Background: The optimal management of aspirin and clopidogrel therapy before surgery in patients with acute coronary syndrome is uncertain. Aspirin and clopidogrel within 5 days of surgery increases postoperative bleeding and reexploration. However, in acute coronary syndrome patients the risk of bleeding must be balanced against the risks of discontinuing the treatment and delaying surgery.
Methods: From June 2002 to July 2003, patients undergoing urgent coronary artery bypass graft surgery (CABG) for acute coronary syndrome were randomly assigned to one of two groups. The treatment group remained on aspirin and clopidogrel therapy till surgery, receiving intraoperative aprotinin. The placebo group received placebo for 5 days before surgery and received placebo infusions intraoperatively. Platelet reactivity in response to adenosine diphosphate was assessed by whole blood single-platelet counting. Of the 88 patients eligible, 50 entered the study.
Results: Postoperative blood loss was significantly greater in the placebo group than in the treatment group (702 +/- 120 mL versus 446 +/- 62 mL, p = 0.004). This difference was observed as early as 8 hours postoperatively (385 +/- 66 mL versus 266 +/- 36 mL, p = 0.03). Patients in the placebo group also required more blood transfusions (1 +/- 0.3 units versus 0.3 +/- 0.2 units, p = 0.03). Three patients in each group underwent surgical reexploration for bleeding.
Conclusions: The strategy of continuing aspirin and clopidogrel therapy with intraoperative aprotinin reduces postoperative blood loss, transfusion requirements, prevents delay to surgical treatment, and may prevent major adverse cardiac events before surgery.