(471) Evaluation of NPH Insulin Dosing Interval on Glycemic Control for Critically Ill Patients

Tuesday, February 25, 2025

12:30pm – 1:30pm Eastern Time

Location: Connections Central - RST 12

First Author(s)

Delaney Adams, PharmD

University of Tennessee Health Science Center, USA

Co-Author(s)

Brandon Conaway, PharmD

Pharmacist
Memphis VA Medical Center, United States
JF

Julie Farrar, PharmD, BCCCP

University of Tennessee College of Pharmacy
Memphis, Tennessee, USA
SB

Saskya Byerly, MD, MS

Assistant Professor of Trauma/Surgical Critical Care
n/a
Memphis, Tennessee, United States
DF

Dina M. Filiberto, MD, MS

Associate Professor of Trauma/Surgical Critical Care, Fellowship Program Director
University of Tennessee Health Science Center
Memphis, Tennessee, United States
PF

Peter E. Fischer, MD, MS, NREMT-P, FACS

Associate Professor of Trauma/Surgical Critical Care, Trauma Medical Director
University of Tennessee Health Science Center, United States
RD

Roland Dickerson, PharmD, BCNSP, FCCP, FASHP, FCCM, FASPEN

Professor of Clinical Pharmacy and Translational Science
University of Tennessee College of Pharmacy
Memphis, Tennessee, United States

Introduction: Reduction in hyperglycemia is associated with improved outcomes for critically ill patients. The intent of this study is to ascertain whether there is an advantage of administering subcutaneous Neutral Protamine Hagedorn (NPH) insulin every 8 hours (Q8h) versus every 12 hours (Q12h) for hyperglycemic patients receiving continuous enteral nutrition (EN).

Methods: We retrospectively examined glycemic control metrics for hyperglycemic critically ill trauma patients who received EN and NPH Q8h or Q12h with supplemental intravenous sliding scale (SSI) regular human insulin (RHI) every 3 to 4 hours based on a standardized SSI dosing algorithm. Patients received at least 4 days of NPH therapy and were evaluated for 7 days while receiving NPH. Patients were assigned to Q8h or Q12h at the discretion of the Nutrition Support Service. Target blood glucose (BG) range was 70 to 179 mg/dL. Time in target BG range and glycemic variability was assessed via the difference in daily max-min BG or coefficient of variation (CV). Level 1 hypoglycemia was defined as a BG < 70 and > 53 mg/dL. The t-test or Wilcoxon signed rank test were used to compare continuous variables between groups.

Results: Thirty-four patients (15 given Q8h NPH and 19 given Q12h NPH) were evaluated. There was no difference in average BG (168 ± 18 vs 166 ± 17 mg/dL, P=0.803), time in target BG range (15 ± 5 vs 16 ± 6 h, P=0.419), BG max-min (74 ± 22 vs 70 ± 25 mg/dL, P=0.694), or CV (14 ± 3 vs 14 ± 4%, P=0.848). Level 1 hypoglycemia occurred in 2 patients from each group (P=1.000). However, patients given Q8h NPH required more NPH (62 ± 30 vs 26 ± 15 units/d, P=0.026) and total insulin (115 ± 52 vs 58 ± 33 units/d, P=0.004) despite similar carbohydrate intakes (115 ± 35 vs 108 ± 37 g/d, P=0.584). The Q8h group exhibited a higher maximum BG (293 ± 82 vs 248 ± 97 mg/dL, P=0.046), required a RHI infusion (73% vs 32%, P=0.038) and a higher insulin dose (115 ± 52 vs 58 ± 33 units/d, P=0.004) prior to NPH.

Conclusions: Q8h NPH performed as effectively as Q12h NPH dosing despite its use in a more challenging glycemic control population. Further research is required to ascertain if similar glycemic control metrics occur when both dosing strategies are used in a similar challenging population.