Impact of Hybrid Continuous Glucose Monitoring on Glycemic Control in a Medical Intensive Care Unit

Continuous glucose monitoring (CGM) offers real-time glucose data that may improve dysglycemia detection in critically ill patients; however, evidence supporting its clinical effectiveness in the intensive care unit (ICU) remains limited. The objective of this study was to evaluate whether a nurse-driven hybrid continuous glucose monitoring (CGM) plus point-of-care (POC) validation protocol improves glycemic outcomes compared with standard POC monitoring alone among medical ICU patients receiving continuous intravenous (IV) insulin.

In this single-center prospective intervention cohort study, 100 MICU patients receiving continuous IV insulin were monitored using a hybrid CGM+POC protocol and compared with 100 matched historical controls. The primary outcome was % time in glucose range (70-180 mg/dL) during continuous IV insulin therapy, calculated using POC values (at least every 4 hours) for between-group comparisons. Secondary outcomes included % time in additional glucose ranges, hyperglycemia (>250 and >400 mg/dL), and hypoglycemia (<70 and <54 mg/dL).

Compared with controls, CGM-managed patients achieved an increased time in range (76%±18 vs 64%±21; p<0.001) with persistent improvement after adjusting for confounders and marked reductions in severe hyperglycemia (>250 mg/dL: 6%±11 vs 17%±18; >300 mg/dL: 2.7±0.6% vs 11.3±1.4%; p<0.001 for both). Hypoglycemic events were infrequent and similar between groups. A total of 3,590 temporally matched CGM-POC pairs were available for analysis.

In this prospective MICU cohort, real-time hybrid CGM use improved glycemic control and reduced severe hyperglycemia without increasing hypoglycemia, supporting further evaluation of structured CGM integration in critical care practice.