Evaluation of mini-dose heparin administration as a prophylaxis against postoperative pulmonary embolism: a...

A prospective double-blind study was instituted in a group of 150 general surgical patients to test the effectiveness of mini-dose heparinization in the pre- and postoperative periods. There was a 21 per cent reduction in the incidence of deep venous thrombosis in the heparin treated group. A radiopharmaceutical imaging technique with 99m-technetium macroaggregated albumin was used to evaluate the deep venous system. The procedure proved to be simple, safe, and painless; however, it was difficult to differentiate venous stasis from deep venous thrombosis. A negative study was good evidence that deep venous thrombosis did not exist. An additional benefit of this procedure was that a perfusion lung study could be obtained which provided additional information regarding pulmonary embolism without injecting additional radiopharmaceutical. Again, the negative perfusion lung study provided more information.