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INFLUENCE OF STATIC PRESSURE TO RED BLOOD CELL DAMAGE UNDER SHEAR RATE CONDITONS

Yasuda, T.; Shimokasa, K.*; Funakubo, A.**; Miyawaki, F.**; Fukui, Y.**; Higami, T.***; Kawamura, T.****

ASAIO Bioengineering Abstracts
Free

Tokyo Denki University Frontier R&D

*Polytechnic University.

**Tokyo Denki University

***Hyogo Heart and Brain center at Himeji

****Hyogo Health Science Center.

Background: The causes of hemolysis due to physical forces are still unclear. In order to investigate the effect of static pressure and shear rate on hemolysis, we performed in vitro experiment.

Materials and methods: An apparatus consisted of a rotational viscometer, a pressure chamber and a heater was used at in vitro test. The rotational viscometer, which applied shear rate (0, 500, 1500s−1) to bovine blood, was set into the pressure chamber. The pressure chamber was connected to the air compressor to adjust the pressure levels inside of the chamber respectively (0,200,400, 600mmHg). The heater was used to maintain the constant temperature at 28 ± inside the chamber. The experiments were performed at 6 times for each condition and the duration was 120 minutes.

Results: It was not observed any significant hemolysis under the condition of the pressure levels between 0 and 200 mmHg and all of shear rates. Hemolysis with shear rate of 1500 s−1 was more than six times higher than that of 0 and 500 s−1 (P0.001) when the pressure level was 600 mmHg. On the other hand, significant differences in hemolysis were measured between 200 and 600 mmHg (P0.001) when shear rate was 1500s−1.

Conclusions: In conclusion, the results shown that the red blood cell damage depended on shear rate level and pressure level. In addition, it was identified that the damage of red blood cell under high shear rate might effect pressure levels.

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