TREATMENT OF SEVERE PLATELET DYSFUNCTION AND HEMORRHAGE AFTER CARDIOPULMONARY BYPASS - REDUCTION IN BLOOD PRODUCT USAGE WITH DESMOPRESSIN

[摘要] Impairment of platelet function commonly occurs after cardiopulmonary bypass, and may result in substantial bleeding. Because desmopressin acetate (a synthetic analogue of vasopressin) shortens bleeding time in a variety of platelet disorders, a controlled clinical trial of intravenous desmopressin was performed in 39 patients with excessive mediastinal bleeding (> 100 ml/h) and a prolonged template bleeding time (> 10 minutes) more than 2 hours after termination of cardiopulmonary bypass. Twenty-three desmopressin recipients and 16 control patients (no desmopressin) were similar in surgical procedure, pump time, platelet count, template bleeding time and amount of bleeding before therapy (p = NS). Compared with the control group, the patients receiving desmopressin (20 .mu.g; mean 0.3 .mu.g/kg) utilized fewer blood products (29 .+-. 19 versus 15 .+-. 13 units/patient; p < 0.05), especially platelets (12 .+-. 9 versus 4 .+-. 7 units/patient; p = 0.004), while achieving a similarly effective reduction in mediastinal bleeding (4.8- to 4.3-fold, p = 0.001 for both). Severe platelet dysfunction was partially corrected within 1 hour after desmopressin infusion, during which interval no blood products were administered: the template bleeding time shortened (from 17 to 12.5 minutes, p < 0.05), whereas the platelet count remained unchanged (at 96 .+-. 35 and 105 .+-. 31 .times. 103/min, p = NS). The plasma levels of two factor VIII components increased: procoagulant activity (VIII:C) from 0.97 .+-. 0.43 to 1.52 .+-. 0.74 units/ml (p < 0.05) and von Willebrand factor (VIII:vWF) from 1.28 to 1.78 units/ml (p < 0.05); these increases correlated with the shortening of the bleeding time (p < 0.01). In 10 (83%) of 12 patients who had continued bleeding requiring reoperation, a localized bleeding source was identified. Generalized mediastinal oozing at reoperation was noted in only one patient each in the desmopressin and control group (p = NS). In conclusion, administration of desmopressin reduced transfusion requirements of blood loss in patients with severe platelet dysfunction and bleeding after cardiopulmonary bypass. Desmopressin simultaneously shortened the bleeding time and increased circulating plasma levels of the factor VIII complex (procoagulant activity and von Willebrand factor), suggesting that the beneficial effects of desmopressin were mediated in part by an elevation of plasma von Willebrand factor. Failure of medical therapy (continued generalized bleeding requiring reoperation) was infrequent, but the finding of a localized bleeding source in a high proportion of reoperations emphasizes the need for exquisite surgical hemostasis at initial operation.

[发布日期] 1987-05-01