We aimed to compare the efficacy of short-term (<24 hours) versus longer-term antibiotic prophylaxis (≥24 hours) in open heart surgery.
The optimal duration of antibiotic prophylaxis for adults undergoing cardiac surgery is unknown and guideline recommendations are inconsistent.
We searched MEDLINE, EMBASE, CINAHL, and CENTRAL for parallel-group randomized trials comparing any antibiotic prophylaxis administered for <24 hours to any antibiotic prophylaxis for ≥24 hours in adult patients undergoing open heart surgery. Reference lists of selected articles, clinical practice guidelines, review articles, and congress abstracts were searched. Study selection, data extraction and assessment of risk of bias were performed independently by 2 reviewers.
Of the 1338 citations identified by our search strategy, 12 studies involving 7893 patients were selected. Compared with short-term antibiotic prophylaxis, longer-term antibiotic prophylaxis reduced the risk of sternal surgical site infection (SSI) by 38% (risk ratio 1.38, 95% confidence interval (CI) 1.13–1.69, P = 0.002) and deep sternal SSI by 68% (risk ratio 1.68, 95% CI 1.12–2.53, P = 0.01). There were no statistically significant differences in mortality, infections overall and adverse events. Eleven of the trials were at high risk for bias due to limitations in study design.
Perioperative antibiotic prophylaxis of ≥24 hours may be more efficacious in preventing sternal SSIs in patients undergoing cardiac surgery compared to shorter regimens. The findings however are limited by the heterogeneity of antibiotic regimens used and the risk of bias in the published studies.
*Department of Clinical Epidemiology and Biostatistics
†Michael G. DeGroote Institute for Infectious Disease Research
‡Department of Medicine
§Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada.
Reprints: Mark Loeb, MD, MSc, Departments of Pathology and Molecular Medicine & Clinical Epidemiology and Biostatistics, McMaster University, MDCL 3203, 1200 Main St W, Hamilton, ON, Canada L8N 3Z5. E-mail: firstname.lastname@example.org.
Supported by a research scholarship from the Swiss National Science Foundation (PBBSP3-124436) (Dominik Mertz). Jennie Johnstone receives salary support from the McMaster University Infectious Diseases Bayer Healthcare Research Fellowship.
An abstract of this study was presented at the 50th Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC); Boston, MS, USA, in September 2010.
The authors have no conflicts of interest to declare.