Study objective: To determine the incidence of and reasons for prolonged length of stay in the postanesthesia care unit and unplanned hospital admissions of children scheduled for outpatient surgery.

Design: Prospective, observational cohort study.

Setting: C. S. Mott Children's Hospital, a tertiary care setting.

Patients: 168 ASA physical status I, II, and III children (birth to 18 years), 130 of whom experienced a prolonged length of stay and 61 who had an unplanned hospital admissions.

Measurements and main results: 3.9% of annual outpatient population experienced a prolonged length of stay, and 1.9% had an unplanned outpatient admission. Prolonged length of stay was most commonly due to postoperative nausea and vomiting (19%) or respiratory complications (16%), whereas unplanned hospital admissions were primarily for respiratory or surgical reasons (32% and 30%, respectively). Higher ASA status had a significant direct relationship with the incidence of unplanned outpatient admission and respiratory complications. Although most families were satisfied with the length of their child's care, 28% of parents whose children were sent home after a prolonged length of stay would have preferred a short hospital admission, and 16% of parents of children with an unplanned hospital admission would have preferred a longer stay in recovery and discharge home.

Conclusion: Prolonged length of stay and unplanned hospital admissions were uncommon outcomes following pediatric outpatient surgery. However, the impact of such outcomes on hospital staffing and family convenience may have implications related to cost containment and patient satisfaction.