title: Predictors of unanticipated admission following ambulatory surgery in the pediatric population: a retrospective case-control study.
abstract: BACKGROUND
  Ambulatory surgery plays an important role in pediatric anesthesia. However, it is difficult to predict which patients will experience complications. Age >80, ASA class 3 or 4, duration of surgery >3 h, and BMI 30-35 are independent predictors of unanticipated admission in adults. In this study, we retrospectively evaluate risk factors for unanticipated admission, following ambulatory surgery in children.
  
  
  METHODS
  All ambulatory patients requiring unanticipated admission between 2005 and 2013 were compared to a random sample of patients not requiring admission in this case-control study. Demographic data, surgical information, medications, intraoperative events, and patient comorbidities were collected from both groups. The reason for admission was classified according to five subtypes. Multiple conditional logistic regression was used to assess factors associated with unanticipated admissions.
  
  
  RESULTS
  The incidence of unanticipated admission was 0.97% (213). Of these, 47% (98) was anesthesia related. Age <2 years (odds ratio [OR] 4.26 95% CI 1.19-15.25), ASA 3 class (OR 3.77 95% CI 1.46-9.71), duration of surgery >1 h (OR 6.54 95% CI 3.47-12.33), completion of surgery >3 pm (OR 2.17 95% CI 1.05-4.51), orthopedic (OR 2.52 95% CI 1.03-6.20), dental (OR 0.21 95% CI 0.06-0.81), ENT (OR 6.47 95% CI 2.99-14.03) surgery, intraoperative events (OR 4.45 95% CI 1.35-18.12), and OSA (OR 6.32 95% CI 1.54-25.94) were factors associated with unanticipated admission.
  
  
  CONCLUSIONS
  The incidence of unanticipated admission in children following ambulatory surgery is low. Age, ASA class, duration, and time of completion of surgery are predictors common to pediatrics and adults. Interestingly, intraoperative complications, OSA, and type of surgery (ENT, orthopedic, dental) are specific to pediatrics.
authors.affiliation: Department of Anesthesia, McMaster University, Hamilton, ON, Canada.
authors.forename: Amanda
authors.initials: A
authors.lastname: Whippey
authors.affiliation: Department of Anesthesia, McMaster University, Hamilton, ON, Canada.
authors.forename: Gregory
authors.initials: G
authors.lastname: Kostandoff
authors.affiliation: Department of Anesthesia, McMaster University, Hamilton, ON, Canada.
authors.forename: Heung K
authors.initials: HK
authors.lastname: Ma
authors.affiliation: Department of Anesthesia, McMaster University, Hamilton, ON, Canada.
authors.forename: Ji
authors.initials: J
authors.lastname: Cheng
authors.affiliation: Department of Anesthesia, McMaster University, Hamilton, ON, Canada.
authors.forename: Lehana
authors.initials: L
authors.lastname: Thabane
authors.affiliation: Department of Anesthesia, McMaster University, Hamilton, ON, Canada.
authors.forename: James
authors.initials: J
authors.lastname: Paul
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000556:Ambulatory Surgical Procedures / Q000706:statistics & numerical data*; D002170:Canada; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007431:Intraoperative Complications / Q000453:epidemiology*; D008297:Male; D061646:Operative Time; D010343:Patient Admission / Q000706:statistics & numerical data*; D011183:Postoperative Complications / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors; D013514:Surgical Procedures, Operative / Q000706:statistics & numerical data
keywords: ambulatory surgical procedures; comorbidity; obstructive sleep apnea; pediatric; perioperative period; unanticipated admission