Chapter 79. Hypoglycemia and Metabolic Emergencies in Infants and Children

Hypoglycemia in children may be due to inadequate oral intake, excess insulin, low levels of hyperglycemic hormones (cortisol), inborn errors of metabolism, or systemic infection. Prompt recognition and treatment of hypoglycemia is essential to avoid potentially severe and permanent neurologic injury and bedside glucose testing should be considered absolutely essential in any infant or child with altered mental status.

Clinical Features

Neonates and infants with hypoglycemia typically present with altered mental status and nonspecific symptoms such as poor feeding, an abnormal or high-pitched cry, temperature instability, and irritability or lethargy. Hypoglycemic children may manifest symptoms related to adrenergic hormone release including tachycardia, diaphoresis, tremors, anxiety, irritability, and tachypnea. Severe hypoglycemia may result in apnea or seizures. Hypoglycemia often accompanies critical illness (sepsis) and the features of that illness may dominate the clinical picture, thereby masking the signs of hypoglycemia.

Diagnosis and Differential

Hypoglycemia is defined as a plasma glucose concentration less than 45 milligrams/dL in symptomatic children and less than 35 milligrams/dL in asymptomatic neonates. Bedside glucose testing is the most important diagnostic test in any neonate or infant who is critically ill or has altered mental status. Urine testing for ketones is important as ketonuria is associated with ketotic hypoglycemia, adrenal insufficiency and other inborn errors of metabolism. Absent urine ketones are associated with hyperinsulinemic states such as nesidioblastosis, infants of a diabetic mother, as well as disorders of fatty acid oxidation and mitochondria.

Emergency Department Care and Disposition

1. For neonates administer 5 mL/kg of 10% dextrose IV/IO/PO/NG. Treat infants with the same dose of 10% dextrose, or 2 mL/kg of 25% dextrose IV/IO/PO/NG. Give older children 2 mL/kg of 25% dextrose IV/IO/PO/NG.

2. Administer maintenance dextrose for persistent hypoglycemia using 10% dextrose at 1.5 times maintenance.

3. When intravenous access is not immediately available, consider glucagon 0.03 milligram/kilogram IM.

4. When standard therapy fails, give hydrocortisone 25 milligrams IV for neonates and infants, 50 milligrams for toddlers and smaller school aged children and 100 milligrams for everyone else. Steroids should be given early in patients with hypopituitarism and adrenal insufficiency.

Inborn errors of metabolism are challenging childhood disorders representing a broad spectrum of diseases with nonspecific signs and symptoms. Delay in accurate diagnosis and treatment can lead to significant morbidity and mortality. Despite the myriad etiologies, the principles of initial ED diagnosis and management are relatively simple. The sudden acute deterioration of a ...