Prevalence of Staphylococcus aureus nasal carriage and surgical site infection rate among patients undergoing elective cardiac surgery.

Abstract Background Nasal carriers of Staphylococcous aureus (SA) are at increased risk of postoperative surgical site infection. Nasal decolonization with mupirocin is recommended in patients undergoing cardiac surgery to reduce surgical site infection. These data are still lacking in Thailand. Therefore, we aimed to study the prevalence of SA nasal carriage in Thai patients undergoing elective cardiac surgery. The association of surgical site infection and SA nasal carriage was also examined. Methods This is a prospective cohort study of 352 patients who planned to undergo elective cardiac surgery. Nasal swab culture was performed in all patients preoperatively. Results Of 352 patients, 46 patients (13.1%) revealed positive nasal swab culture for methicillin-sensitive SA (MSSA), and one patient (0.3%) harbored methicillin-resistant SA (MRSA) strain. The incidence of superficial and deep surgical site infection was 1.3% and 0.3%, respectively. After multivariate analysis, SA nasal carriage was independently associated with superficial surgical site infection (Odds ratio, 13.04; 95% CI 1.28-133.27; P = 0.03). Conclusions Prevalence of MSSA and MRSA nasal carriage in Thai patients undergoing elective cardiac surgery was low. Incidence of surgical site infection was also very low in the studied population. Nevertheless, we found that SA nasal carriage increased risk of superficial surgical site infection.