Continuous glucose monitoring during intravenous insulin infusion treatment: Assessing accuracy to enable future clinical utility.

AIMS

Continuous glucose monitoring (CGM) during intravenous insulin infusions (IVII) could reduce blood glucose (BG) testing burden in hospital, however CGM accuracy concerns exist. We aimed to assess CGM accuracy during IVII.

METHODS

This multi-centre observational study included adults with type 1 diabetes (T1D) who required IVII treatment during hospital admission whilst wearing their own CGM devices (Abbott FreeStyle Libre 2, Medtronic Guardian 3, Dexcom G6). IVII dose adjustments were performed based upon standard of care BG measures. Accuracy was assessed according to mean absolute relative difference (MARD) and Consensus error grid (CEG) analysis, using time-matched (±5 minutes) pairs of CGM glucose and reference BG (point-of-care [POC], blood gas [GAS]) obtained during IVII.

RESULTS

In total, 736 time-matched glucose pairs were obtained from 56 hospital admissions (52% with diabetic ketoacidosis; 32% requiring intensive care). Median IVII duration was 16 hours (IQR 7.2-28). Overall MARD was 12.5% (11.9% for CGM-POC pairs; 14.1% for CGM-GAS pairs). In CEG analysis, 99.0% of glucose pairs were within zones A/B. Based on local hospital IVII dose titration protocols for non-intensive care wards, if CGM measures had been used instead of POC, dose adjustments would have been the same in 77% of instances.

CONCLUSIONS

This real-world study of adults with T1D demonstrated high concordance of CGM measures with BG during IVII. The accuracy of CGM during IVII might enable its greater clinical utility when treating inpatients receiving IVII. More inpatient studies are required to validate the use of CGM during IVII.