[Hemostatic control in platelet dysfunction and abnormality by DDAVP].

DDAVP infusion shortens the bleeding time in patients with some types of platelet dysfunction and may be useful for hemostatic control. In order to clarify the mechanism of DDAVP to correct or bypass the release defect, we examined the effect in 17 patients with prolonged bleeding time, i.e., 11 with various kinds of platelet dysfunction, 4 with idiopathic thrombocytopenic purpura (ITP), 1 with chronic myelocytic leukemia (CML), and in an aspirin-ingested volunteer. DDAVP shortened the bleeding time in 9 patients with platelet dysfunctions, one with ITP, and the one aspirin ingested volunteer. No improvement was found in the aggregability and the retention rates, and no signs of activation occurred in the platelet shape. The RCof was elevated in all of the patients after the infusion. Our data suggests that DDAVP improves the hemostasis through primary aggregation and release of dense bodies, and not directly through an increase of RCof.