The Performance of Dexcom G6 Glucose Monitoring in Critically Ill Patients

This is an investigator-initiated, prospective, observational accuracy-study. The aim of the study is to test the feasibility, safety, and accuracy of a subcutaneous continuous glucose monitoring system (the Dexcom G6 glucose monitoring system) in critically ill patients. A total of 40 adult patients admitted to the intensive care unit requiring intravenous insulin infusion to maintain blood glucose within target range will be enrolled. Subcutaneous glucose readings will be compared with routine arterial blood glucose measurements to determine accuracy.

Study Overview

• Status: Recruiting
• Conditions: Blood Glucose; Critical Care; Humans
• Intervention / Treatment: Device: subcutaneous continuous glucose sensor

Detailed Description

The primary endpoint of the study is the mean absolute relative difference (MARD) in percent between CGM and arterial glucose values. Calculations show that 40 patients are required for a 95% confidence interval for the mean to have a range of ±1.7%, meaning that MARD can be estimated with high precision. Calculations of confidence intervals were done using normal approximation, assuming an SD of 5.5 percentage units.

The following variables will be collected from the electronic medical record (Take Care), from the ICU-specific patient data management system (Clinisoft) and/or from the handheld Dexcom G6 monitor:

Patient-related variables:

• Age, sex, height and weight
• Comorbidities (including diabetes status)
• Chronic medications

Clinical variables:

• Date and time of ICU admission and discharge
• Reason for ICU admission
• Admission source (e.g. emergency department, other hospital, ward)
• Illness severity scores (e.g. SAPS [Simplified Acute Physiology Score], SOFA [Sequential Organ Failure Assessment])
• Hemodynamic variables (e.g. heart rate, blood pressure)
• Blood gas results (including blood glucose concentration)
• Other routine laboratory results (e.g. serum creatinine, serum albumin, haematocrit)
• ICU mortality

Treatment variables:

• Insulin doses (including continuous intravenous infusion rates, intravenous and subcutaneous insulin boluses) and times
• Doses and administration time for other medications given in the ICU (e.g. Vasopressors, paracetamol)

Continuous Glucose Monitoring (CGM)-related variables:

• Date and time of sensor insertion
• Sensor insertion site
• Number and duration of disconnection episodes
• Reason for disconnection
• Date and time of sensor calibrations
• Sensor glucose values with date and time stamps
• Date and time of sensor removal
• Reason for sensor removal
• Complications at sensor insertion site (redness, swelling, infection, bruising)

Exact date and time of sensor insertion will be manually recorded in a case report form at the bedside. Every time an arterial blood gas is obtained, the arterial blood glucose value and the corresponding CGM glucose value will be manually recorded along with date and time in the case report form. At the end of the study period, after removing the CGM sensor, CGM-data will be downloaded from the handheld Dexcom G6 monitor.

• Study Type: Interventional
• Enrollment (Anticipated): 40
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Johan Mårtensson, MD, PhD; Phone Number: +46 (0)8-12394821; Email: johan.martensson@regionstockholm.se
• Study Contact Backup: Name: Ola Friman, RN; Phone Number: +46 (0)8-51775830; Email: ola.friman@regionstockholm.se

Study Locations

• Sweden
  • Stockholm, Sweden, 17176
    • Recruiting
    • Karolinska University Hospital
    • Contact: Johan Mårtensson, MD, PhD; Phone Number: +46 (0)8-12394821; Email: johan.martensson@regionstockholm.se
    • Contact: Ola Friman, RN; Phone Number: +46 (0)8-51775830; Email: ola.friman@regionstockholm.se

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age ≥18 years
• Admitted to ICU at the Karolinska University Hospital Solna
• Indwelling arterial catheter in situ or expected to be inserted in the next 2 hours
• Six hours or less since intravenous insulin infusion was commenced or intravenous insulin infusion expected to commence within the next 2 hours
• Vasopressor infusion ongoing or expected to commence within the next 2 hours
• Mechanical ventilation ongoing or expected to commence within the next 2 hours
• Patient expected to stay in the ICU until the day after tomorrow

Exclusion Criteria:

• Pregnancy
• Unable to get consent from patient or next-of-kin
• Patients in whom death is considered imminent (within 24 hours)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Critically ill adults requiring insulin; Patients admitted to the intensive care unit requiring insulin infusion to maintain blood glucose within target range	Device: subcutaneous continuous glucose sensor; Dexcom G6 continuous glucose monitoring system

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean absolute relative difference (MARD)	MARD in percent between subcutaneous sensor glucose values and arterial blood glucose values	From date of sensor insertion until date of ICU discharge, date of removal of the arterial line, or date of death, whichever came first, assessed up to 10 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean absolute difference (MAD)	MAD between subcutaneous sensor glucose values and arterial blood glucose values	From date of sensor insertion until date of ICU discharge, date of removal of the arterial line, or date of death, whichever came first, assessed up to 10 days
Numerical accuracy according to ISO criteria	Numerical accuracy between subcutaneous sensor glucose values and arterial blood glucose values determined according to the International Organization for Standardization (ISO) criteria from 2013 (ISO 15197:2013)	From date of sensor insertion until date of ICU discharge, date of removal of the arterial line, or date of death, whichever came first, assessed up to 10 days
Numerical accuracy according to CLSI standard	Numerical accuracy between subcutaneous sensor glucose values and arterial blood glucose values determined according to the Clinical and Laboratory Standards Institute (CLSI) Point of Care Testing 12-A3 (POCT12-A3) standard	From date of sensor insertion until date of ICU discharge, date of removal of the arterial line, or date of death, whichever came first, assessed up to 10 days
Clinical accuracy determined by Clarke error grid analysis	Clinical accuracy between subcutaneous sensor glucose values and arterial blood glucose values determined by Clarke error grid analysis	From date of sensor insertion until date of ICU discharge, date of removal of the arterial line, or date of death, whichever came first, assessed up to 10 days
Clinical accuracy determined by surveillance error grid analysis	Clinical accuracy between subcutaneous sensor glucose values and arterial blood glucose values determined by surveillance error grid analysis	From date of sensor insertion until date of ICU discharge, date of removal of the arterial line, or date of death, whichever came first, assessed up to 10 days
Correlation	Correlation between arterial blood glucose levels and subcutaneous sensor glucose values	From date of sensor insertion until date of ICU discharge, date of removal of the arterial line, or date of death, whichever came first, assessed up to 10 days

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of interrupted sensor readings (Feasibility outcome)	Number of interrupted sensor readings	From date of sensor insertion until date of ICU discharge, date of removal of the arterial line, or date of death, whichever came first, assessed up to 10 days
Duration of interrupted sensor readings (Feasibility outcome)	Duration of interrupted sensor readings (hours)	From date of sensor insertion until date of ICU discharge, date of removal of the arterial line, or date of death, whichever came first, assessed up to 10 days
Adverse events (safety and tolerability)	Local reactions (e.g. allergic skin reactions, bruising) related to sensor insertion/sensor adhesives	From date of sensor insertion until date of ICU discharge, date of removal of the arterial line, or date of death, whichever came first, assessed up to 10 days

Collaborators and Investigators

• Sponsor: Region Stockholm
• Collaborators: DexCom, Inc.
• Investigators: Principal Investigator: Johan Mårtensson, MD, PhD, Karolinska University Hospital

Publications and helpful links

General Publications

• Matuleviciene V, Joseph JI, Andelin M, Hirsch IB, Attvall S, Pivodic A, Dahlqvist S, Klonoff D, Haraldsson B, Lind M. A clinical trial of the accuracy and treatment experience of the Dexcom G4 sensor (Dexcom G4 system) and Enlite sensor (guardian REAL-time system) tested simultaneously in ambulatory patients with type 1 diabetes. Diabetes Technol Ther. 2014 Nov;16(11):759-67. doi: 10.1089/dia.2014.0238. Epub 2014 Sep 18.

Study record dates

Study Major Dates

• Study Start (Actual): November 19, 2021
• Primary Completion (Anticipated): June 30, 2023
• Study Completion (Anticipated): June 30, 2023

Study Registration Dates

• First Submitted: January 26, 2022
• First Submitted That Met QC Criteria: February 15, 2022
• First Posted (Actual): February 25, 2022

Study Record Updates

• Last Update Posted (Actual): April 5, 2023
• Last Update Submitted That Met QC Criteria: April 4, 2023
• Last Verified: April 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Disease Attributes; Critical Illness
• Other Study ID Numbers: K 2021-5279; FoUI-960993 (Other Grant/Funding Number: Region Stockholm (ALF project))

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

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