Prevention of postoperative thromboembolism by dextran 70 or low-dose heparin.

The efficacy of intravenous infusion of dextran 70 or subcutaneous administration of low-dose heparin in preventing postoperative thromboembolic complications has been investigated in a prospective randomized trial. During part 1 of the study, 232 patients over the age of 40 years who were undergoing major gynecologic surgery underwent a complete test protocol. The 125I fibrinogen uptake test (FUT) was used for the diagnosis of deep vein thrombosis (DVT) in 117 patients in the dextran and 115 patients in the heparin group. Heparin was significantly more effective than dextran for reducing DVT (P less than .001). During part 2 of the study no FUT was done but the incidence of clinical and fatal pulmonary embolism (PE) and the number of complications were studied. Of 444 patients (parts 1 and 2) 1 fatal and 2 nonfatal pulmonary emboli were diagnosed. All the emboli occurred in the dextran group. The benefit: hazard ratio appeared to favor heparin for the prophylaxis of DVT.