Effects of desmopressin acetate (DDAVP) and dextran on hemostatic and thromboprophylactic mechanisms.

The effects on hemostatic and thromboprophylactic mechanisms of intravenous desmopressin (DDAVP, 0.3 micrograms/kg) and dextran 40 and 70 given both separately and in various combinations were evaluated in five male volunteers. Dextran did not inhibit the DDAVP-induced hemostatic changes. The dextran-induced decrease in platelet adhesiveness and the prolonged bleeding time were totally reversed by DDAVP. Hematocrit decrease was seen after both drugs, lasting longer when they were combined. We conclude that DDAVP and dextran may be used concomitantly, each with maintained beneficial properties. DDAVP will still act hemostatically by increasing platelet adhesiveness, factor VIII and von Willebrand factor and by shortening the dextran-induced prolongation of bleeding time. Dextran and DDAVP may even have additive antithrombotic effects due to the DDAVP-induced stimulation of the fibrinolytic activity, which is not inhibited by dextran, and to rheologic changes such as hematocrit decrease induced by both drugs.