Predictors of infection in post-coronary artery bypass graft surgery.

Background: Although coronary artery bypass grafting (CABG) is a good alternative therapy in severe arterial disease, it may evolve with complications, especially infections.

Objectives: To determine the incidence of infection in post-CABG and its clinical predictors in a cardiology reference center in Brazil.

Methods: Cohort study. Data were collected from all patients undergoing CABG between January/2004 and February/2006, excluding emergency surgery, absent record of glucose blood levels preoperatively and infection prior to surgery.

Statistical Analysis: Student's t test, chi square, logistic regression.

Results: We evaluated 717 patients, 61.9 ± 11 years old, 67.1% were men, 29.6% with diabetes, of whom 137 (19.1%) developed infection (62% respiratory, 25% superficial wound, 9.5% urinary, 3.6% deep wound). Diabetes was more prevalent in those who developed infection, as well as prolonged time of indwelling central venous catheter (79.3 ± 40.5 vs. 61.0 ± 19.3 hours, P<0.001). After multivariate analysis (model adjusted for dyslipidemia, hypertension, smoking and leukocytes), both diabetes (OR 4.18 [2.60-6.74]), prolonged central venous line (OR 1.019 [1.00-1.02] and cardiac catheterism (OR 2.03 [1.14-3.60] remained predictors of infection. While diabetes is associated with a higher percentage of infections (P <0.001), preoperative serum glucose was not associated with increased risk of infection.

Conclusions: Diabetes and permanence of central venous catheters were associated with development of infection in post-CABG. The preoperative blood glucose was not a predictor of risk of infection. It is probably necessary to study with greater detail glycemic control trans- and post-operatively.