The arterial switch operation has become the preferred procedure for surgical management of transposition of the great arteries. We conducted a retrospective evaluation of our experience in sixty-one infants with transposition from January, 1997 to July, 2003 in order to determine the factors that are associated with a prolonged postoperative course following the arterial switch operation. Factors independently associated with a prolonged postoperative stay in the cardiac intensive care unit included prematurity, difficulty feeding, capillary leak, need for preoperative inotropic support, and postoperative infectious complications. Future research designed to minimize the impact of capillary leak and postoperative infectious complications is warranted. In addition, based on these results, our practice has evolved to initiate enteral feedings in the preoperative period if feasible and to resume enteral feedings as soon as possible following surgery.