Predicting factors from unexpected hospital admission following ambulatorysurgery

BACKGROUND: Hospital admission following ambulatory surgery is a valid meas ure of morbidity and a quality indicator. To improve the efficiency of an a mbulatory surgery unit it is essential to study the factors associated with unexpected hospital admission. Our goal was to analyze the association of age, ASA, type of surgical and anesthetic procedures, surgical duration, pa in, vomiting and surgical and anesthetic complications with unexpected hosp ital admission. PATIENTS AND METHODS: Retrospective case-control study. The cases were all patients who underwent ambulatory surgery in the Viladecans Hospital (Barce lona, Spain) from October 1990 till May 1996 (h = 6,071), cases (n(1) = 93) , controls (n(0) = 552). Logistic regression models with a predictive varia ble and multiple logistic regression were obtained. OR and 95% CI were calc ulated. RESULTS: Age was not significant for admission. ASA greater than status 1 ( OR: 3.4 [1.4-9]); p = 0.01), the procto-perineo-sacrococcygeal procedures h ave significant risk (OR: 35 [4-304]; p < 0.00001), and other types of surg ery were not significant. General, spinal anaesthesia and non-spinal locore gional ones with sedation were not significant (p > 0.2), but spinal anesth esia with deep sedation carried a significant risk (OR: 20 [3-122]; p < 0.0 0001). Surgical duration higher than 40 min (OR: 22 [5-94]; p < 0.00001), p ain (OR: 12 [3-55]; p < 0.00001) and vomiting (OR: 8(up arrow)5 [1,2-59]; p = 0.03) were significant factors in predicting hospital admission. CONCLUSIONS: The factors related with unexpected hospital admission followi ng ambulatory surgery were: surgical and anesthetic complications, pain, pr octo-perineal and sacrococcigeal procedures, spinal anesthesia with profoun d sedation and a surgical duration time higher than 40 min.