[Effect of desmopressin (DDAVP) on blood platelet parameters in vivo and in vitro]

Coagulation assays including DDAVP test were carried out in 15 patients preoperatively, evaluating several parameters of platelets during the assays. After DDAVP infusion we observed a decreased spontaneous aggregation in whole blood, an increased retention to glass beads, and in a number of cases a raised in vitro-formation of thromboxane. By application of DDAVP, a significant enhancement of spontaneous aggregation in whole blood and left shift to smaller volumes of the platelet volume distribution were demonstrated in vitro. It is concluded that DDAVP has an indirect inducing effect on aggregation, probably by release of ADP from red blood cells.