Hypoglycemia---blood sugar (blood glucose) less than 30 mg/dl (milligrams per deciliter) in the first 24 hours of life---occurs most frequently in newborn infants of diabetic mothers, babies who are small for gestational age (SGA) and premature babies. Cold, stress, infection and a number of diseases can also cause hypoglycemia.
Hypoglycemia can cause seizures, coma or brain damage unless treated promptly with oral or intravenous glucose. Babies at risk are monitored closely after birth for signs of hypoglycemia and with blood tests, since babies who become hypoglycemic may be asymptomatic, according to the Merck Manual online medical library.
Central Nervous System Signs
Low levels of glucose in the blood cause disturbances in the central nervous system (CNS). Common CNS side effects of neonatal hypoglycemia include jitteriness, tremors and seizures, according to Merck. Hypoglycemic newborns may have an exaggerated Moro (startle) reflex or a high-pitched cry, the Stanford Medical School states, and may have temperature instability. Some hypoglycemic newborns will be sweaty.
According to Merck, jitteriness, tremors and sweating are caused by adrenaline release, a response to hypoglycemia. Seizures and low body temperature are other responses directly related to low glucose, according to Merck. Glucose should be given to treat all hypoglycemic symptoms, either in formula or breast milk if the baby is able to feed, or intravenously in severe cases.
Cardiopulmonary Signs
Hypoglycemic newborns may breathe rapidly, grunt when breathing or have bradypneic or apneic episodes, where breathing slows or stops altogether. Respiratory distress is a neuroglycemic response, according to Merck, as is cyanosis, or turning blue. Newborns with hypoglycemia may have a fast heart rate or a very slow heart rate, according to Merck. Babies who can't be fed orally due to respiratory or cardiac distress should be given intravenous glucose.
Lethargy
Newborns with hypoglycemia may feed poorly and seem lethargic, with floppy muscle tone. They may go into a coma. If glucose isn't given, death can result.
