Predictors and outcomes of gastrointestinal complications in patients undergoing coronary artery bypass graft surgery: A prospective, nested case-control study

The aim of this study was to assess risk factors and outcomes of gastrointestinal (GI) complications in patients undergoing coronary artery bypass surgery (CABG). We conducted a nested case-control study from a 9-year hospitalization cohort (n = 7,345) in which data were collected prospectively. Patients developed GI complications (n = 66) and controls did not (n = 330). Cases were matched to controls 1:5 on type of surgery. We examined 16 risk factors and 14 outcomes. Five risk factors proved significant in predicting GI complications. Patients were more likely to be older than age 70, to be on dialysis, to have left ventricular hypertrophy, and to be on anticoagulants; the procedure was also more likely to be urgent. There was no significant difference between the cases and controls for the remaining 11 risk factors. We also computed correlation coefficients among the significant variables; using regression analysis, we found that patients undergoing CABG had a threefold increase in the risk of GI complications if they were older than age 70 (odds ratio [OR] 1.06, 95% CI 1.03 to 0.97), if they were on dialysis (OR 1.87, 95% CI 1.98 to 1.22), and if their procedure was urgent (OR 1.91, 95% CI 1.07 to 3.4). Eleven outcomes proved significant. Patients with GI complications ran a greater risk of mortality; required more additional procedures; suffered arrhythmia that required treatment; and were more likely to have neurologic, pulmonary, renal, and sternal wound complications. They also had greater length of hospitalization, intensive care unit length of hospitalization, ventilator time, and postoperative creatine phosphokinase levels. In patients undergoing CABG surgery, urgency of the procedure, age greater than 70 years, and dialysis all significantly increased the risk of a GI complication. Patients with GI complications also experienced more negative outcomes.