title: Prediction of surgical site infection after colorectal surgery.
abstract: BACKGROUND
  Surgical site infection (SSI) after colorectal surgery is a frequent complication associated with substantial morbidity. Our objective was to identify surgical predictors of SSI in patients undergoing colorectal surgery using a retrospective case-control design.
  
  
  METHODS
  Randomly selected patients from all those undergoing colorectal surgery (2007-2013). Cases were patients who developed SSI within 30 days. Controls were patients who did not develop SSI within 30 days. Patients undergoing multiple procedures during a single surgical intervention were excluded. SSI was diagnosed according to Centers for Disease Control and Prevention definitions. The main outcome measures were SSI, surgical variables, and cumulative survival (Kaplan-Meier method). Variables considered predictors were compared using log-rank test.
  
  
  RESULTS
  Of 911 patients undergoing colorectal surgery, 221 developed SSI (24.3%; 95% confidence interval, 24.0-24.6). On univariate analysis, significant risk factors for SSI were: female sex (P = .02), >72 hours preoperative stay (P = .04), open surgery (P = .08), incision class: contaminated and dirty (P = .001), and emergency procedures (P = .006). On multivariate analysis, significant independent predictors of SSI and survival were dirty surgery (hazard ratio [HR], 2.12; P = .015), contaminated surgery (HR, 1.74; P = .009), female sex (HR, 1.58; P = .003), open surgery, (HR, 1.51; P = .015) and >72 hours preoperative stay (HR, 1.48; P = .024).
  
  
  CONCLUSIONS
  Dirty or contaminated surgery, female sex, open surgery, and >72 hours preoperative stay were significant predictors of SSI.
authors.affiliation: Servicio Microbiología y Medicina Preventiva, Hospital Universitario de Canarias, Santa Cruz de Tenerife, Spain. Electronic address: yanetcub@yahoo.es.
authors.forename: Yanet
authors.initials: Y
authors.lastname: Pedroso-Fernandez
authors.affiliation: Unidad de Investigación, Hospital Universitario NS Candelaria, Santa Cruz de Tenerife, Spain.
authors.forename: Armando
authors.initials: A
authors.lastname: Aguirre-Jaime
authors.affiliation: Servicio Microbiología y Medicina Preventiva, Hospital Universitario de Canarias, Santa Cruz de Tenerife, Spain.
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Ramos
authors.affiliation: Servicio Microbiología y Medicina Preventiva, Hospital Universitario de Canarias, Santa Cruz de Tenerife, Spain.
authors.forename: Miriam
authors.initials: M
authors.lastname: Hernández
authors.affiliation: Servicio Microbiología y Medicina Preventiva, Hospital Universitario de Canarias, Santa Cruz de Tenerife, Spain.
authors.forename: Milagros
authors.initials: M
authors.lastname: Cuervo
authors.affiliation: Servicio de Cirugía General y Digestiva, Hospital Universitario de Canarias, Santa Cruz de Tenerife, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Bravo
authors.affiliation: Servicio de Cirugía General y Digestiva, Hospital Universitario de Canarias, Santa Cruz de Tenerife, Spain.
authors.forename: Angel
authors.initials: A
authors.lastname: Carrillo
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D003107:Colorectal Surgery / Q000009:adverse effects*; D003661:Decision Support Techniques; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D013530:Surgical Wound Infection / Q000453:epidemiology*; D055815:Young Adult
keywords: Incidence; Predictors; Surgical site infection