515. Rates of Surgical Site Infection by Hernia Repair Site and Approach
Session: Poster Abstract Session: Surgical Site Infections
Thursday, October 3, 2013
Room: The Moscone Center: Poster Hall C
Background: The National Healthcare Safety Network (NHSN) does not stratify surgical site infection (SSI) rates after hernia repair based on anatomic site or laparoscopic vs. open approach. We investigated whether site and approach are important determinants of SSI risk for hernia repair.  

Methods: Using commercial insurer claims data, we conducted a retrospective cohort study of enrollees aged 6 months – 64 years with ICD-9-CM procedure or CPT-4® codes for open and laparoscopic umbilical, inguinal/femoral, and incisional/ventral hernia repair procedures from 1/1/2004 – 12/31/2010. SSIs ≤ 90 days after hernia repair and before a subsequent NHSN surgery were identified by ICD-9-CM diagnosis codes. Procedures in which preexisting SSI or septicemia was coded ≤30 days prior to the surgery date were excluded. Chi-square and Fisher's exact test were used to compare SSI incidence by anatomic site and approach.

Results: 120,127 hernia repair procedures were included in the analysis; 80% were male and the median age was 46 (interquartile range 35 – 55). The incidence of SSI differed significantly by anatomic site, with rates of 0.45% (352/77,746) for inguinal/femoral, 1.16% (288/24,928) for umbilical, and 4.10% (716/17,453) for incisional/ventral hernia repair. Compared with inguinal femoral hernia repairs, the relative risk (RR) of SSI was 9.06 (95% confidence interval (CI) 7.98 – 10.28) for incisional/ventral hernia repairs and 2.55 (95% CI 2.19 – 2.98) for umbilical hernia repairs. The incidence of SSI was higher for open surgery compared with laparoscopic surgery (1.26% (1,281/102,003) vs. 0.41% (75/18,124), p<0.001; RR 3.03 (95% CI 2.41 – 3.83)). Within anatomic sites, the incidence of SSI was significantly higher for open vs. laparoscopic incisional/ventral (4.19% (702/16,756) vs. 2.01% (14/697), p=0.005) and inguinal/femoral (0.48% (295/61,205) vs. 0.34% (57/16,541), p=0.020) hernia repair.

Conclusion: The incidence of SSI was higher after open hernia repair compared to laparoscopic procedures, and highest after incisional/ventral compared to umbilical and inguinal/femoral procedures. Our findings suggest that stratification of SSI rates by anatomic site and approach is important when comparing SSI rates between facilities.

Margaret A. Olsen, PhD, MPH1,2, Katelin B. Nickel, MPH1, Anna E. Wallace, MPH3, Daniel Mines, MD, MSCE3, Victoria J. Fraser, MD1 and David K. Warren, MD, MPH1, (1)Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO, (2)Division of Public Health Sciences, Washington University School of Medicine, St. Louis, MO, (3)HealthCore, Inc., Wilmington, DE


M. A. Olsen, None

K. B. Nickel, None

A. E. Wallace, None

D. Mines, None

V. J. Fraser, None

D. K. Warren, None

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