OBJECTIVE: Mediastinitis is a serious complication of open-heart surgery, with an incidence that varies from 0.4% to 5%, mortality from 10% to 47% and a high morbidity rate. OBJECTIVE: To identify preoperative and trans-operative risk factors of mediastinitis after open-heart surgery in our hospital. METHOD: This was a prospective study of 1298 patients submitted to the open-heart surgery in São Lucas hospital in the period from March 1997 to May 2000. Nine potential risk factors associated with mediastinitis were studied (obesity, diabetes mellitus, chronic obstructive pulmonary disease -COPD-, internal mammary artery, cardiopulmonary bypass time, smoking, gender, ejection fraction and previous heart surgery) using univariate analysis, where necessary followed by multivariate logistic regression. RESULTS: Of the 1298 studied patients, 62.6% were men and 18.3 suffered from diabetes. Thirty-eight patients (2.9%) presented with mediastinitis postoperatively, and six (15.8%) of these died. Four variables identified as risk factors by univariate analysis (p<0.05) and were after analysed by logistic regression. Three variables were identified as independent predictors of mediastinitis: obesity (p=0.008), COPD (p=0.007) and diabetes mellitus (p= 0.009), even when gender and age were analysed. The internal mammary artery graft was observed as risk predictor only when associated to the obesity. CONCLUSION: In our hospital, mediastinitis occurs most frequently in patients suffering from obesity, diabetes, and/or COPD and in the obese patients in which internal mammary artery was used.
Mediastinitis; Mediastinal infection; Cardiac surgery; Surgical infection
