Endpoints The primary outcome will be the chest blood output during the first 24 hours. Size sample calculation : bleeding with aspirin alone is estimated around 400±200 mL after CABG (5). Excessive bleeding will be defined by an increment of at least 25% of this basal value collected through chest tubes during the first 24 postoperative hours. Secondary outcomes will be the rate of re-exploration for excessive bleeding, transfusion requirement, prolonged mechanical ventilation (>10 h), and intensive care unit length of stay (>72 h).