Performance of the Dexcom G6 Continuous Glucose Monitoring (CGM) system during cardiac surgery using hypothermic extracorporeal circulation

<p>  </p> <p><em>Background</em></p> <p>Continuous glucose monitoring (CGM) may be challenged by extreme conditions during cardiac surgery using hypothermic extracorporeal circulation (ECC).</p> <p><em>Research Design and Methods</em></p> <p>We evaluated the Dexcom G6 sensor in 16 subjects undergoing cardiac surgery with hypothermic ECC, of whom 11 received deep hypothermic circulatory arrest (DHCA). Arterial blood glucose, quantified by the Accu-Chek Inform II meter, served as reference. </p> <p><em>Results </em></p> <p>Intra-surgery mean absolute relative difference (MARD) of 256 paired CGM/reference values was 23.8%. MARD was 29.1% during ECC (154 pairs) and 41.6% immediately after DHCA (10 pairs), with a negative bias (signed relative difference: -13.7%, -26.6% and -41.6%). During surgery, 86.3% pairs were in Clarke error grid Zones A or B and 41.0% of sensor readings fulfilled the ISO 15197:2013 norm. Post-surgery, MARD was 15.0%.</p> <p><em>Conclusions</em></p> <p>Cardiac surgery using hypothermic ECC challenges the accuracy of the Dexcom G6 CGM although recovery appears to occur thereafter. </p>