Trisha Branan, PharmD, BCCCP
Clinical Associate Professor and Assistant Department Head
University of Georgia College of Pharmacy
Jefferson, Georgia
Disclosure information not submitted.
Kendall Huntt, Pharm.D. Candidate
Pharmacy Student
University of Georgia College of Pharmacy, United States
Disclosure information not submitted.
Thomas Tuggle, Pharm.D. Candidate
Pharmacy Student
University of Georgia College of Pharmacy, United States
Disclosure information not submitted.
Susan Smith, BCCCP, BCPS, PharmD
Clinical Associate Professor
University of Georgia
Athens, Georgia
Disclosure information not submitted.
Title: Incidence of Hyperglycemia with Subcutaneous Insulin vs Insulin Infusions in Critically Ill Patients
Introduction/Hypothesis: Although guidelines recommend the use of insulin infusion protocols for the management of hyperglycemia in critically ill (ICU) patients, many institutions utilize subcutaneous insulin regimens despite little evidence for efficacy and safety. The goal of this study is to compare the incidence of hyperglycemia in ICU patients managed with subcutaneous insulin versus insulin infusion protocol.
Methods: This was an observational, retrospective, historical control study. A random sample of 100 adult ICU patients treated with subcutaneous insulin regimens in 2020 were included. Baseline demographics and blood glucose (BG) values over the first four ICU days were collected. The primary outcome was the percentage of BG values >180 mg/dL. Secondary outcomes included the percentage of BG values 70-180 mg/dL, average overall BG, and frequency of hypoglycemia. Data were compared to a previously published historical control group that received continuous insulin infusion via protocol using the Chi-squared test or two-sided t-test for categorical and continuous variables, respectively, with alpha < 0.05 to determine significance.
Results: There were 1622 BG values from 100 patients in the subcutaneous group and 8332 BG values from 171 patients in the infusion group. Demographics were similar between groups with mostly older, Caucasian males. The incidence of hyperglycemia (BG >180 mg/dL) was higher in the subcutaneous insulin group compared to the insulin infusion group (63% vs 36%, p< 0.001). The subcutaneous group had fewer BG readings in the target range (51% vs 63%, p< 0.001) and a higher average overall BG (187.9 mg/dL vs 172.4 mg/dL, p=0.002). There were no significant differences in the rate of hypoglycemia between the groups with BG values of 41-69 mg/dL (0.6% vs 1.1%, p=0.087) or ≤40 mg/dL (0.3% vs 0.1%, p=0.074).
Conclusions: ICU patients treated with subcutaneous insulin regimens had significantly higher rates of hyperglycemia and less optimal glycemic control compared with protocolized insulin infusions. Additionally, patients treated with subcutaneous insulin were three times more likely to experience a severe hypoglycemic event. Glycemic variability has been associated with nosocomial infections and increased mortality; however, patient outcomes were not evaluated in this study.