Risk factors for mortality in patients with mediastinitis after cardiac surgery

Background. - Patients with mediastinitis after cardiac surgery have higher morbidity and mortality. Aims. - Describe the characteristics of patients with mediastinitis, determine the mortality within one month, and assess the risk factors associated with mortality. Methods. - Retrospective cohort study including all adult patients with mediastinitis during the 2002-2006 period at the Nantes University Hospital. Multivariate analysis by logistic regression and Kaplan-Meier curve of survey were done. Results. - Nearly 5574 patients were operated during the study period, with a mediastinitis incidence rate of 0.7%, 28 patients (72%) had coronary artery bypass graft. The mortality rate increased from de 12.8% during hospital stay to 20.5% within one year. Only two deaths were associated with mediastinitis. The occurrence of a co-infection was the only independent risk factor associated with mortality (OR 13, P < 0.04). The instantaneous risk of death was increased by 7 in patient with co-infection, particularly mechanical ventilator-associated pneumonia (CR 1,97). Conclusion. - Mortality varied according to the duration of surveillance, and mediastinitis was not the major cause of death. Mechanical ventilator-associated pneumonia after mediastinitis increases the mortality and needs specific prevention. (c) 2009 Elsevier Masson SAS. All rights reserved.