Introduction Patients undergoing cardiac surgery with cardiopulmonary bypass (CPB) are at risk for microvascular bleeding. The frequency of excessive bleeding with CPB varies according to the definition used. Although a recent analysis indicated that 11% of patients have excessive bleeding after cardiac surgery1, only 5-7% have postoperative blood loss of more than 2 liters over a 24 hour period. (2) Excessive microvascular bleeding can result in re-exploration and prolonged hospitalization. If excessive bleeding is defined as patients who require re-exploration, two large series show that the incidence is between 3.6% and 4.2%. (3,4)
