Neonatal Hypoglycemia
NICU Night Team Curriculum
1
Objectives
• Define neonatal hypoglycemia
• Know the causes of neonatal
hypoglycemia
• Know signs and symptoms of
hypoglycemia
• Understand treatment
Case
39 wk F born by NSVD to a 22 y/o G1P0 mom
with diet controlled GDM A1. Mom’s blood
sugars throughout the pregnancy ranged from
120-160. Maternal serologies were negative,
pregnancy otherwise unremarkable.
APGARS were 8 and 9 at 1 and 5 minutes,
respectively. BW was 4,000 g.
Physical Examination
VS: T 36.5 P 148 RR 80 BP 55/38 mmHg
HC 34 cm (75%), Lt 50 cm (75%), BW 4,000 (>97%)
GA: Well appearing F, NAD, no cyanosis
HEENT: AF 2x2 cm, no cleft lip and palate
Heart: RR, no murmur
Lungs: Tachypneic breathing with even breath sounds
throughout, no retractions, no flaring
Abdomen: Soft ND, no hepatosplenomegaly
Genitalia: Normal female genitalia
Extremities: No deformities, MAEE
Labs
1 hour of life:
Hematocrit 56%
Dexi 30 mg%
Serum glucose 34 mg%
What is your primary
concern in this
patient?
Neonatal Hypoglycemia
Impaired glucose
metabolism
Serum blood glucose < 40 mg/dL
OR
Point of Care testing (accucheck, Dexi) <45
Why was a Dexi checked in
this patient?
She is at risk for developing hypoglycemia
Hypoglycemia
Definition: A plasma glucose of less than 40 mg/dl
Plasma glucose is higher than whole blood glucose by
15%
Physiology
Fetal Glucose Metabolism
• Fetus does not produce glucose
• Maternal glucose is the only source of
fetal glucose
• Baseline fetal blood glucose is 60-70%
of maternal serum glucose
Physiology
Glucose metabolism after birth
Cessation of maternal
glucose supply
Blood glucose Nadir
( ~1-2 hrs after birth)
Glucose Metabolism After Birth
Cessation of maternal
glucose supply
Surge in glucagon, catecholamine
Decrease insulin
Gluconeogenesis:
Hepatic glycogen, amino acid, fatty acid metabolism
Normal blood glucose
Etiology of neonatal
hypoglycemia
1. Increased utilization (e.g.: hyperinsulinism)
2. Decreased production/stores
3. Increased utilization and/or decreased
production
Increased Utilization
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Diabetic mother
Large for gestational age (LGA) infant
Erythroblastosis
Islet cells hyperplasia
Beckwith-Wiedemann syndrome
Insulin producing tumors
Maternal tocolytic therapy with B-sympathomimetric
agents
• Malposition of umbilical artery catheter
Decreased Production/Stores
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Prematurity
Intrauterine growth retardation(IUGR)
Inadequate caloric intake
Delayed onset of feeding
Increased utilization AND
Decreased production
• Perinatal stress eg. shock, sepsis, asphyxia
• Enchange transfusion
• Defect in carbohydrate metabolism eg. glycogen storage
disease
• Endocrne deficiency eg. adrenal insufficiency,
hypopituitarism
• Defect in amino acid metabolism
• Polycythemia
• Maternal therapy with B-blocker
When do you screen?
1. Symptoms that could be due to
hypoglycemia.
2. At risk infants.
What are signs and symptoms
of hypoglycemia?
Signs and Symptoms of
Hypoglycemia
Symptoms are NON-SPECIFIC
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Jitteriness
Apnea
Irritability
Grunting
Lethargy
Seizures
Who is at risk?
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Infants of diabetic mothers
Maternal use of B-adrenergic agonist/ antagonist
IUGR
LGA
Preterm
Polycythemia
Asphyxia
Sick infant
When is the ideal time to screen
high risk infants?
Screening
Blood glucose or point of care testing (POC)
should be done in high risk infants within
the first 1 to 2 hours after birth
Back to our case:
1.
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4.
Term LGA infant
IDM with poor blood glucose control
Tachypnea
Hypoglycemia
Why do you think she
developed hypoglycemia?
Hyperinsulinism
Pathophysiology : infants of diabetic mothers
How do you treat this
patient?
• Feeding?
• IV therapy?
• Medication?
Management – Oral Feeds
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Can be used in asymptomatic infants
Only formula (never administer glucose water!!)
Follow up blood glucose within 1 hour of feeding.
If the glucose level doesn’t rise, a more aggressive
therapy may be needed.
Management – IV therapy
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Indications:
Inability to tolerate oral feeding
Symptomatic infant
Lack of response with oral feeds
Glucose < 25 mg/dL, regardless of patient’s symptoms
Management – IV therapy
Urgent treatment
• Bolus 2 ml/kg of D10W
• Do not use 25% or 50% glucose !!
• Follow bolus with continuous dextrose fluid
Management – IV therapy
Continuing IV fluid
• Start infusion of glucose at a rate of 6-8 mg/kg/min
• Glucose infusion rate formula (GIR):
GIR
=
%IV fluid x rate(ml/hr)
6 x BW(kg)
Management – IV therapy
• Re-check serum glucose 20-30 min after bolus and
hourly until stable
– If glucose is normal and stable, feeding may be continued and
glucose infusion tapered
– If glucose can’t be maintained > 50 mg/dL, increase GIR by 1-2
mg/kg/hr
– If glucose can’t be maintained > 50 mg/dL, with a GIR 12
mg/kg/min, medication should be added.
Management – Medication
Persistent hypoglycemia despite a GIR > 12 mg/kg/min.
• Work up – Critical Labs:
– Serum cortisol, insulin, growth hormone when glucose is low and
prior to treatment
– DO NOT wait >5 minutes for labs prior to treating hypoglycemia
• Medication
– Hydrocortisone
– Glucagon
– Diazoxide
Hydrocortisone
• Dose: 10 mg/kg/day IV q 12 hrs
• Indication: Hypoglycemia despite GIR > 12 mg/kg/min
• Send hormone level before starting hydrocortisone!!!
Glucagon
• Dose: 0.025-0.3 mg/kg IM/IV
(maximum 1 mg)
• Should cause recovery of hypoglycemia
• May not work if
– Reduced glycogen stores
– Glycogen storage disease
Diazoxide
• Dose: 2-5 mg/kg/dose PO q 8 hrs.
• Indication: Infants who have persistent hyperinsulinemia
(e.g.. Nesidioblastosis)
Back to our case:
How would you treat our patient?
Remember, he was tachypneic
Urgent treatment:D10W 2 mL/kg IV bolus followed by
continuous IV fluid
Board Question
A term infant was born to a pre-ecclamptic mother. BW was
2,000 g (<10th%). Physical exam was normal.
Blood glucose at 2 hour of age was 30 mg/dL
What is your next step in management?
a. D10W bolus of 4 mL
b. D10W continuous IV infusion at 6.5 ml/hr
c. 20 mL of oral glucose water
d. 20 mL of infant formula
Board Question
A term infant was born to a pre-ecclamptic mother. BW was
2,000 g (<10th%). Physical exam was normal.
Blood glucose at 2 hour of age was 30 mg/dL
What is your next step management?
a. D10W bolus of 4 mL
b. D10W continuous IV infusion at 6.5 ml/hr
c. 20 mL of oral glucose water
d. 20 mL of infant formula
Reference
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Wilker RE. Hypoglycemia and hyperglycemia. In: Cloherty JP, Eichenwald EC, Stark AR, eds. Manual of Neonatal
care. 5th ed. Lippincott Williams & Wilkins; Philadelphia; 2008: 540-549
Cornblath M, Ichord R. Hypoglycemia in the neonate. Semin Perinatol 2000;24:136-149
Sperling MA, Menon RK. Differential diagnosis and management of neonatal hypoglycemia. Pediatr Clin North Am
2004;51:703-723