Epidemiology and outcomes associated with surgical site infection following bariatric surgery

Surgical site infection (SSI) is a frequent problem complicating bariatric surgery. However, the potential risk factors, risk stratification, and outcomes of SSIs in this patient population remain poorly defined. The aim of this prospective case-control study was to characterize better the risk factors and to improve risk stratification for SSIs following bariatric surgery.

Patients studied had SSI following Roux-en-Y gastric bypass surgery (RYGBS) between November 2006 and March 2009 at Harper University Hospital and were each matched with 3 controls based on type of operative procedure, surgeon, and year of surgery. Thirty-day outcomes included mortality, hospital readmissions, outpatient procedures, and emergency room visits. A scoring system (BULCS score) was compared with the National Nosocomial Infections Surveillance system risk index using logistic regression.

In multivariate analysis, duration of surgery (odds ratio [OR], 3.3; 95% confidence interval [CI]: 1.62-6.74), diagnosis of bipolar disorder (OR, 3.341; 95% CI: 1.0-12.27), use of prophylactic antibiotics other than cefazolin (OR, 4.2; 95% CI: 1.47-11.69), and sleep apnea (OR, 1.8; 95% CI: 1.05-2.97) were significantly associated with SSI. Patients with SSI were more likely to have return emergency visits (OR, 4.96; 95% CI: 2.9-8.48), readmission (OR, 6.53; 95% CI: 3.44-12.42), and outpatient procedures following surgery (OR, 4.75; 95% CI: 1.32-17.14) than were controls without SSI. The BULCS score was a stronger predictor of SSI than the National Nosocomial Infections Surveillance system (C-statistic, -0.62 vs 0.55, respectively).

SSI following bariatric surgery was associated with receipt of antibiotic prophylaxis other than cefazolin and comorbid conditions including sleep apnea and bipolar disorder. The BULCS score performed favorably as a predictor and risk adjuster for SSI following bariatric surgery. SSI was associated with increased health care resource utilization.