From 1960 through 1975, 337 patients with surgically treated acute fracture of the hip received subcutaneously administered aqueous heparin sodium to prevent thromboembolic episodes. Four hundred and three patients received no heparin. Their incidence of fatal pulmonary embolism was 3.5 percent. Ninety-five patients receiving the original “small dose” heparin regimen from August 1960 to November 1967 had a 4.2 percent incidence of fatal thromboembolism. These had been administered heparin 8-10 hours or less before surgery. Beginning November 1967 the “small dose” heparin schedule was altered in hip fracture patients to start heparin prophylaxis immediately following hospital admission. One hundred and forty-seven patients treated with the latter schedule had 0.0 percent fatal thromboembolism with the dose modified according to a coagulation time test. The patients received 2,500 units on admission and every 6 hours until the day before operation. Then they were given 5,000 to 10,000 units. 8 to 10 hours before surgery and 2,500 units every 6 hours after surgery until they were fully mobilized. The altered “small dose” heparin regimen adequately monitored by the blood coagulation test, the Dale and Laidlaw Coagulometer, proved highly effective as measured by fatality rates.
Prevention of Fatal Pulmonary Thromboembolism by Heparin Prophylaxis after Surgery for Hip Fractures