Mediastinitis after aorto-coronary bypass surgery

Area of Science:

• Cardiovascular Surgery
• Infectious Disease
• Surgical Outcomes

Background:

• Mediastinitis is a serious complication following coronary artery bypass surgery (CABG).
• Identifying pre-operative and intra-operative risk factors is crucial for prevention and management.
• A closed irrigation/drainage system offers a treatment option for post-sternotomy mediastinitis.

Purpose of the Study:

• To determine risk factors associated with mediastinitis in patients undergoing isolated coronary artery bypass surgery.
• To evaluate the efficacy of a closed irrigation/drainage system for treating mediastinitis.

Main Methods:

• A retrospective analysis of 60 mediastinitis cases among 2512 CABG patients (1988-1995).
• Comparison of 20 potential risk factors between patients with and without mediastinitis.
• Treatment involved early reexploration, debridement, closed-circuit mediastinal irrigation/drainage, and antibiotics.

Main Results:

• Significant risk factors identified: diabetes mellitus (41.6% vs 18.8%), obesity (48.3% vs 15.2%), peripheral vascular disease (11.6% vs 4.0%), and double internal mammary artery (IMA) use (58.3% vs 23.5%).
• Lower incidence of poor left ventricular (LV) function in mediastinitis cases (18.3% vs 32.7%).
• Staphylococcus epidermidis was the most common pathogen (62.5%). Mortality was 1.7%, and renal failure occurred in 15%.

Conclusions:

• Diabetes mellitus, obesity, peripheral vascular disease, and the use of a double IMA are significant risk factors for mediastinitis post-CABG.
• The closed irrigation/drainage system is effective when combined with early diagnosis and reintervention.