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Aspirin-induced prolongation of bleeding time and perioperative blood loss
Insights
Aspirin therapy for hip replacement patients prolonged bleeding times but did not increase perioperative blood loss. Higher aspirin doses did not show paradoxical shortening of bleeding times.
Area of Science:
- Orthopedic Surgery
- Pharmacology
Background:
- Total hip replacement is a common surgical procedure.
- Effective anticoagulation is crucial for preventing perioperative complications.
Purpose of the Study:
- To investigate the effect of different aspirin dosages on bleeding times and perioperative blood loss in patients undergoing total hip replacement.
Main Methods:
- 129 patients undergoing total hip replacement were randomized to receive either 1.2 g/day or 3.6 g/day of aspirin.
- Bleeding times were measured at baseline, 2 hours post-dose, and after 3-5 days of therapy.
- Perioperative blood loss was compared to historical controls.
Main Results:
- Aspirin treatment significantly prolonged bleeding times compared to baseline at both dosage levels.
- No paradoxical shortening of bleeding time was observed even at the higher dose (3.6 g/day).
- Perioperative blood loss was not significantly increased in most subsets of aspirin-treated patients compared to historical controls.
Conclusions:
- Aspirin prolongs bleeding time in a dose-dependent manner in patients undergoing total hip replacement.
- The observed prolongation of bleeding time does not appear to translate to increased perioperative blood loss.
- Aspirin can be safely used for thromboprophylaxis in total hip replacement without a significant increase in surgical bleeding.
Abstract:
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.
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