AKT · Child health/Neonatal & surgicallow yield

Neonatal hypoglycaemia

Low blood glucose in the newborn (transitional, or from at-risk groups)

Overview

Low blood glucose in the newborn — common transiently in the first hours, but persistent/symptomatic hypoglycaemia risks neurological injury. At-risk groups: infants of DIABETIC mothers (hyperinsulinism), small/large-for-gestational-age, preterm, unwell/septic, hypothermic. Managed by feeding and, if low/symptomatic, buccal dextrose gel or IV glucose; persistent hypoglycaemia needs investigation (hyperinsulinism, metabolic, endocrine).

Recognise

Often asymptomatic; symptomatic signs are non-specific: jitteriness, poor feeding, lethargy, hypotonia, apnoea, seizures
At-risk: infant of a diabetic mother (hyperinsulinaemic), SGA/LGA, preterm, sepsis, hypothermia, perinatal stress
Persistent/recurrent hypoglycaemia → investigate (congenital hyperinsulinism, metabolic, endocrine)

Red flags

Symptomatic or very low glucose → IV glucose (and treat the cause)
Persistent hypoglycaemia → endocrine/metabolic work-up (hyperinsulinism, hypopituitarism, inborn errors)

Differentials & how to tell them apart

Transitional hypoglycaemiamild, early, resolves with feeding

Congenital hyperinsulinismpersistent, high glucose requirement, low ketones — needs specific treatment

Sepsis/HIE/metabolichypoglycaemia can accompany these — treat the cause

Investigations

Blood glucose monitoring in at-risk infants; if persistent, a 'hypoglycaemia screen' (insulin, cortisol, growth hormone, ketones, lactate, metabolic tests) taken at the time of hypoglycaemia.

Management

Feed ± buccal dextrose gel; IV glucose if symptomatic/very low; treat the cause

1Monitor glucose in at-risk infants; support feeding and use buccal dextrose gel for borderline-low asymptomatic babies. Symptomatic or very low glucose → IV glucose.Gate: Symptomatic hypoglycaemia needs prompt IV glucose (neurological risk); persistent/recurrent hypoglycaemia requires a hypoglycaemia screen TAKEN AT THE TIME of the low glucose (to catch hyperinsulinism/endocrine/metabolic causes)
2Treat the underlying cause (diazoxide for hyperinsulinism, etc.); wean glucose as feeding establishes; specialist work-up for persistent cases.

Feeding ± buccal dextrose gel — first-line for asymptomatic at-risk infants

IV glucose (dextrose) — for symptomatic/very low glucose

Treat the cause — e.g. diazoxide for hyperinsulinism (specialist)

Key points

At-risk neonate (diabetic mother/SGA/preterm/unwell) + low glucose = neonatal hypoglycaemia → feed/gel or IV glucose. Persistent hypoglycaemia → screen AT the time for hyperinsulinism/endocrine/metabolic causes.

Monitor & prognosis

Glucose; feeding; cause if persistent.

Good if treated; neurological risk if missed.

Source: BAPM; RCPCH