Continuous Glucose Monitoring-Guided Insulin Infusion in Critically Ill Patients Promotes Safety, Improves Time Efficiency, and Enhances Provider Satisfaction

Endocr Pract. 2025 Sep;31(9):1143-1149. doi: 10.1016/j.eprac.2025.05.751. Epub 2025 Jun 23.

Abstract

Objective: Evaluate the integration of real-time CGM (rtCGM) into an insulin infusion computer calculator (IICC) to improve glycemic control, time efficiency, safety, and clinician workflow in the intensive care unit (ICU).

Methods: A retrospective analysis was conducted on 35 critically ill adult patients requiring insulin infusion in the surgical and medical ICUs. Dexcom G7 rtCGM values were integrated into an institution-developed IICC using an ongoing validation protocol, allowing for nonadjunctive CGM use. The accuracy of rtCGM was assessed by comparing matched CGM and point-of-care (POC) glucose values using mean absolute relative difference (MARD), surveillance error grid, and Parkes Error Grid analyses. CGM time-in-range metrics, clinician turnaround time for glucose monitoring, and nurse satisfaction were also evaluated.

Results: A total of 1291 matched glucose pairs were analyzed. The rtCGM system demonstrated a MARD of 12.5%, with 99.6% of the values falling within clinically acceptable error zones (A+B) on the Parkes Error Grid. Patients in the rtCGM-IICC protocol had mean glucose 141.9 mg/dL, with mean time in range (70-180 mg/dL) 82.8%, time above range (> 180 mg/dL) 14.5%, and time below range (< 70 mg/dL) 0.5%. Clinician time efficiency improved significantly, with POC testing requiring a mean turnaround time of nearly 5 minutes compared to 3-second CGM retrieval. All surveyed nurses (n = 20) reported rtCGM increased efficiency and improved safety and preferred rtCGM with POC over POC testing alone.

Conclusion: Integrating rtCGM with an IICC protocol in the ICU enhances glycemic control, improves workflow efficiency, and reduces clinician workload while maintaining high accuracy.

Keywords: clinician turnaround time (TAT); intensive care unit (ICU); mean absolute relative difference (MARD); real-time continuous glucose monitoring (rtCGM); surveillance error grid (SEG).

MeSH terms

  • Adult
  • Aged
  • Blood Glucose Self-Monitoring* / methods
  • Blood Glucose* / analysis
  • Continuous Glucose Monitoring
  • Critical Illness* / therapy
  • Female
  • Humans
  • Hypoglycemic Agents* / administration & dosage
  • Insulin Infusion Systems*
  • Insulin* / administration & dosage
  • Insulin* / therapeutic use
  • Intensive Care Units
  • Male
  • Middle Aged
  • Monitoring, Physiologic / methods
  • Retrospective Studies

Substances

  • Insulin
  • Blood Glucose
  • Hypoglycemic Agents