DDAVP-induced correction of prolonged bleeding time in patients with congenital platelet function defects.

In 37 patients with prolonged bleeding time, where thrombocytopenia, von Willebrand's disease or deficiency of other coagulation factors could be excluded, we have evaluated the effect of a DDAVP-infusion (0.2 ug/kg) together with tranexamic acid (10 mg/kg). Patients with acquired impairment of primary hemostasis were not included, except two cases where this could have been a contributing factor. The bleeding time was completely normalized in 27 cases and partially corrected in three more patients. The predominant feature among those, who did not respond, was a pattern compatible with thrombasthenia or cyclooxygenase deficiency, as assessed by platelet aggregation studies. Among the patients, in whom DDAVP was effective, this drug was thereafter successfully used as an alternative to blood products in 8 cases during and after surgery or delivery.