Open-heart experience in infants using normothermia and deep hypothermia.

During the 9-year period from 1967 through 1975, 124 open-heart operations were performed on infants less than 1 year of age with 35 operative deaths (28%). Ninety-seven of these procedures used continuous cardiopulmonary bypass with normothermia or mild hypothermia, and 27 were done under deep hypothermia and circulatory arrest. Mortality and morbidity were similar regardless of the operative technique, although deep hypothermia facilitated the repair of complex lesions. The highest mortality occurred in infants less than 3 months of age. Respiratory insufficiency, usually requiring prolonged ventilatory support, occurred only among infants who had pulmonary overcirculation or congestion prior to operation. Adequacy of intraoperative repair and postoperative care were the major determinants of survival.