Comparison of Glycemic Control between Continuous Regular Insulin Infusion and Single-dose Subcutaneous Insulin Glargine Injection in Medical Critically Ill Patients

Background and Aims: This study aimed to compare glycemic control between continuous intravenous regular insulin infusion and single-dose subcutaneous insulin glargine injection in medical critically ill patients. Subjects and Methods: A prospective noninferiority study was conducted in medical critically ill patients who developed hyperglycemia and required regular insulin infusion by the Intensive Care Unit glycemic control protocol. The eligible patients were switched from the daily regular insulin requirement to single-dose subcutaneous insulin glargine injection by a 100% conversion dose. Arterial blood glucose was checked every 2 h for 24 h. Success cases were blood glucose levels of 80-200 mg/dL during the study period. The mean time-averaged area under the curves (AUCs) of blood glucose levels between the two types of insulin were compared by t-test. Results: Of 20 cases, 14 cases (70%) were successful. The mean time-averaged AUCs of blood glucose levels between the two types of insulin were not significantly different (155.91 +/- 27.54 mg/dL vs. 151.70 +/- 17.07 mg/dL, P = 0.56) and less than the predefined noninferior margin. No severe hypoglycemic cases were detected during the study period. Conclusions: Single-dose subcutaneous insulin glargine injection was feasibly applied for glycemic control in medical critically ill patients. The glycemic control in the critically ill patients by a single dose of subcutaneous insulin glargine was comparable to standard intravenous regular insulin infusion. A conversion dose of 100% of the daily requirement of regular insulin is suggested.