Aspirin-induced prolongation of bleeding time and perioperative blood loss.
One hundred twenty-nine patients undergoing total hip replacement were treated with aspirin at a level of either 300 mg four times a day (1.2 g/day) or 900 mg four times a day (3.6 g/day). Baseline bleeding times before aspirin treatment averaged 4.18 +/- 1.44 minutes. Two hours after 300 mg and 900 mg of aspirin, the bleeding times were 5.83 +/- 1.88 and 5.72 +/- 1.57 minutes, respectively. After three to five days of aspirin therapy at 1.2 g/day and 3.6 g/day, the bleeding times were 6.27 +/- 2.27 and 6.43 +/- 2.11 minutes, respectively. The bleeding times for all the aspirin-treated groups were longer than baseline times. No paradoxical shortening of the bleeding time was noted at the 3.6-g/day dose. Perioperative blood loss for those receiving aspirin was not increased in six of eight subsets by operation and anesthesia when compared with historical control subjects. Neither a bleeding time greater than ten minutes nor a prolongation of the bleeding time by aspirin of more than four minutes over baseline bleeding times was associated with increased perioperative blood loss.
D000284:Administration, Oral; D000328:Adult; D000368:Aged; D001241:Aspirin / Q000008:administration & dosage / Q000009:adverse effects*; D001760:Bleeding Time; D002986:Clinical Trials as Topic; D005260:Female; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D011897:Random Allocation
D001241:Aspirin