Comparison of the effect of insulin glargine and regular insulin on perioperative glycemic control in patients with type 2 diabetes mellitus under insulin treatment during vitrectomy surgery under general anesthesia: A randomized clinical trial study

Background: Perioperative glycemic control is an important factor in the clinical management of a patient with diabetes mellitus under surgery. Poorly controlled long-term hyperglycemia not only predisposes individuals to systemic complications of diabetes mellitus and cardiovascular morbidity but also increases the risk of anesthesia and weakens the outcome of the surgery. Given the importance of the issue and the limited studies on glucose control using insulin glargine during surgery, we aimed to investigate the effects of glargine on glucose control in patients with diabetes mellitus during vitrectomy surgery. Methods: This randomized, double-blind trial was conducted in two groups of 35 patients with diabetes mellitus under treatment with insulin. In the control group, the patients received regular insulin based on the blood glucose and the sliding scale, and in the intervention group, they received insulin glargine (0.3 unit/kg) before surgery. From the start of the operation up to 3 hours of the surgery blood glucose of the patients was measured every 45 minutes and once 6 hours after the operation, and if needed, the regular insulin was injected. Data were analyzed using SPSS 16. Frequency, percentage, mean, and standard deviation (SD) were used to describe the data. To compare the quantitative variables, the independent t-test or U-Mann-Whitney test was used. For comparison of the qualitative variables, Chi-square test or Fischer's exact test and repeated measure ANOVA was employed. The significance level (P-value) was considered as p<0.05. Results: Use of insulin glargine was associated with significantly lower blood glucose levels compared to regular insulin at 90-minutes (p=0.004), 135 minutes (p=0.001), and 6 hours after the operation (p=0.005). Conclusion: Glycemic control using glargine compared to regular insulin has a better performance with less need for surplus insulin dose administration during surgery.