Hypoglycemia

Question 1

Transitional hypoglycemia definition

Answer 1

=< 2.6 in first 72 hours post-birth

Question 2

Persistent hypoglycemia definition

Answer 2

=< 3.3 after 72 hours post-birth

Question 3

Infants at risk of hypoglycemia

Answer 3

• SGA: wt < 10th %ile
• IUGR
• < 37 weeks GA
• LGA: wt > 90th %ile
  
  • unclear if nonsyndromic LGA non IDM babies truly at risk for hypoglycemia
• IDMs
• maternal labetalol
• late preterm antenatal steroids
• perinatal asphyxia
• metabolic conditions (CPT-1 deficiency in Inuit infants)
• Syndromes associated with hypoglycemia (BWS)

Question 4

What is whipple’s triad?

Answer 4

signs and symptoms of hypoglycemia, low serum glucose level, resolution of signs and symptoms with the provision of glucose

Question 5

How to define hypoglycemia?

Answer 5

1. Using clinical manifestations
   * clinical signs in order of frequency: jitteriness or tremors, cyanotic episodes, convulsions, intermittent apneic spells or tachypnea, weak or high-pitched crying, limpness or lethargy, difficulties feeding, eye-rolling
   
   • others: sweating, sudden pallor, hypothermia, cardiac arrest and failure
     * must document hypoglycemia and confirm if signs disappear with glucose
2. Using normative range
   * BG fall right after birth (as low as 1.8 at 1 hr) —> rise to >2.0 and maintained x 72 hr
   * 12-14% newborns have BG <2.6 in first 72 hours
3. Using presence or absence of acute normal physiological, metabolic, and endocrine change
   * rise in ketones, GH, cortisol, catecholamines
   * low insulin
4. Using the presence or absence of sequelae
   * BG <2.6 associated with short and long term neurological/neuroimaging changes
   * some showed: long-term sequelae with low BG in first 72 hours, no harm from transient hypoglycemia, long-term sequelae with recurrent hypoglycemia

Question 6

most common cause of hypoglycemia in infants

Answer 6

impairment of gluconeogenesis

* etiologies: excess insulin, altered counter-regulary hormone production, inadequate substrate supply

Question 7

How to screen at-risk infants for hypoglycemia?

Answer 7

• No routine screening for appropriate-for-gestational age infants at term
• Screen at 2 hours and q3-6 hrs after that
• IDM (and LGA) infants: minimum screen for 12 hours (hypoglycemia early)
• SGA & preterm: minimumscreen for 24 hours (hypoglycemia as late as 2nd day)
  
  • must be feeding and BG >=2.6 before stopping
  • screen 1-2x DOL 2
• Symptomatic: screen right away

Question 8

When to do a critical sample?

Answer 8

Bg =< 2.8 at > 72 hours of life

Question 9

What testing needs to be done for BG before discharge of infant?

Answer 9

• Neonates monitored for hypoglycemia need 5-6 hr fast and maintain BG >= 3.3 prior to DC

Question 10

What should a normal critical sample show during hypoglycemia?

Answer 10

• should have low insulin, high ketones, counter-reg hormones (GH & cortisol)

Question 11

What is the max concentration of dextrose that can be given by PIV?

Answer 11

D20

Question 12

What is the max TFI that can be given in the transitional period?

Answer 12

• Max TFI 100 mL/kg/day —> if up to this much, monitor serum lytes

Question 13

How do you give dextrose gel?

Answer 13

• 0.5 mL/kg of 40% dextrose gel = 200 mg/kg glucose (equivalent to 2 mL/kg D10 bolus)