1404. National Healthcare Safety Network (NHSN) Surgical Site Infection (SSI) Pathogen Distribution and Surgical Care Improvement Project (SCIP) Antimicrobial Prophylaxis Regimens (AMPR) reported for Coronary Artery Bypass Graft (CABG) and Arthroplasty Procedures, 2006-2008
Session: Oral Abstract Session: Predicting and Preventing SSIs
Sunday, October 23, 2011: 7:45 AM
Room: 157ABC
Background: SSI following CABG and primary hip/knee arthroplasty, the most commonly reported procedures to NHSN, cause significant morbidity.  In order to inform future prevention strategies, we compared procedure-specific SSI pathogen distributions from NHSN to AMPRs reported through SCIP during the same time period.

Methods: NHSN data from January 1, 2006 through December 31, 2008 were analyzed to determine the distribution of pathogens causing complex SSIs following CABG and primary hip/ knee arthroplasty.  In a separate analysis, AMPR data reported through SCIP for the same time period were stratified by procedure; individual AMPRs were categorized according to published guidelines. Categories included “standard” (cefazolin or cefuroxime), “beta-lactam allergy” (vancomycin or clindamycin +/- an aminoglycoside), and “extended” (vancomycin or an aminoglycoside +cefazolin or cefurozime).  The expected spectrum of activity for reported AMPRs was compared to SSI pathogen distributions.

Results: During the study period 752 hospitals reported to NHSN 411,912 CABG and arthroplasty procedures with 4,046 complex SSIs.  Among the 4,146 isolates reported, methicillin-sensitive S. aureus (n=923, 22.3%), methicillin-resistant S. aureus (n=779, 18.8%), coagulase-negative staphylococci (n=696, 16.8%), and Enterococcus spp. (n=272, 6.6%) were the most common.  AMPRs for 1,774,161 CABG and arthroplasty procedures performed in 3,517 hospitals during the study period were analyzed.  Standard regimens, used in 75.1% of procedures, would be expected to have activity against only 37.4-42.2% of the SSI pathogens reported. Beta-lactam allergy regimens, used in 11.4% of procedures, would have activity against 64.5-96.5% of SSI isolates, and extended regimens, used in 8.0% of procedures, would have activity against 76.3-96.5% of reported pathogens.

Conclusion: Cefazolin or cefuroxime are the AMPRs used for the vast majority of patients undergoing CABG and primary arthroplasty in the US, but most complex SSIs following these procedures are caused by pathogens resistant to these antibiotics. Alternative strategies are needed to identify patients at high risk of these SSIs in order that AMPRs can be modified appropriately.

Subject Category: N. Hospital-acquired and surgical infections, infection control, and health outcomes including general public health and health services research

Sandra Berríos-Torres, MD1, Dale Bratzler, DO, MPH2, Sarah Yi, PhD1, Allen Ma, PhD2, Yi Mu, PhD3, Jonathan Edwards, MS1, Liping Zhu, MD, MPH1 and John Jernigan, MD, MS1, (1)Centers for Disease Control and Prevention, Atlanta, GA, (2)Oklahoma Foundation for Medical Quality, Oklahoma City, OK, (3)CDC, Atlanta, GA


S. Berríos-Torres, None

D. Bratzler, None

S. Yi, None

A. Ma, None

Y. Mu, None

J. Edwards, None

L. Zhu, None

J. Jernigan, None

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