Intermittent Versus Continuous Glucose Monitoring in Intensive Care Unit (ICONS-ICU)

Effect of Continuous Interstitial Glucose Monitoring on Glycaemic Targets and Clinical Outcomes in Critically Ill

Glucose control is an important part of supportive care for critically ill patients. Achieving optimal glucose control in such situations is challenging due to frequent fluctuations in blood glucose levels. These changes are often difficult to detect because the monitoring procedures are complex and require significant staff involvement, frequent blood draws, and consequent blood loss. Continuous glucose monitoring (CGM) is a simple and minimally invasive technique that has been approved and increasingly used by people with diabetes mellitus. However, its effectiveness in terms of glucose control management and accuracy in conditions with severe organ dysfunction has not been established.

The goal of this study is to assess the performance of CGM-guided glucose control in comparison to the standard glucose monitoring procedure. Additionally, the accuracy of CGM measurements under critical conditions will be evaluated against the standard of care.

Study Overview

• Status: Not yet recruiting
• Conditions: Critical Illness; Hyperglycaemia; Hypoglycaemia
• Intervention / Treatment: Device: Continuous glucose monitoring; Diagnostic test: Control Arm - standard of care

Detailed Description

This study will be an investigator-initiated, non-commercial, prospective, single-center, parallel-group, randomized controlled trial. Critically ill patients with hyperglycemia requiring intravenous insulin therapy will be randomly assigned to two groups: an intervention group that will receive intravenous insulin therapy aided by continuous glucose monitoring (CGM) measurements and a control group that will receive intravenous insulin therapy guided by arterial blood glucose measurements (RadiometerABL800). Patients will be enrolled within 48 hours after ICU admission. Intravenous insulin dosing will be adjusted according to the in-house glycaemic management protocol. After enrollment, patients will be monitored for maximal 10 days (duration of the sensor) or until stopping intravenous insulin therapy, ICU discharge or death, whichever occurs first, if these events happen before the sensor duration ends.

The primary outcome of the study will be the proportion of time spent within the target range of 7.8-10.0 mmol/L. Secondary outcomes will include mean glucose levels and other CGM metrics, daily vasoactive-inotropic score calculation, hospital length of stay, hospital-acquired infections, and acute renal failure.

Additionally, an accuracy analysis in extreme clinical conditions (pH < 7.20, post-resuscitation, ECMO support, severe haemodynamic instability, hypoxia) will be performed by comparing CGM measurements measured by DexcomG7 with arterial blood glucose measurements (RadiometerABL800) from the electronic health record. Satisfaction of health-care personnel will be evaluated. Sensor-related complications will be monitored.

• Study Type: Interventional
• Enrollment (Estimated): 200
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Milica Lukic, MD; Phone Number: +386 1 522 7283; Email: milica.lukic@kclj.si
• Study Contact Backup: Name: Alenka Golicnik, MD PhD; Phone Number: +386 1 522 9516; Email: alenka.golicnik@kclj.si

Study Locations

• Slovenia
  • Ljubljana, Slovenia
    • University Medical Center Ljubljana
    • Contact: Peter Radsel, MD, PhD; Phone Number: + 386 1 522 9513; Email: peter.radsel@kclj.si
    • Principal Investigator: Milica Lukic, MD
    • Sub-Investigator: Alenka Golicnik, MD, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• age ≥ 18 years
• admission to the level 3 ICU
• two consecutive blood glucose measurements > 10.0 mmol/L
• intravenous insulin therapy

Exclusion Criteria:

• expected ICU stay < 48 hours
• pregnancy
• type 1 diabetes
• diabetic emergencies (DKA, DAHS)
• severe skin disease
• severe neutropenia (< 0.5 × 10^9/L)
• severe coagulopathy (thrombocytes < 20 × 10^9/L)
• manufacturer-defined conditions (hydroxyurea use, acetaminophen more than 4 g daily)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: CGM monitoring; DexcomG7 continuous glucose monitor	Device: Continuous glucose monitoring; Intravenous insulin therapy will be guided by interstitial glucose measurements using DexcomG7 continuous glucose monitor. Confirmatory blood glucose tests will be performed daily. In extreme clinical conditions (post-resuscitation, pH < 7.20, severe hypoxia, severe haemodynamic compromise), confirmatory blood tests will be performed in 2 hour intervals until clinical improvement.
Active Comparator: Standard of care; Radiometer ABL800 blood glucose measurement	Diagnostic test: Control Arm - standard of care; Intravenous insulin dosing will be guided according to blood glucose measurements using RadiometerABL800 (standard of care). DexcomG7 continuous glucose monitor will be applied in blinded mode for interstitial glucose monitoring for later CGM metrics and comparison analysis.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time in range 7,8 - 10,0 mmol/l	Percentage of time within recommended glucose range	from the enrollment until completion of the continuous glucose monitoring (up to 10 days)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean glucose levels		from the enrollment until completion of the continuous glucose monitoring (up to 10 days)
Glycemic variability	assessed by the coefficient of variation (CV) and standard glucose variation	from the enrollment until completion of the continuous glucose monitoring (up to 10 days)
Vasopressor inotropic score	estimated amount of vasopressor support, daily calculated with the Vasoactive Inotropic Score (VIS): minimum 0 - 5 points (low doses), maximum > 45 points (highest doses)	from the enrollment until completion of the continuous glucose monitoring (up to 10 days)
Hospital acquired infections	pneumonia, bloodstream infections, urinary infections	from the enrollment until hospital discharge, approximately 30 days
Acute renal failure	defined by AKIN (acute kidney injury) classification	from the enrollment until hospital discharge, approximately 30 days

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Hospital mortality	death during hospitalization	from the enrollment and before hospital discharge, approximately 30 days
Time above range (level 1 and 2)	percentage of time above 10,1 - 13,9 mmol/l (level 1) and above 13,9 mmol/l (level 2)	from the enrollment until completion of the continuous glucose monitoring (up to 10 days)
Time below range (level 1 and 2)	percentage of time below 3,0 - 3,8 mmol/l (level 1) and below 3,0 mmol/l (level 2)	from the enrollment until completion of the continuous glucose monitoring (up to 10 days)

Collaborators and Investigators

• Sponsor: University Medical Centre Ljubljana
• Investigators: Study Chair: Milica Lukic, MD, University Medical Centre Ljubljana

Study record dates

Study Major Dates

• Study Start (Estimated): July 1, 2025
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): December 1, 2026

Study Registration Dates

• First Submitted: June 23, 2025
• First Submitted That Met QC Criteria: July 19, 2025
• First Posted (Actual): July 28, 2025

Study Record Updates

• Last Update Posted (Actual): July 28, 2025
• Last Update Submitted That Met QC Criteria: July 19, 2025
• Last Verified: July 1, 2025

More Information

Terms related to this study

• Keywords: continuous glucose monitoring; icu
• Additional Relevant MeSH Terms: Pathologic Processes; Disease Attributes; Metabolic Diseases; Glucose Metabolism Disorders; Hypoglycemia; Critical Illness; Hyperglycemia
• Other Study ID Numbers: ICONS-ICU

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: All IPD that underlie results in a publication will be shared.
• IPD Sharing Time Frame: Start date: 1 month after publication End date: no end date
• IPD Sharing Access Criteria: IPD and supporting information will be stored and shared in the Repository of the University of Ljubljana, Slovenia. Access will be provided on request by the Repository.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes