Glargine insulin: an alternative to regular insulin for glycemic control in critically ill patients

Introduction

The objective of this study was to determine the efficacy and safety of subcutaneous (s.c.) once-daily (OD) glargine insulin, a long-acting insulin, in comparison with a s.c. regular insulin, based on a protocolized sliding scale regimen for achieving glycemic control in patients admitted to the ICU.

Methods

One hundred patients admitted to the ICU with an admission capillary blood glucose (CBG) >150 mg/dl (8.3 mmol/l) were involved in this prospective, randomized study. Patients with age <18 years, pregnancy, shock, requiring continuous intravenous insulin infusion, renal failure were excluded. Patients were randomly assigned to receive either s.c. glargine insulin 10 U (CBG ≤ 9.9 mmol/l) or 18 U (CBG ≥ 10.1 mmol/l) s.c. OD (Group G, n = 50), or s.c. regular insulin based on a 6-hourly sliding scale (Group R, n = 50). CBGs were recorded at 6-hour intervals up to 96 hours or until ICU discharge, whichever was earlier. The target CBG in both groups was <150 mg/dl (8.3 mmol/l). Patients in group G received rescue doses of regular insulin, as required. Demographic characteristics, mean and median CBG, and episodes of hypoglycemia were studied.

Results

Demographic profiles were comparable between the two groups. There was no significant difference in mean CBG in both groups (Group G 152.1 mg/dl (8.4 mmol/l), Group R 149.9 mg/dl (8.3 mmol/l), P = 0.66). Median CBGs were comparable at 6-hourly time points in both the groups except at 0 and 6 hours in the glargine arm (CBG at 0 and 6 hours, Group G 10.0 mmol/l and 9.9 mmol/l, Group R 9.4 mmol/l and 8.3 mmol/l, P = 0.04 and 0.02, respectively) (Figure 1). There were three episodes of hypoglycemia in Group G and one in Group R, which were corrected.

Figure 1

Median capillary blood glucose (CBG) at different time points.

Conclusion

OD s.c. glargine insulin is a safe and effective alternative to regular insulin for glycemic control in critically ill patients.