Risk factors for mortality in patients with mediastinitis after cardiac surgery

Summary 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.