Mediastinitis post revascularización miocárdica: impacto del cambio de profilaxis antibiótica en la fundación Cardioinfantil 2012 - 2013
INTRODUCTION. Post coronary artery bypass graft (CABG) mediastinitis is an uncommon but potentially lethal infection. In recent years a rising trend of this infection has been observed at the Fundación Cardioinfantil (FCI), that it is why, a change on antimicrobial prophylaxis protocol, from cephalosporins (standard therapy) to vancomycin-gentamicin (second-line therapy) was made. However, the impact of these measures is not yet known. OBJETIVE: To determine whether the change of antibiotic prophylaxis in patients undergoing to CABG influences a decrease on mediastinitis incidence from 2012 to 2013. METHODS: A retrospective cohort study was conducted by evaluating the rates of mediastinitis after isolated CABG in patients underwent 2 different types of antimicrobial prophylaxis (cephalosporins vs. vancomycin-gentamicin). Patterns of susceptibility and resistance of pathogens most frequently found in mediastinitis, and mortality of this disease were also described. RESULTS: The pathogens most frequently isolated in mediastinitis were Staphylococcus aureus and Klebsiella pneumoniae, in a monomicrobial pattern in most of patients. Some pathogens with resistance profiles of clinical importance as extended-spectrum beta-lactamases in Gram-negative, and methicillin resistance in Gram positive cocci were found. The relative risk (RR) of mediastinitis of the cohort exposed to vancomycin-gentamicin compared to cephalosporin cohort was 0,9 with 95% CI: 0,28 to 3,28. CONCLUSION: Microbial epidemiology of mediastinitis at FCI did not significantly differ from the literature reports. The antimicrobial prophylaxis therapy with vancomycin-gentamicin in patients undergoing to isolated CABG did not reduce the mediastinitis incidence. Return to prophylactic therapy with cephalosporins has been proposed to FCI.