Glycaemic control in type 2 diabetes mellitus patients undergoing major surgery: comparison of three subcutaneous insulin regimens.

Pre-operative glucose control with subcutaneous insulin in non-urgent situations is logical and well accepted. But the best regimen amongst the many available ones of insulin administration during peroperative period during major surgery is uncertain. We compared three subcutaneous insulin regimens for pre-operative glucose control in type 2 diabetes mellitus (T2DM) patients. One hundred and seventy-two T2DM patients hospitalised for major surgeries were enrolled in the study. Pre-operative glycaemic control was achieved with one of the following regimens: (1) Premix 30/70 insulin (R/N-0-R/N). (2) R + NPH; basal-bolus regular and NPH insulin (R-R-R/N). (3) R + G; basal-bolus regular and glargine insulin (R-R-R-G) [G: glargine insulin; N: neutral protamine hagedorn insulin; R: regular insulin]. Insulin doses were adjusted to achieve fasting and postmeal glucose values respectively <120 and <180 mg/dl. Intra-operative management included glucose insulin potassium solution. Postoperatively, patients were switched back to the same insulin regimen that they received pre-operatively. These regimens were compared for following parameters. (1) Time to achieve glycaemic target. (2) Total daily insulin dose. (3) Incidence of hypo- and severe hyperglycaemia. (4) Complications like renal failure, infection, etc. (5) in hospital mortality. R + G regimen was associated with lesser dose of insulin (29.53 +/- 9.83 versus 35.67 +/- 12.19 and 37.42 +/- 13.5 unit respectively for regimen 2 and 1, p < 0.005), lesser time to achieve glycaemic target (6.75 +/- 3.25 versus 7.37 +/- 7.47 and 8.23 +/- 6.04 days, p > 0.05), lower incidence of hypoglycaemia (10.53 versus 14.81 and 30.00%, p < 0.02) and severe hyperglycaemia (5.26 versus 29.63 and 8.33%, p < 0.005). Incidence of infection (10.53 versus 18.52 and 15.00%, p > 0.05), renal complications (10.53 versus 11.11 and 15.00%, p > 0.05) and mortality (5.26 versus 14.81 and 15.00%, p > 0.05) were lower with this regimen, but the difference was not statistically significant. Premix 30/70 and R + NPH regimens were comparable for most parameters but hypoglycaemia and severe hyperglycaemia were more frequent respectively with premix 30/70 and R + NPH regimens. In contrast to the popular perception about the risk of hypoglycaemia with long acting insulins, insulin analogue glargine was found to be better than NPH insulin in basal bolus regimens in achieving better glycaemic control with fewer incidence of hypoglycaemia.