518. Increased Risk of Surgical Site Infection among Breast Conserving Surgery Re-Excisions
Session: Poster Abstract Session: Surgical Site Infections
Thursday, October 3, 2013
Room: The Moscone Center: Poster Hall C
Background: Revision operations are generally thought to be associated with increased risk of surgical site infection (SSI) compared with primary operations, possibly due to fibrosis resulting in greater surgical complexity. This may not be true for a simpler procedure such as breast conserving surgery (BCS), in which re-excision is relatively common.

Methods: We conducted a retrospective cohort study of women aged 18 – 64 years from 6/29/04 – 12/31/10 with at least one BCS procedure using private insurer claims data. Individual procedures were identified from facility and/or provider claims using ICD-9-CM procedure or CPT-4® codes for BCS. We required at least 180 days of insurance coverage with no BCS in order to identify the index BCS; all subsequent re-excisions within 180 days of the index BCS were included. SSIs ≤ 90 days after procedure were identified by ICD-9-CM diagnosis codes, and the attributable surgery selected based on the onset of SSI compared to the BCS date(s). A chi-square test was used to compare the incidence of SSI after the index BCS compared to subsequent procedures within 180 days.

Results: 65,050 women with 71,329 BCS procedures were identified, with 8.9% of women having >1 BCS (range 1-5). Women with >1 BCS were older (mean 51.3 vs. 46.7 years, p<0.001) and more likely to have invasive breast cancer (84.1% vs. 26.3%, p<0.001) than women with only 1 BCS within 180 days. The incidence of SSI was 1.30% (846/65,050) for the index BCS, 2.25% (130/5,790) for the second procedure, and 2.45% (12/489) for ≥3 procedures (p<0.001). The risk of SSI associated with re-excision remained significantly higher when the population was restricted to women with invasive breast cancer (2.55% (135/5,286) vs. 1.88% (385/20,436), p=0.002).

Conclusion: We found a higher risk of SSI after re-excision BCS compared with a single BCS. The risk of SSI associated with re-excision remained significant after restricting the population to women with invasive breast cancer.

Katelin B. Nickel, MPH1, David K. Warren, MD, MPH1, Julie A. Margenthaler, MD, FACS2, Anna E. Wallace, MPH3, Daniel Mines, MD, MSCE3, Victoria J. Fraser, MD1 and Margaret A. Olsen, PhD, MPH1,4, (1)Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO, (2)Division of General Surgery, Washington University School of Medicine, St. Louis, MO, (3)HealthCore, Inc., Wilmington, DE, (4)Division of Public Health Sciences, Washington University School of Medicine, St. Louis, MO

Disclosures:

K. B. Nickel, None

D. K. Warren, None

J. A. Margenthaler, None

A. E. Wallace, None

D. Mines, None

V. J. Fraser, None

M. A. Olsen, None

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