MEDIASTINITIS AFTER CARDIAC-SURGERY - A 1 0-YEAR REVIEW (1985-1995)

From June 1985 to May 1995, 9,814 patients were operated for a cardiac procedure with cardiopulmonary by-pass. Mean age was 61,3 years. The most frequent procedure was coronary surgery (45 %), followed by valvu lar surgery (34 %) then combined surgery (11 %) and other surgery (4 % ). 66 cases of mediastinitis were observed: 38 from June 1985 to May 1 990 (first group), 28 from June 1990 to May 1995 (second group). The c hanges between the two groups was antibiotic prophylaxis using Cefurox ime in the first group and Cefamandole in the second and also an impai rment of general status of the patients in the second group. Staphyloc occus remains the most frequent organism in both groups and for Gram n egative bacteria was less frequent in the second group. Several risks factors mediastinitis were identified (males, emergency, diabetes mell itus, obesity, redo, patient of first group, duration of Cardiopulmona ry by pass for 100 minutes, mechanical ventilation grater than 48 hour s) and the most important factor was the need for mechanical ventilati on for more than 48 hours. The mortality rate was 39.4% (26 patients). Identified risk factors of mortality were age over 65 years, females, poor constitution, and cardio/thoracic ratio > 0.55. Conclusion: Medi astinitis after cardiac surgery remains a serious complication. In thi s series we observed a decrease of mediastinitis rates, especially in the second group (p < 0.001). In high risk patients, specific preopera tive methods of patient care may be able to prevent such complications . When mediastinitis appears, and when debridement is necessary, a cov er procedure seems necessary in elderly or poor constitution patients.