Antimicrobial prophylaxis may not be the answer: Surgical site infections among patients receiving care per recommended guidelines

BackgroundIt is believed that compliance with all 3 components of perioperative antimicrobial prophylaxis, ie, timing, choice, and duration, yields greater reduction in surgical site infections (SSI).MethodsAn observational study was performed among patients in the surgical care improvement project at a tertiary public academic hospital in the United States. The rates of SSI among patients who received appropriate antimicrobial agent(s) per current guidelines were compared with patients who did not. Medical record review was performed to compare the clinical characteristics of patients with SSI (cases) and an equal number of patients without SSI (matched controls).ResultsFrom January 2008 to June 2009, 762 patients underwent 763 eligible surgical procedures. Forty-seven (6.2%) developed SSI. The rate of SSI in patients who received appropriate antimicrobial prophylaxis per guidelines was not different from those who did not (42/611, 6.9% vs 5/152, 3.3%, respectively; P value = .13). Patients with SSI were more likely to have an elevated body mass index (median and interquartile range in cases: 28.7 [27.0-34.9] vs 25.0 [22.4-30.4] in controls; P value = .02) and more likely to have diabetes (36% vs 9%, respectively; odds ratio, 5.71; 95% confidence interval: 1.43-22.8; P value = .02).ConclusionCompliance with timing, choice, and duration of antimicrobial prophylaxis as a whole did not lead to lower SSI. Elevated body mass index and diabetes were associated with a higher rate of SSI.