Screening guidelines for newborns at risk for low blood glucose

Question 1

Who is at risk for neonatal hypoglycemia and what is the mechanism?

Answer 1

SGA (weight 90%ile), IDM

Due to impaired gluconeogenesis: due to excess insulin production, altered counter-regulatory hormone production or inadequate substrate.

(also at risk are those with other conditions like perinatal asphyxia, with symptoms/getting worked up for other reasons)

Question 2

When should neonates be screened for hypoglycemia?

Answer 2

@ 2 hours (after a feed) and q3-6hours a.c. feeds until end of at-risk period if BG maintained >2.6
SGA/prem: 12 hours
LGA/IDM: 36 hours (check 1-2x in second day of life)

Or, if symptomatic/unwell (““In approximate order of frequency there are jitteriness or tremors, apathy, episodes of cyanosis, convulsions, intermittent apneic spells or tachypnea, weak or high-pitched cry, limpness or lethargy, difficulty in feeding, and eye rolling. Episodes of sweating, sudden pallor, hypothermia, and cardiac arrest and failure also occur”)

Question 3

What is the threshold for treatment for neonatal hypoglycemia?

Answer 3

Although blood glucose levels as low as 1.8 mmol/L may be considered normal in healthy babies in the first few hours of life, adverse short- and long-term outcomes may result from levels lower than 2.6 mmol/L in those who are at-risk, particularly if the hypoglycemia is persistent or symptomatic.

At-risk babies who have
BG rpt BG 30min
(consult if >D12.5 TFI 100 required, to look for IEM or hyperinsulinism. Each incr, incr GIR by 25%)
(wean if stable BG x 12h)

if BG <2.6 mmol/L despite subsequent feeding should also be considered for IV.

Frequent breastfeeding on demand should be encouraged in at-risk babies.
Breastfeeding may be continued without risk of overhydration because the volume of colostrum is small. To avoid overhydration and hyponatremia in supplemented infants, oral and intravenous intake should not exceed 100 mL/kg/day without careful monitoring for dilutional hyponatremia.

There is both observational evidence and clinical consensus that sick, hypoglycemic infants, particularly those with neurological signs, should be treated immediately with an intravenous infusion of glucose.