Unanticipated admission after ambulatory surgery--a prospective study.

PURPOSE: To determine the incidence, the reasons, and the predictive factors for unanticipated admission after ambulatory surgery.
METHODS: Preoperative, intraoperative, and postoperative data were collected prospectively on 15,172 consecutive ambulatory surgical patients during a 32-month period. The data were built into a statistical model, and predictive factors were identified and classified.
RESULTS: The overall incidence of unanticipated admission was 1.42%. Admitted patients were more likely to be older, male, and ASA status II or III. Duration of anaesthesia was longer, and surgery was more likely to be completed after 3 pm. Length of stay in the Postanaesthesia Care Unit and the Ambulatory Surgery Unit was longer. Surgical reasons were cited in 38.1% of admitted patients; anaesthesia-related reasons were cited in 25%; social reasons accounted for 19.5%, and medical reasons for 17.2%. Ear, nose and throat (ENT) patients had the highest unanticipated admission rate (18.2%), followed by urology (4.8%) and chronic pain block (3.9%). Gynaecological patients had the lowest rate (0.4%). Among the predictive factors found were male, ASA status II and III, long duration of surgery, surgery finishing after 3 pm, postoperative bleeding, excessive pain, nausea and vomiting, and excessive drowsiness or dizziness.
CONCLUSION: Earlier operating time for certain surgical procedures, screening for proper support at home, and implementation of clinical pathways to deal aggressively with problems such as pain, nausea and vomiting should decrease the incidence of unanticipated admission.