Studies on platelet membrane glycoproteins and platelet function during hemodialysis.

Hemodialysis only partially corrects the defects in platelet function associated with uremia. Platelet contact with the artificial surfaces of the dialysis filter during hemodialysis can itself cause platelet activation, degranulation, and loss of platelet membrane glycoproteins. Although the transient platelet dysfunction that occurs after platelet contact with foreign surfaces during cardiopulmonary bypass has been well characterized, there has been no such investigation of hemodialysis. In this study of hemodialysis patients, bleeding times (BT) and the response of their platelets to thrombin, ristocetin, and collagen were measured before, immediately after, and in some patients, the day after hemodialysis. In addition, membrane glycoproteins in platelets obtained at these time intervals were studied using fluorescein isothiocyanate (FITC) conjugated monoclonal antibodies (mAb) CD42b (anti-GPIb), CD41a (anti-GPIIb/IIIa), and CD62 (anti-P-selectin), with flow cytometry. BT was significantly prolonged, and response to thrombin and ristocetin was significantly decreased immediately after hemodialysis (P