Randomized Evaluation of Glycemic Control in the Medical Intensive Care Unit Using Real-Time Continuous Glucose Monitoring (REGIMEN Trial)

Background and Objective: Hyperglycemia occurs commonly in patients admitted to medical intensive care units (MICUs). Whether real-time (RT) continuous glucose monitoring (CGM) improves glycemic control and variability and reduces hypoglycemia in severely ill MICU patients with an Acute Physiology and Chronic Health Evaluation II (APACHE-II) score of 20 has not been studied. Subjects and Methods: Thirty-five patients (6610 years of age; APACHE-II score, 286) were randomly assigned to RT-CGM (n=16) using the GlucoDay((R))S (A. Menarini Diagnostics, Florence, Italy) device or to blinded CGM. Insulin was infused using a modified Yale protocol targeting a blood glucose level between 80 and 120mg/dL. Outcome measures were percentage of time in normoglycemia (80-110mg/dL) and in hypoglycemia (<60mg/dL), glycemic variability (SD, coefficient of variation, mean amplitude of glucose excursions, and mean of daily differences), and CGM accuracy (error grid analyses, Bland-Altman bias plot, and mean absolute relative deviation). Results: During 96h of monitoring, glycemia reached target (80-110mg/dL) in 37 +/- 15%, was between 70 and 180mg/dL in 91 +/- 10%, and <60mg/dL in 2 +/- 2% of the time. In the RT-CGM group glycemia averaged 119 +/- 17mg/dL versus 122 +/- 11mg/dL in the control group. Parameters of glucose variability and percentages of time at target glycemia and in hypoglycemia were similar between groups. GlucoDayS values and arterial glycemia correlated well, with 98.6% of data falling in Zones A and B of the error grid analysis. Mean absolute relative devation was 11.2%. Conclusions: RT-CGM did not ameliorate glucose control or variability; neither did it reduce the number of hypoglycemic events, but our insulin infusion protocol led to overall good glucose control without a significant hypoglycemia risk, making further improvement difficult.