We aim to evaluate the utility of continuous glucose monitors (CGMs) in improving the diagnosis and management of neonatal hypoglycemia in infants admitted to the neonatal intensive care unit (NICU). Specifically, we hope to assess whether the use of CGMs in this population reduces the number and severity of hypoglycemic events, reduces the time to diagnosis of the etiology of hypoglycemia and/or reduces the time taken to achieve stable euglycemia on a sustainable feeding regimen. We plan to perform a prospective pilot and feasibility study comparing the clinical course and outcomes of newborns with hypoglycemia admitted to the NICU who are actively monitored with CGMs versus those who receive routine care. Eligible infants will be late preterm and term infants admitted to the Boston Children's Hospital who have had two documented hypoglycemic episodes during their current admission. Families will be approached for consent shortly after diagnosis of recurrent hypoglycemia. As all of these infants will be undergoing periodic blood glucose monitoring as part of their routine care, enrollment in this study will involve minimal additional interventions, including CGM placement, which involves placement of a small subcutaneous needle sensor, and the possibility of drawing additional blood glucose samples if hypoglycemia is detected by CGM. All enrolled infants will be placed on a CGM monitor and then randomized to either the "CGM Protocol" or "Standard of Care" group. Those on the CGM Protocol will have a fully accessible CGM that will be analyzed for blood glucose trends and will alarm for any blood glucose level approaching hypoglycemic threshold (eg. BG \<70 mg/dL). Those in the "Standard of Care" group will have a CGM in place, but values will not be available to the clinical team except if severe hypoglycemia is recorded (eg. BG \<40 mg/dL). Whenever the CGM alarms or there is a concerning blood glucose trend as measured by the CGM, the nurse will be asked to check a blood glucose value. All clinical management decisions will be made by the clinical team based on confirmed blood glucose values. In the control group, the only change to current management is the potential performance of additional blood glucose checks that may be prompted by CGM alarms for severe hypoglycemia. The CGM will remain in place until the infant is no longer being monitored for glycemic stability or the infant is discharged. We will record all blood glucose levels, laboratory data related to investigation of the underlying cause of hypoglycemia, all intravenous and enteral sources of glucose, and uses of other therapeutic interventions such as diazoxide and carnitine replacement. We will also compare blood glucose data with information from the CGM monitors to assess accuracy. We will then compare severity and frequency of hypoglycemia, as well as times to diagnosis and euglycemia between the "CGM" and "Standard of Care" groups.
