72. Value of postoperative hyperglycemia for outcome of coronary artery bypass grafting surgery

Abstract

To determine the frequency of postoperative (PO) hyperglycemia in non-diabetic patients underwent Coronary artery bypass grafting (CABG) surgery and to evaluate its predictability for the outcome of these patients. Patients & Methods: The study included all patients assigned for CABG surgery and had no previous history of diabetes mellitus with preoperative fasting blood glucose of 180 mg/dl. Patients were categorized according RBG into: Normoglycemics had RBG <180 mg/dl and Hyperglycemics had RBG <180 mg/dl. Intraoperative data included frequency of CABG with beating heart and number of internal mammary artery graft used, aortic artery clamping, CPB and total operative times. Postoperative data included the frequency of hyperglycemic patients, occurrence of PO morbidities and mortality. All hyperglycemic patients received insulin infusion adjusted to achieve RBG level of 126–179 mg/dl. Results: All patients had significantly higher postoperative RBG levels compared to preoperative levels. Forty-three patients were hyperglycemic, while 57 patients were considered normoglycemic. Throughout ICU and hospital stay, 31 patients developed morbidities and 4 patients died with significantly higher frequency of additional morbidities and mortalities in hyperglycemic versus normoglycemic patients. There was positive significant correlation between the frequency of PO morbidities and mortality and extent of PO hyperglycemia, aortic clamping, CPB and total operative times. ROC curve and regression analyses showed that the extent of PO hyperglycemia, aortic clamping, CPB and total operative times are the significant predictors for morbidities and mortalities. Conclusion: PO hyperglycemia showed deleterious effects on outcome of CABG patients manifested as increased frequency of morbidities and mortalities during ICU and hospital stay and the extent of hyperglycemia could be considered as independent predictor of worsened outcome. The applied management policy allowed reduction of blood glucose levels without inducing hypoglycemia with subsequent improved outcome.