STERNITIS AND MEDIASTINITIS AFTER CORONARY-ARTERY BYPASS-GRAFTING - ANALYSIS OF RISK-FACTORS

As part of a quality control program, we analyzed possible risk factor s in the development of sternitis and mediastinitis after coronary art ery bypass grafting. From 1 January 1990 through 31 December 1991, 1,3 68 consecutive coronary artery bypass grafting procedures were perform ed at our institution, either alone or in combination with other proce dures. Twenty-three patients (1.7%) developed sternitis and/or mediast initis; 7 (30.4 %) of these patients died in an early postoperative ph ase. Univariate analysis revealed the following statistically signific ant (p less-than-or-equal-to 0.05) risk factors: perfusion time, lengt h of stay in operating room of longer than 5 hours 30 minutes, presenc e at the operation of a certain surgical resident, revision for bleedi ng, and postoperative mechanical ventilation lasting longer than 72 ho urs. After multivariate analysis, statistically significant independen t risk factors were: diabetes mellitus, recent cigarette-smoking, reop eration, presence of a certain surgical resident at the operation, rev ision for bleeding, and length of mechanical ventilation of longer tha n 72 hours. The use of both internal thoracic arteries was not, in thi s study, shown to be an independent risk factor We conclude that altho ugh the technique of using both internal thoracic arteries for myocard ial revascularization carries no extra risk by itself in the developme nt of sternitis or mediastinitis, associated factors such as prolonged stay in the operating room and reoperation could be responsible for a higher frequency of sternitis-mediastinitis in patients who have unde rgone this procedure. Therefore, it is advisable to use this technique selectively in high-risk patients. Close surveillance and reporting o f wound infections is mandatory to detect risk factors related to the surgical staff (such as Staphylococcus aureus dissemination).