Prevention of venous thromboembolism with low doses of heparin in urologic patients.

The effectiveness of low doses of heparin was investigated for the prevention of clinically manifested thromboembolic disease. In the group of 125 patients, who received 5,000 units of subcutaneous heparin two hours before the operation, and postoperatively 15,000 units per day for seven to ten days, deep vein thrombosis was not observed, and in only 1 patient (0.8%) pulmonary embolism was suspected. Of 216 patients from the control group, pulmonary embolism was clinically diagnosed in 4 (1.9%), deep vein thrombosis in 7 (3.4%), and in 2 patients (0.9%) fatal pulmonary embolism was found at autopsy. The difference between total thromboembolic disease of the control group (6.2%) and heparinized group was highly significant (p less than 0.02). Postoperative bleeding was seen two times more often in the heparin group, but bleeding was not severe and was easily controlled.