Inclusion Criteria:1) scheduled cardiac surgery with hypothermic CPB to repair either D-transposition of the great arteries (D-TGA) with intact ventricular septum (IVS) or ventricular septal defect (VSD), VSD with or without aortic arch obstruction (AAO), tetralogy of Fallot (TOF) with or without pulmonary atresia (PA), truncus arteriosus, total anomalous pulmonary venous return (TAPVR), or double outlet right ventricle (DORV), or to palliate hypoplastic left heart syndrome (HLHS) or other forms of single ventricle (SV) with AAO using the stage I (Norwood) operation, 2) age 1-45 days at surgery, 3) birth weight > 2.3 kg, and 4) a cranial ultrasound < 1 week prior to enrollment showing at most grade II hemorrhage in high risk patients -