Results:

There were 448 patients who had undergone S2P between 2008-2012. Of these, 57% were between 4-6 months old, with a median weight of 6 kg, a median LOS of 8 days, and a median intensive care unit (ICU) stay of 4 days. By univariate analysis, age outside of the 4-6 month range, a major extracardiac anomaly, a smaller center volume, a breathing-related concern or need for diuretics during interstage monitoring, daily outpatient surveillance of weight or oxygen saturation, need for additional procedures during S2P (atrial septectomy, atrioventricular [AV] valve repair, pulmonary artery [PA] plasty, but NOT aortic arch repair), postoperative need for vasoactive drugs, ICU readmission after transfer to the ward, and need for postoperative procedures (pericardiocentesis or thoracentesis, cardioversion, tracheostomy) were associated with a prolonged LOS. The type of Norwood I procedure (Blalock-Taussig shunt vs. right ventricle-PA conduit), impaired interstage weight gain, or pre-Glenn saturation <75% did not significantly increase LOS. By multivariate analysis, only the following variables were predictive of prolonged LOS: 1) the need for re-intervention after S2P, 2) nonoral methods of nutrition, and 3) postoperative complications (seizures, need for pacing or dialysis, infection, or vocal cord injury).