High and low-dose aspirin prophylaxis against venous thromboembolic disease in total hip replacement.

Aspirin has been demonstrated to be an effective prophylactic agent against postoperative venous thromboembolic disease, but the optimum dosage is unknown. We compared the efficacy of daily doses of 3.6 grams of aspirin (high dose) with that of 1.2 grams (low dose) in 182 patients. All patients were more than forty years old and all underwent a total hip replacement. This randomized, prospective, double-blind study was done using only objective dta for diagnosis. Twenty-three (44 per cent) of fifty-two women who were treated with the low dose had thrombi, compared with eighteen (34 per cent) of fifty-three women who were given the high dose. Thrombi developed in thirteen (32 per cent) and in eighteen (49 per cent) of thirty-seven men who were given the high dose. There were no statistically significant differences among the four groups, nor was there a significant difference among the subgroups that were determined according to prior history of venous thromboembolic disease. Therefore, the higher dose of aspirin was neither more nor less effective than the lower dose. Our data continue to support the use of 1.2 grams in men.