title: Unplanned reoperations: is emergency surgery a risk factor? A cohort study.
abstract: BACKGROUND
  Unplanned reoperations have been proposed as a quality indicator in surgery but have not been studied extensively, especially concerning risk factors.
  
  
  METHODS
  This was a prospective cohort study in a third-level general surgery service. Data regarding patients operated on between July 2007 and February 2008 and followed up for 30 postoperative days were collected. Unplanned reoperations were the primary end point. The secondary end points were 30-d mortality and length of stay. A multivariate logistic regression analysis evaluated the hypothesis that patients operated on in emergency conditions had a greater chance of being reoperated on, after adjusting for relevant covariates.
  
  
  RESULTS
  There was a 5.9% cumulative incidence of unplanned reoperations. Patients operated on in emergency conditions had a 1.79 crude relative risk (RR) (95% confidence interval [CI], 1.15-2.78) of reoperation. Reoperated patients' RR of mortality was 8.94 (95% CI, 6.11-13.07). The mean postoperative hospital stay was 3d for patients who were not reoperated on and 19d for those who were reoperated on (P=0.00001). The logistic regression model gave a 2.83 odds ratio (95% CI, 1.65-4.87) for reoperation on emergency patients when adjusted for age, gender, body mass index, American Society of Anesthesiology classification, intraoperative inotropic use, and operation complexity.
  
  
  CONCLUSIONS
  Tertiary general surgery service patients had a significantly increased risk of being reoperated on if the initial surgery was an emergency surgery compared with elective surgery. Unplanned reoperations led to a significantly increased mortality risk and a longer postoperative hospital stay, which could be regarded as warning signs in the care of surgical patients.
authors.affiliation: Department of Surgery, Clinical Research Institute, Universidad Nacional de Colombia, Bogotá, Colombia. oaguevarac@unal.edu.co
authors.forename: Oscar A
authors.initials: OA
authors.lastname: Guevara
authors.forename: Jorge A
authors.initials: JA
authors.lastname: Rubio-Romero
authors.forename: Ariel I
authors.initials: AI
authors.lastname: Ruiz-Parra
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D004638:Emergency Treatment / Q000009:adverse effects*; D023381:Endpoint Determination; D005260:Female; D013502:General Surgery / Q000706:statistics & numerical data*; D006801:Humans; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology* / Q000601:surgery*; D011446:Prospective Studies; D012086:Reoperation / Q000401:mortality / Q000706:statistics & numerical data; D012307:Risk Factors; D015996:Survival Rate; D055815:Young Adult