Methods: Between April 2009 and April 2011, consecutive 267 CABG patients who were subjected to intraoperative conservative glycemic control with intermittent boluses of insulin during surgery were retrospectively analyzed. The patients were classified as diabetic (n=118) and non-diabetic (n=149) patients. Then, the patients were divided into three subgroups as intraoperative mean blood glucose (MBG) concentration <150 mg/dL (group 1), 150-180 mg/dL (group 2), and >180 mg/dL (group 3). All recorded perioperative, intraoperative, and postoperative data were compared between diabetic and non-diabetic patients according to their intraoperative blood glucose levels.
Results: Among patients enrolled in the study, 44% were diabetic and 51.7% of diabetics and 11.3% of non-diabetics were in group 3. Of all patients, 29% had an intraoperative MBG of >180 mg/dL. Non-diabetic patients in group 3 had higher lactate levels (p=0.005), renal impairment (p=0.04), and mortality rates (p=0.03), compared to other groups and with diabetic patients in same group. The incidence of infectious events was higher in diabetic patients with MBG >180 mg/dL (p=0.037). A low positive correlation between MBG and lactate levels in non-diabetic patients (r=0.20), and between MBG and the length of stay in the intensive care unit in diabetic patients (r=0.25) was found.
Conclusion: Our study results demonstrate that intraoperative conservative glycemic control with intermittent boluses of insulin seems not to be sufficient in diabetic patients. Non-diabetic patients with higher lactate levels, renal impairment and mortality rates also necessitate effective glycemic control. Therefore, simple, safe and effective algorithms should be developed for intraoperative glycemic control.