Platelet Function and Markers of Hemostatic Activation in Plasma Donors

Abstract

Purpose: The aim of this study was to investigate the effects of plasmapheresis procedure on in vivo platelet activation, platelet function, blood coagulation, and fibrinolysis. Participants and Methods:16 healthy donors were subjected to automated plasma donation using cell separator Autopheresis C®. 500 ml of plasma were collected per procedure. Samples of donors’ blood for routine hematological measurements and the measurement of P-selectin were obtained immediately before donation as well as 1 min, 24 h, and 48 h after donation. Fibrinogen concentrations, platelet aggregation, thrombin-antithrombin III (TAT) complexes and D dimers were measured before plasmapheresis as well as 1 min and 48 h after plasmapheresis. Results:Measurements of CD62-positive platelets and platelet aggregation using ADP, epinephrine, and arachidonic acid showed no significant differences between pre- and postdonation values (p > 0.05). Mean platelet volume (p < 0.01) as well as fibrinogen concentrations (p < 0.05) and D dimers (p <0.05) were reduced after plasmapheresis. Plasma concentrations of circulating TAT complexes increased signifi-cantly after plasmapheresis (p < 0.001). Concentrations of fibrinogen and TAT complexes returned to the baseline values within 48 h while concentrations of D dimers remained lower 48 h after the completition of the procedure. Conclusion:On the basis of the evaluated testing there was no evidence that plasmapheresis adversely affected platelet-dependent primary hemostasis. Decreased concentrations of D dimers after plasmapheresis suggest no increase in fibrinolytic activity. Nonspecific loss of circulating D dimers during the procedure is a likely explanation. Observed changes of coagulation parameters suggest that plasmapheresis procedure has a transient influence on hemostasis, probably without clinical significance.