Infectious mediastinitis after cardiac operations: computed tomographic findings

BACKGROUND: Infectious mediastinitis after cardiac operations is of great concern to cardiac surgeons because of its poor prognosis. Prompt surgical interventions such as debridement and irrigation are the key to treatment of infectious mediastinitis. METHODS: We surveyed retrospectively the cases of 722 consecutive cardiac surgery patients at our hospital. Mediastinitis developed in 21 patients after the cardiac operation. We performed computed tomography in 11 of these patients before resternotomy and in 10 patients as the control 2 to 3 weeks after the cardiac operation. RESULTS: Mediastinal soft tissue swelling was seen in 7 patients, bilateral pleural effusion was found in 9 patients, sternal dehiscence or sternal erosion was observed in 8 patients, and subcutaneous fluid accumulation was found in 7 of the mediastinitis group. Unilateral pleural effusion was seen in 6 and bilateral effusion in 1, and mediastinal soft tissue swelling was seen in 1 patient of the control group. CONCLUSIONS: Our study showed that mediastinal soft tissue mass combined with bilateral pleural effusion can be a characteristic computed tomography finding in poststernotomy infectious mediastinitis, and that chest computed tomography is more sensitive to detecting sternal dehiscence, sternal erosion, and subcutaneous fluid accumulation.