Influence of desmopressin acetate on homologous blood requirements in cardiac surgical patients pretreated with aspirin.

Conflicting results have been reported concerning the effect of the synthetic vasopressin analog desmopressin acetate (DDAVP) on perioperative bleeding and homologous blood requirements in cardiac surgery. Because patients preoperatively treated with platelet-inhibiting drugs are at increased risk of perioperative bleeding, the blood-saving effect of DDAVP was investigated in 40 male patients undergoing primary myocardial revascularization. All patients had taken aspirin within the last 5 days prior to surgery. In a double-blind, randomized trial, the effects of DDAVP (0.3 microgram/kg of body weight) were compared to those of saline placebo on postoperative blood loss and the need to replace blood products. To evaluate the drug's influence on the coagulation and fibrinolytic systems, von Willebrand factor (vWF), the activities of tissue plasminogen activator (tPA) and plasminogen activator inhibitor (PAI 1), and the split products of cross-linked fibrin (D-dimers) were investigated. The total homologous blood requirement was significantly lower in DDAVP recipients (median 2, range, 0 to 5 U) compared to placebo (median 3.5, range, 0 to 8 U; P < 0.05). Although at all points of measurement (intraoperative and postoperative) transfusion requirement was less in the DDAVP group, hematocrit values of these patients always exceeded those of the placebo group, this difference being significant at the end of the operation. Because no difference in postoperative blood loss was found, the markedly reduced transfusion requirement of the DDAVP-treated patients is explained either by reduced intraoperative bleeding or by a reduced hematocrit of the chest-tube blood.(ABSTRACT TRUNCATED AT 250 WORDS)