Introduction: Blood glucose control in patients requiring intensive care remains a therapeutic challenge; however, recent advancements in glucose sensing technologies have sparked interest in the potential use of real-time continuous glucose monitoring in the subcutaneous compartment (rtCGM) also in the intensive care unit (ICU) setting. We performed a clinical trial assessing the accuracy and reliability of rtCGM in postoperative ICU patients after major abdominal surgery.

Methods: Patients undergoing pancreatic surgery, liver transplantation, pancreas (or pancreatic islets) and kidney transplantation were enrolled in the trial. Dexcom G6 (Dexcom, Inc., San Diego, USA) was used for rtCGM. Arterial blood glucose measured by the amperometric principle (ABL 800, Radiometer, Copenhagen, Denmark) served as reference and to calibrate the Dexcom G6 (every 6 hours on day 1, once daily day 2 and 3). Sensor accuracy was assessed by computing mean absolute relative difference (MARD), bias, modified Bland-Altman plot and surveillance error grid for paired samples of glucose values from CGM and ABL.

Results: Sixty-one patients after major abdominal surgery staying in ICU post-operatively were included into this analysis. Median monitoring length was 7 days with a 97.1 ± 6.5% proportion of active CGM use. Overall, 1566 paired glucose values measured with CGM and ABL were obtained. MARD for CGM compared with ABL-measured glucose was 9.7% with a bias of 0.9% and coefficient of variation of 14%. In the surveillance error grid analysis, 90.9% of pairs were in the 0 risk zone and 7.9% in the risk zone 1 (out of 7). Throughout the study 3 sensors needed to be replaced due to technical problems.

Conclusion: Our results show a clinically applicable accuracy and reliability of the Dexcom G6 continuous glucose monitoring system in postoperative ICU. This opens up new possibilities in intensifying ICU glucose control, lowering hypoglycaemia risk and reducing nursing staff workload.


B.Hagerf (voglová): None. M.Protus: None. L.Nemetova: None. M.Mraz: None. M.Haluzik: Advisory Panel; Novo Nordisk, Lilly Diabetes, Boehringer-Ingelheim, Research Support; Sanofi, Speaker's Bureau; Abbott, AstraZeneca. P.Girman: None. J.Franekova: None. V.Svirlochova: None. A.Jabor: None.


Charles University; Czech Ministry of Health; Institute for Clinical and Experimental Medicine (IKEM, IN00023001); National Institute for Research of Metabolic and Cardiovascular Diseases (EXCELES, LX22NPO5104)

Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered. More information is available at