2000 Fiscal Year Final Research Report Summary
Study on the Effect of Pulsatile Flow on Thrombus Formation and Red Blood Cell Destruction
| Project/Area Number |
11680854
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Biomedical engineering/Biological material science
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| Research Institution | Osaka Institute of Technology |
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Principal Investigator |
HASHIMOTO Shigehiro Faculty of Eng, Osaka Institute of Technology Associate Professor, 工学部, 助教授 (00146515)
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| Project Period (FY) |
1999 – 2000
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| Keywords | Biomedical Measurement / Artificial Organs / Thrombus Formation / Red Blood Cell Destruction / Pulsatile Flow |
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| Research Abstract |
Periodically fluctuating shear rates are applied to the blood in pulsatile flow powered by pulsatile pumps. The hydrodynamic effects of periodically fluctuating shear rate on clot growth and on erythrocyte destruction have been investigated in vitro to study quantitatively thrombus formation and hemolysis in pulsatile flow.
Sinusoidally fluctuated uniform shear rates in the Couette flow were applied to the blood which filled the space in the concave-convex cones or in the parallel-discs-type of rheosope systems. Both systems were made from transparent polymethyl-methacrylate to enable the blood sample to be observed. Evaluation of clot growth was derived from the clot ratio, which was experimentally determined from the rate of increase of apparent viscosity in the blood. Evaluation of erythrocyte destruction was derived from the hemolysis ratio, which was calculated from plasma hemoglobin count per whole blood hemoglobin count.
The results show that clot growth is controlled so as not to occupy a large space when the time of application of lower (<100 s-1) shear rates are modified by the wash-out effect of intermittent application of higher (>500 s-1) shear rates, and that erythrocyte destruction including sub-lethal damage decreases when the exposure time of larger (>500 s-1) shear rates are interspersed with smaller (<300 s-1) shear rates.
This study demonstrates that pulsatile flow plays an important role in controlling thrombus formation and hemolysis. The results of this study are applied to the design and the control of rotary blood pumps.
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Research Products
(10 results)
