People who take aspirin on a regular basis for Heart disease should stop the drug 5 days before elective surgery to ensure that their blood is able to clot normally on the operative day.

In addition to its pain-relieving effects, aspirin inhibits the activity of platelets, cell-like structures in the blood that play a key role in clotting. This effect is beneficial for preventing clot-related diseases, such as Heart attack and Stroke, but it could spell problems during surgery.

Deciding when to stop aspirin therapy before surgery is a balancing act. If the drug is stopped too early, the patient could be at increased risk for clot-related problems. Conversely, discontinuing the drug too late, places the patient at risk for bleeding problems during the operation.

Dr. H. Paul Redmond, from Cork University Hospital in Ireland, and colleagues assessed clotting ability in 51 healthy volunteers who were randomly treated with aspirin, at one of two standard doses, or inactive “placebo” for 14 days. Data from 38 subjects was available for analysis.

The researchers’ findings appear in the Journal of the American College of Surgeons.

Clotting ability fell as expected in the aspirin groups during treatment, the investigators point out. Within 144 hours of stopping aspirin therapy, all of the subjects displayed normal clotting ability. This period before normal clotting returned was about the same regardless of the aspirin dose given.

Based on these findings, “we believe that aspirin therapy should be discontinued 5 days before elective surgery and the operation planned for the sixth day after treatment cessation. This should allow physicians and surgeons to minimize the risks of stopping aspirin without increasing the risk of excessive perioperative bleeding,” the authors conclude.

SOURCE: Journal of the American College of Surgeons, April 2005.