Surgical site infection rates following cardiac surgery: the impact of a 6-year infection control program

BACKGROUND: To evaluate the impact of an infection control program on surgical site infections (SSIs) complicating cardiac operations. METHODS: Prospective cohort study of patients undergoing cardiac operations. Interventions included prospective surveillance, povidone-iodine scrub showers, depilation before surgery, administration of preoperative antibiotic prophylaxis in the operating room, and postdischarge follow-up. Logistic regression models were fitted to assess infection rates over time, adjusting for factors known to affect SSI rates. RESULTS: The overall SSI rate for 2051 procedures was 10.4%. Rates of superficial and deep incisional SSIs remained unchanged over the study period. The rates of all organ/space infections, mediastinitis, and SSIs because of methicillin-resistant Staphylococcus aureus during the first 2 years were 3.25%, 2.22%, and 1.48%, respectively, and they decreased to 1.17%, 0.73%, and 0.73%, respectively, by the end of 2002 (P = .01, P = .01, and P = .09, respectively). The adjusted odds ratios for these 3 types of infection at the end of 2002 compared with December 31, 1998, were 0.19 (95% confidence interval [95% CI]: 0.07-0.48), 0.20 (95% CI: 0.06-0.66), and 0.28 (95% CI: 0.08-0.97), respectively. CONCLUSION: We observed significant reductions in organ/space infection rates, particularly mediastinitis. These differences remained significant when adjusted for potential confounding variables.