(382) Improved Glycemic Control With Eight-Hour Versus 12-Hour NPH Insulin for Critically Ill Patients

Introduction: Reduction in hyperglycemia has been associated with improved clinical outcomes for critically ill patients. Neutral Protamine Hagedorn (NPH) insulin has been successfully used for glycemic control for hyperglycemic critically ill patients who required enteral nutrition. However, NPH insulin causes peak and nadir concentrations. The purpose of this study is to assess and compare glycemic control in critically ill patients who received NPH every 12 hours versus 8 hours.

Methods: This retrospective case series was conducted at a level 1 regional trauma center. Patients > 18 years who received continuous enteral nutrition and were transitioned from every 12 hours to 8 hours NPH insulin were included in the analysis. Patients were given supplemental intravenous regular human insulin (RHI) every 3 to 4 hours in addition to NPH insulin based on a standardized institutional sliding scale dosing algorithm (SS RHI). Primary efficacy outcome was the average number of hours per day in target blood glucose (BG) range (70-179 mg/dL). Primary safety outcome was the number of Level 1 (BG < 70 mg/dL) and Level 2 hypoglycemic episodes (BG < 54 mg/dL). The Fischer exact test and paired t-tests were used to compare data from each NPH dosing group.

Results: A total of 11 patients were included. Mean age was 54 ± 14 years and mean ICU length of stay was 30 ± 12 days. Most patients had type 2 diabetes mellitus with an average near-admission hemoglobin A1c of 7.7 ± 1.8 %. Average hours/day in the target BG range while receiving NPH every 12h was 13.5 ± 7.3 h/d compared to 18.4 ± 4.7 h/d while receiving NPH every 8h (P=0.016). Total insulin intake (NPH + SS RHI) was similar between Q12h and Q8h dosing groups (79 ± 27 vs 83 ± 23 units/d, respectively, P=0.606). Mean carbohydrate intake from the enteral feeding was similar between Q12h and Q8h dosing groups (93 ± 31 vs. 97 ± 30 g/d, respectively; P=0.511). No hypoglycemic episodes occurred while receiving NPH every 12h. A total of 4 Level 1 hypoglycemic events occurred in 3 patients while receiving NPH every 8h (P=0.230). There were no Level 2 hypoglycemic events.

Conclusions: NPH given every 8h provided more time in the target BG range and improved glycemic control compared to NPH every 12h for critically ill trauma patients.