Is it possible to cure mediastinitis in patients with major postcardiac surgery complications?

Background. The prognosis for mediastinitis after cardiac operation has improved during the last two decades, but most series do not include patients who already have a major postoperative complication when the infection developed. Methods. Our 9-year prospective study of 371 consecutive patients with mediastinitis compared the characteristics of patients admitted to the intensive care unit primarily for mediastinitis with those who developed mediastinitis after intensive care unit admission for severe postoperative organ failure. Results. We identified 323 (87%) primary and 48 (13%) secondary mediastinitis patients. The incubation time for mediastinitis was longer for secondary mediastinitis patients, despite similar initial operations. Staphylococcus aureus was responsible for approximately 60% of the episodes in both groups; however, the incidence of methicillin resistance was 2.5 times higher in secondary mediastinitis patients ( p < 0.0001). The mediastinitis cure rate was similar for both groups. However, intensive care unit mortality (63% versus 21%), duration of mechanical ventilation (40 versus 9 days), and length of intensive care unit stay (53 versus 28 days) were significantly higher for secondary mediastinitis patients ( p < 0.0001). Conclusions. The presence of a prior major postoperative complication does not alter the cure rate of mediastinal infections, but does greatly reduce the survival rate.