence of hydrodynamic effect of blood flows inside of the artificial organs. Therefore quantitative analyses of the flow behavior inside of an artificial organ needs to develop artificial organs, especially for long term use (for example: membrane lung for ECMO). We measured blood flow rate using a velocity vector measurement system (RIX-04) to visualize red blood cell about 1.5-3mm on TV monitor (14 inch) magnified 400 times by CCD microscope. The method of the determination of velocity vector is a two-dimensional correlation technique of binary video data. The three ex-vivo tests were conducted. In experiments, we use flow visuarization models made of artificial materials. The results are as follows: 1. There is a relation between blood flow rate and aggregation of red blood cells. 2. There is a relation between Ht. and rate of blood cell movement. The moving rate of red blood cells (absolute value) after the pump stop are 1.49±0.098, 1.26±0.031, 1.18±0.061 and 0.803±0.19mm/min at Ht. 36, 26, 23 and 17%. These data have significant difference (1%). 3. There is a relation between aggregation section and blood clotting section. 4. We could analyze blood flow inside of the flow visualization models using the velocity vector measurement system. In conclusion, we could consider high Ht. and low blood flow rate at the stagnation point inside of artificial organs formed thrombus easily.