Aspirin as an Antithrombotic Medication

IN 1977 an article in the Journal 1 reported that aspirin prophylaxis (600 mg twice daily) was effective against the development of postoperative venous thrombosis and pulmonary embolism in patients who had undergone total hip replacement. Postoperative venous thrombosis occurred in 23 of 51 patients given a placebo but in only 11 of 44 receiving aspirin. Treatment was initiated one day before surgery and was continued until radiographic phlebography — the diagnostic end point — had been completed (usually two weeks).The therapeutic use of aspirin in venous thrombosis seemed unorthodox, since venous thrombi consist mainly of a heterogeneous mass of . . .