Differential platelet receptor expression following hydroxyethyl starch infusion in thrombocytopaenic orthotopic liver transplantation recipients

BACKGROUND AND OBJECTIVE: Platelet function abnormalities influence the haemostatic defect in patients with liver failure. Patients after orthotopic liver transplantation present thrombocytopaenia associated with bleeding problems, which may be aggravated by the interaction of hydroxyethyl starches with platelets. METHODS: From 12 patients after liver transplantation venous blood samples (3 mL) were taken before, 20 and 120 min after infusion of hydroxyethyl starch of medium molecular weight (200 kDa/0.5) 6% 10 mL kg(-1) over a period of 30 min. Surface expression of glycoprotein IIb/IIIa and P-selectin were quantified by flow cytometry as well as the percentage of platelet-leucocyte complexes. RESULTS: A significant decrease of P-selectin expression following administration of hydroxyethyl starch after 120 min (89.1 +/- 4.2%, P = 0.029) and a corresponding significant reduction in the formation of platelet-monocyte complexes (81.1 +/- 7.8%, P = 0.001) were observed. There was no alteration in the glycoprotein IIb/IIIa expression after hydroxyethyl starch infusion. CONCLUSIONS: Infusion of hydroxyethyl starch 200 kDa/0.5 in clinically relevant doses does not alter glycoprotein IIb/IIIa expression in thrombocytopaenic patients with pre-existing platelet dysfunction after orthotopic liver transplantation. Accordingly, infusion of hydroxyethyl starch may have a beneficial effect on microvascular graft perfusion through the resulting haemodilution and reduced P-selectin expression with subsequent reduced leucocyte-platelet complexes and endothelial adhesion.