What is the management of hypoglycemia (low blood sugar) in neonates?

Management of Neonatal Hypoglycemia

Neonatal hypoglycemia requires prompt identification and treatment in at-risk infants, with intervention thresholds of <2.6 mmol/L (47 mg/dL) for symptomatic infants and operational thresholds based on risk factors to prevent neurological injury. 1

Risk Factors for Neonatal Hypoglycemia

The highest-scoring clinical practice guideline identifies these risk factors requiring screening:

• Infants of diabetic mothers (IDM)
• Preterm infants (<37 weeks gestation)
• Small for gestational age (SGA) infants (<10th percentile)
• Low birth weight (<2500g)
• Large for gestational age (LGA) infants (>90th percentile)
• Birth weight >4500g
• Post-term infants (>42 weeks gestation) 1

Approximately 26.3% of all newborns meet criteria for hypoglycemia screening based on these risk factors 1.

Diagnosis and Monitoring

Blood Glucose Measurement

• Blood gas analyzers with glucose modules provide the most accurate and rapid results for neonatal glucose measurement 1
• Point-of-care glucometers may be inaccurate in neonates and should be confirmed with laboratory testing 1
• Continuous glucose monitoring may identify undetected hypoglycemic episodes but remains investigational 1

Operational Thresholds for Intervention

Intervention is recommended at these blood glucose thresholds:

• <1 mmol/L (18 mg/dL): single measurement requires immediate intervention
• <2 mmol/L (36 mg/dL): persistent low value on repeated measurement
• <2.5 mmol/L (45 mg/dL): single measurement with abnormal clinical signs 1

Treatment Algorithm

First-Line Treatment

1. Oral dextrose gel is recommended as first-line treatment for asymptomatic hypoglycemia 2, 3

   • Apply to buccal mucosa
   • Follow with feeding (preferably breastfeeding)
   • Recheck glucose after 15 minutes

2. Feeding

   • Early and frequent breastfeeding or formula feeding
   • Feeding should be initiated as soon as possible after birth in at-risk infants

Second-Line Treatment (if oral treatment fails)

1. Intravenous glucose
   • Intravenous glucose infusion should be considered as soon as practical after resuscitation 1
   • Begin with continuous infusion rather than bolus to avoid rapid glucose fluctuations 1
   • Avoid rapid rises in glucose levels as they may be associated with poorer neurodevelopmental outcomes 1

For Severe or Symptomatic Hypoglycemia

1. Glucagon
   • For infants >25kg or ≥6 years: 1mg subcutaneously or intramuscularly
   • For infants <25kg or <6 years: 0.5mg subcutaneously or intramuscularly 4
   • Recheck glucose after 15 minutes; may repeat dose if no response

Monitoring During Treatment

• Recheck blood glucose 15-30 minutes after intervention
• Continue monitoring until stable glucose levels are maintained
• For IV glucose therapy, gradually wean while monitoring glucose levels

Prevention Strategies

• Early feeding within first hour of life for at-risk infants
• Skin-to-skin contact to promote thermoregulation
• Avoid prolonged fasting periods in at-risk infants
• Consider prophylactic oral dextrose gel in high-risk infants 2

Long-Term Implications

Severe and prolonged hypoglycemia is associated with:

• Neurologic injury and long-term neurodevelopmental sequelae 1
• Impaired visual-motor processing and executive functioning in early childhood 1
• Reductions in literacy and numeracy skills in mid-childhood 1

Even mild, transient hypoglycemia may affect:

• Visual motor function
• Executive function
• Academic achievement in later childhood 2

Special Considerations

• Preterm infants are uniquely vulnerable due to limited glycogen/fat stores and inability to generate new glucose through gluconeogenesis 5
• Infants of diabetic mothers are at high risk due to hyperinsulinism from maternal hyperglycemia 1
• Asymptomatic hypoglycemia requires vigilant monitoring as it may still cause neurological injury 2

Pitfalls to Avoid

1. Delayed recognition - Most hypoglycemic infants show no clinical signs; rely on screening in at-risk populations 3
2. Overreliance on point-of-care glucometers - These may be inaccurate in neonates 1
3. Rapid correction with IV bolus - Can cause harmful glucose fluctuations 1
4. Inadequate follow-up - Continued monitoring is essential until stable glucose levels are maintained
5. Failure to investigate persistent hypoglycemia - May indicate underlying metabolic or endocrine disorders 6

Neonatal hypoglycemia management requires balancing the risks of untreated hypoglycemia against the potential disruption of breastfeeding and parent-infant bonding from excessive interventions. The goal is to prevent brain injury while supporting normal neonatal transition and feeding establishment.