title: Risk factors for severe sepsis in secondary peritonitis.
abstract: BACKGROUND
  The incidence and risk factors for severe sepsis (SS, organ failure associated with infection) in the context of peritonitis are not well established; thus, it is not clear which patients require more aggressive operative or pharmacologic intervention. We set out to determine risk factors for severe sepsis in a large cohort of patients with intra-abdominal infection.
  
  
  METHODS
  Patients admitted for peritonitis over a four-year interval were identified using a Washington State administrative hospital discharge database. This cohort was identified by ICD-9 CM diagnoses and diagnosis-related group (DRG) assignment. Patients with organ failure were identified by ICD-9 CM diagnoses codes using a previously validated classification scheme. Independent risk factors for SS were identified using stepwise Poisson regression.
  
  
  RESULTS
  A total of 11,202 patients with peritonitis were identified, 11% of whom developed SS. The crude relative risk of death in patients with SS was 13 (95% CI, 11.1-15.2) times greater than those without. Severe sepsis was present in 424 (62%) of the 686 decedents. Multivariate analysis showed that source of infection, extent of peritonitis, increasing age, and pre-existing organ dysfunction were independently associated with SS.
  
  
  CONCLUSIONS
  Severe sepsis complicates the course of 11% of all patients with peritonitis. Risk factor analysis identifies a subset of patients at greatest risk for severe sepsis. These are the patients who should be targeted for evaluation of novel pharmacologic interventions or more aggressive surgical intervention.
authors.affiliation: Division of General and Trauma Surgery, Harborview Medical Center, and the Department of Surgery, University of Washington, Seattle, Washington 98104-2499, USA.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Anaya
authors.forename: Avery B
authors.initials: AB
authors.lastname: Nathens
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001424:Bacterial Infections / Q000209:etiology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009102:Multiple Organ Failure / Q000209:etiology*; D010538:Peritonitis / Q000382:microbiology* / Q000601:surgery; D011183:Postoperative Complications / Q000382:microbiology*; D012189:Retrospective Studies; D012307:Risk Factors; D018805:Sepsis / Q000209:etiology*