Neonatal Hypoglycemia Stan Jack, D.O. Saint Joseph Hospital Family Practice Residency

Neonatal Hypoglycemia - Significance Persistent or recurrent hypoglycemia can result in impaired neurologic development and intellectual functionPersistent or recurrent hypoglycemia can result in impaired neurologic development and intellectual function Other sequela include spasticity, ataxia, and seizure disorderOther sequela include spasticity, ataxia, and seizure disorder

Neonatal Hypoglycemia - Definition Plasma glucose <40 mg/dL on the first day of lifePlasma glucose <40 mg/dL on the first day of life Plasma glucose <40-50 mg/dL after 24 hours of agePlasma glucose <40-50 mg/dL after 24 hours of age Note: whole blood glucose ~15% lower than plasma glucose measurements Note: whole blood glucose ~15% lower than plasma glucose measurements

Neonatal Hypoglycemia - Pathogenesis Glucose in utero comes from motherGlucose in utero comes from mother After cord cut, glucose in newborn falls during first 2 hours, stabilizing by 4-6 hrs (transition period)After cord cut, glucose in newborn falls during first 2 hours, stabilizing by 4-6 hrs (transition period) Dependent on glycogen storage depletion and carbohydrate intakeDependent on glycogen storage depletion and carbohydrate intake

Neonatal Hypoglycemia - Causes Diminished glucose production (premature, IUGR)Diminished glucose production (premature, IUGR) Increased glucose utilization secondary to hyperinsulinism (infants of diabetic mothers, Beckwith-Weidmann, erythroblastosis, perinatal asphyxia)Increased glucose utilization secondary to hyperinsulinism (infants of diabetic mothers, Beckwith-Weidmann, erythroblastosis, perinatal asphyxia) Maternal tx with beta blockersMaternal tx with beta blockers SepsisSepsis

Neonatal Hypoglycemia - Causes (continued) PolycythemiaPolycythemia Metabolic disorders (inborn errors of carbohydrate / amino acid metabolism)Metabolic disorders (inborn errors of carbohydrate / amino acid metabolism) Endocrine disorders (low levels of cortisol, growth hormone, epinephrine, or glucagon)Endocrine disorders (low levels of cortisol, growth hormone, epinephrine, or glucagon) Heart failureHeart failure

Neonatal Hypoglycemia - Clinical Manifestations Frequently asymptomaticFrequently asymptomatic Jittery, tremulousJittery, tremulous Decreased toneDecreased tone Irritable or lethargic; seizuresIrritable or lethargic; seizures Apnea, bradycardia, cyanosis, tachypneaApnea, bradycardia, cyanosis, tachypnea Poor feedingPoor feeding

Neonatal Hypoglycemia - Screening Not routinely monitored unless at risk for hypoglycemia (next slide)Not routinely monitored unless at risk for hypoglycemia (next slide) If screening done, obtain sample before feedingsIf screening done, obtain sample before feedings

Neonatal Hypoglycemia - Risk Factors PrematurityPrematurity Small or large for gestational ageSmall or large for gestational age Infants of diabetic mothersInfants of diabetic mothers ICU infants (i.e. sepsis)ICU infants (i.e. sepsis) Infants of mothers treated with beta blockersInfants of mothers treated with beta blockers

Neonatal Hypoglycemia - Management If lower than 40 mg/dL, surveillance until feedings well established and glucose normalIf lower than 40 mg/dL, surveillance until feedings well established and glucose normal If asymptomatic and term, obtain blood sample and immediately offer breast or formula feeding (consider gavage); recheck minutes after feedingIf asymptomatic and term, obtain blood sample and immediately offer breast or formula feeding (consider gavage); recheck minutes after feeding

Neonatal Hypoglycemia - Management (continued) If symptomatic OR not tolerating enteral feeds OR plasma glucose <20-25 OR if persistently <40 even after feeds, start parenteral glucoseIf symptomatic OR not tolerating enteral feeds OR plasma glucose <20-25 OR if persistently <40 even after feeds, start parenteral glucose Bolus 200 mg/kg (2 ml/kg 10% dextrose in H2O) over 1 minute followed by glucose infusion of 8 mg/kg per minuteBolus 200 mg/kg (2 ml/kg 10% dextrose in H2O) over 1 minute followed by glucose infusion of 8 mg/kg per minute If requirements high (>12.5%) may need central venous catheterIf requirements high (>12.5%) may need central venous catheter

Neonatal Hypoglycemia - Summary Prolonged hypoglycemia may result in long-term morbidityProlonged hypoglycemia may result in long-term morbidity May be asymptomaticMay be asymptomatic Screening is based on risk factorsScreening is based on risk factors

Neonatal Hypoglycemia - Summary (continued) If asymptomatic and glucose is moderately low, begin with feeding and surveillanceIf asymptomatic and glucose is moderately low, begin with feeding and surveillance Symtomatic infants with very low glucose levels will need parenteral replacementSymtomatic infants with very low glucose levels will need parenteral replacement Do not hesitate to run things by your upper level, attending, or the neonatologistDo not hesitate to run things by your upper level, attending, or the neonatologist