In a prospective study, 254 of 5649 unselected patients scheduled for surgery at our hospital were identified preoperatively as having either acquired (n=182) or inherited (n=72) impaired primary hemostasis (platelet dysfunction including von Willebrand disease). All patients were initially pretreated with desmopressin (DDAVP). Response to DDAVP or subsequent treatment(s) was defined as correction of any one of the abnormal PFA-100 platelet function tests. The non-responders were additionally treated with tranexamic acid or aprotinin; those with von Willebrand disease (vWD) received factor VIII concentrates with von Willebrand factor (vWF). Those still unresponsive to therapy received conjugated estrogens and, as a last attempt, a platelet transfusion. The administration of DDAVP led to a correction of platelet dysfunction in 229 of the 254 patients treated (90.2%). Tranexamic acid was effective in 12 of 16, aprotinin in 3 of 5, and factor VIII concentrates with vWF in all 4 patients with unresponsive to DDAVP. The remaining 6 patients were pretreated with conjugated estrogens, and 2 of these patients were additionally treated with platelet transfusion. The frequency of blood transfusion was lower, but not statistically significant (9.4% vs. 12.2%: p = 0.202) in preoperatively treated patients with impaired hemostasis than in patients without impaired hemostasis. In a retrospective group, the frequency of blood transfusion was statistically significant higher (89.3% vs. 11.3%: p < 0.001) in patients without preoperative correction of impaired hemostasis than in patients without impaired hemostasis. Preoperative correction of impaired primary hemostasis is possible in nearly all patients affected, and results in a reduction of homologous blood transfusions.