Efficacy of Continuous Glucose Monitoring in Neonates With Hypoglycemia

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.

Inclusion criteria:

- Age 0-60 days old

- Late-preterm and term infants (babies born more than 33 weeks and 6 days after the
start of the pregnancy)

- History of low blood sugars (hypoglycemia): two episodes of hypoglycemia more than 1
hour apart (low blood sugar will be defined by age: for those less than 48 hours old a
low blood sugar is considered less than 50mg/dL and for those older than 48 hours old
less than 70mg/dL)

Exclusion Criteria:

- Infants with skin disease such that placement of a glucose sensor under the skin would
be difficult to secure

- Infants expected to remain in NICU less than 24 hours

- Infants on a hypothermic protocol

- Infants enrolled in a competing clinical trial

- Family/team have decided to limit or redirect from aggressive NICU technological
support

- infants who are wards of the state