title: A nested case-control study to determine the incidence and factors associated with unanticipated admissions following day care surgery.
abstract: OBJECTIVE
  Day care surgery offers respite from hospitalisation for specific surgical procedures and has many advantages. However, occasionally patients who undergo such surgery require hospitalisation for unanticipated complications. We aimed to determine their incidence and to identify factors associated with unanticipated admissions in a tertiary care hospital in South India.
  
  
  METHODS
  During the 3-month study, 63 cases requiring admission and 126 randomly selected controls were taken from the 776 procedures that were performed were compared. The variables studied were patients' demographic characteristics, pre-operative medical illness, personal habits, American Society of Anesthesiologists status, the diagnosis and surgical procedures, time since last meal, duration of anaesthesia and surgery, experience of the surgeon and anaesthetist, and intraoperative management (techniques, drugs, monitoring, etc.). Univariate and bivariate statistics were used to determine factors associated with unanticipated admissions.
  
  
  RESULTS
  The incidence of unanticipated admissions following day care surgery was 8.11%. The reasons for admission were anaesthetic (33.33%), surgical (15.87%), medical (6.34%) and social (44.44%). The factors significantly associated with unanticipated admissions included duration of anaesthesia more than 50 min (odds ratio [OR]: 3.179; 95% confidence interval [CI]: 1.503-6.722), and starting the last case after 3 pm (OR: 10.095; 95% CI: 2.418-42.148).
  
  
  CONCLUSIONS
  Unanticipated admissions following day care surgery occur mainly due to anaesthetic, surgical, medical and social reasons.
authors.affiliation: Department of Neurological Sciences, Neurosciences Critical Care Unit, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Madhurita
authors.initials: M
authors.lastname: Singh
authors.affiliation: Department of Anaesthesia, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Manickam
authors.initials: M
authors.lastname: Ponniah
authors.affiliation: Department of Psychiatry, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: K S
authors.initials: KS
authors.lastname: Jacob
keywords: Day care surgery; day surgery; nested case–control study; unanticipated admissions