Glucose is the major energy source for
fetus and neonate. The newborn brain depends upon glucose almost exclusively. Up to
90% of total glucose used is consumed by the brain. Alternate fuels (e.g., ketones,
lactate) are produced in very low quantities. The usual rate of glucose utilization is 4-8
mg/kg/min. Glucose regulatory mechanisms are sluggish at birth. Thus, the infant is
susceptible to hypoglycemia when glucose demands are increased or when exogenous
or endogenous glucose supply is limited. Severe or prolonged hypoglycemia may
result in long term neurologic damage.