Effects of centrifugation speed on platelet aggregation activity

Introduction: The method of platelet preparation is one of the factors which affect the quality and yield of platelet during its storage. Previous studies have shown that the use of high and low centrifugal speed during preparation of platelet concentrates can change platelet aggregation activity. In this research, effect of high and low centrifugation speed on platelet aggregation activity in responding to various agonists and platelet yield were studied. Materials and Methods: Firstly, for determination of yield in platelet rich plasma, 11 units of whole blood were centrifuged at 2160 g (method I) and also 11 units were centrifuged at 2050 g (method II) for 4.0 min and the mean platelet yield of two methods were determined. Again for evaluation platelet aggregation, at the second step, 8 units of whole blood were centrifugedat 2160 g and another 8 units were centrifuged at 2050xg similar to above conditions and for these 16 samples, aggregation tests were performed at the presence of ADP, arachidonic acid, collagen and ristocetin agonists. Results: the mean platelet yield of first and second method was found 52% and 69%, respectively. Percentage of the mean platelet aggregation activity of platelet rich plasma samples with responding to ADP, arachidonic acid, collagen and ristocetin agonists in the first method were found 42.2, 26.9, 28.4 and 72.2, whereas at the second method were observed 66.6, 85.6, 83.3 and 84.4, respectively. Conclusion: The results showed that the use of low speed at 2050 g in comparison with high speed at 2160xg can significantly increase platelet yield and platelet aggregation activity with responding to ADP, arachidonic acid, collagen and ristocetin agonists and thus it can improve quality of platelet rich plasma preparation.