Dual Topical Antibiotic Application Prior to Sternotomy Closure Reduces Sternal Wound Infection Rates: A Simple Solution to a Grave Morbidity

Background: A significant cohort of patients who undergo cardiac surgery suffer from diabetes and atherosclerosis. These patients have impaired tissue perfusion, hence a reduction in antibiotic concentration in the subcutaneous tissues at the side of the mammary artery harvesting. Topical application of gentamicin and vancomycin before wound closure broadens the antibiotic spectrum and reduces the incidence of deep sternal wound infection. In this article, we compare the use of single versus dual application of vancomycin and/or gentamicin in sternotomy wounds in a single tertiary center. Methods: An observational cohort analysis with three sequential patient groups (N = 2550) was performed at Ain Shams University Hospital in Cairo. A control group (N = 850), vancomycin only group (N = 850), and vancomycin plus gentamicin group (N = 850) were included in the study, during the three-year period from January 2017 to December 2019. Patients who had minimal access surgery were excluded from this study. The presence of an infected postoperative sternotomy wound was assessed in all patients. Results: The presence of an infected sternotomy wound (El Oakley class 2B) was present in 38 patients (4.5%) in the control group, in 19 patients (2.2%) in the vancomycin group, and in nine patients (1.1%) in the dual antibiotic group, respectively (P < .001). In contrast to the usual, we had a proliferous growth of gram-negative organisms 29 (3.4%) in the control group, 10 (1.2%) in the vancomycin group, and five (0.6%) in the dual antibiotic group, respectively (P < .001). Conclusion: Deep sternal wound infection is a major cause of post-cardiac surgery morbidity and prolonged hospital stay. Adding the simple step of topical application of vancomycin and gentamicin to the sternotomy wound at the end of the procedure appeared to significantly reduce deep wound infection rates.