title: Thirteen years of surgical site infection surveillance in Swiss hospitals.
abstract: BACKGROUND
  Surveillance is an essential element of surgical site infection (SSI) prevention. Few studies have evaluated the long-term effect of these programmes.
  
  
  OBJECTIVE
  To present data from a 13-year multicentre SSI surveillance programme from western and southern Switzerland.
  
  
  METHODS
  Surveillance with post-discharge follow-up was performed according to the US National Nosocomial Infections Surveillance (NNIS) system methods. SSI rates were calculated for each surveyed type of surgery, overall and by year of participation in the programme. Risk factors for SSI and the effect of surveillance time on SSI rates were analysed by multiple logistic regression.
  
  
  RESULTS
  Overall SSI rates were 18.2% after 7411 colectomies, 6.4% after 6383 appendicectomies, 2.3% after 7411 cholecystectomies, 1.7% after 9933 herniorrhaphies, 1.6% after 6341 hip arthroplasties, and 1.3% after 3667 knee arthroplasties. The frequency of SSI detected after discharge varied between 21% for colectomy and 94% for knee arthroplasty. Independent risk factors for SSI differed between operations. The NNIS risk index was predictive of SSI in gastrointestinal surgery only. Laparoscopic technique was protective overall, but associated with higher rates of organ-space infections after appendicectomy. The duration of participation in the surveillance programme was not associated with a decreased SSI rate for any of the included procedure.
  
  
  CONCLUSIONS
  These data confirm the effect of post-discharge surveillance on SSI rates and the protective effect of laparoscopy. There is a need to establish alternative case-mix adjustment methods. In contrast to other European programmes, no positive impact of surveillance duration on SSI rates was observed.
authors: Department of Surgery, Geneva University Hospitals, Geneva, Switzerland.
authors: W
authors: W
authors: Staszewicz
authors: Service of Infectious Diseases, Central Institute of the Valais Hospitals, Sion, Switzerland.
authors: M-C
authors: MC
authors: Eisenring
authors: Department of Surgery, Mid-Valais Hospital Center, Sion, Switzerland; Department of Surgery, University Hospital of Lausanne, Lausanne, Switzerland.
authors: V
authors: V
authors: Bettschart
authors: Infection Control Program, Geneva University Hospitals, Geneva, Switzerland.
authors: S
authors: S
authors: Harbarth
authors: Service of Infectious Diseases, Central Institute of the Valais Hospitals, Sion, Switzerland; Service of Preventive Medicine, University Hospital of Lausanne, Lausanne, Switzerland. Electronic address: nicolas.troillet@hopitalvs.ch.
authors: N
authors: N
authors: Troillet
mesh_terms: D000328:Adult; D000368:Aged; D062665:Epidemiological Monitoring; D005260:Female; D006761:Hospitals; D006801:Humans; D017053:Infection Control / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011182:Postoperative Care / Q000379:methods*; D013530:Surgical Wound Infection / Q000453:epidemiology* / Q000517:prevention & control*; D013557:Switzerland / Q000453:epidemiology; D055815:Young Adult
keywords: Risk factors; Surgical site infection; Surveillance; Switzerland; Temporal trends