Comparative study between insulin bolus regimen and glucose insulin infusion regimen on effectiveness of intraoperative blood glucose control in patients with type 2 diabetes mellitus undergoing non-cardiac surgery

Background: The surgical rates are comparatively greater among diabetic patients. Surgery, a period of stress, mandates fasting and anti-diabetic medications are skipped on the morning of the procedure. High blood glucose levels in the peri-operative period can lead to ischaemia, infection, acute kidney injury and electrolyte disturbances. Hence, control of blood glucose levels during the peri-operative period becomes important and there are various regimens described. We compared two of the existing regimens, intravenous insulin bolus and glucose insulin infusion regimen, for their effectiveness of intraoperative blood glucose control. Method: In this randomized, prospective controlled study, 120 patients were enrolled with 60 patients in bolus group and 60 in infusion group. Capillary blood glucose was measured every hour during the intra-operative period. The primary outcome measure was proportion of patients in the target glucose levels between 100 mg/dL and 180 mg/dL and proportion of intra-operative surgery time (in minutes) during which patient was in the target range. Secondary outcome measure was serum potassium levels pre-operatively and postoperatively. Results: The proportion of patients in the target range in the bolus group was 39 out of 60 as compared to 31 out of 60 in the infusion group (P=0.13). Also, proportion of intraoperative surgery time (in minutes) during which patient was in the target glycaemic range was 41.57% in bolus group when compared to 27.22% in the infusion group (P < 0.05). No hypoglycaemic episodes were seen in any of the patients in the two groups. Conclusion: As compared with infusion regimen, bolus regimen provides better glycaemic control measured in terms of target blood glucose levels and duration for which the patient remained in the target range.