Frequency of Neonatal Hyperglycemia at Assuit University Children Hospital

Hyperglycemia has become an important risk factor for mortality and morbidity in the neonatal period, especially with increased survival rates of very low birth weight neonates.

Neonatal hyperglycemia is usually defined as serum glucose greater than 150 mg/dl (8.3 mmol/L) or whole blood glucose greater than 125 mg/dl (6.9 mmol/L) irrespective of gestational or postmenstrual age. Usually, the safe target for a neonate's serum glucose level is 70 to 150 mg/dl. The cut off for safe target is based on the renal glucose threshold of preterm neonates.

Hyperglycemia is more common in preterm infants than term infants as it occurs in one-third of preterm and small gestational age (SGA) infants and is generally noted during the first week of life. Usually, the acute hyperglycemia resolves over two to three days in most neonates but can last up to ten days. Hyperglycemia is less common than hypoglycemia among neonates but is associated with increased mortality and morbidity among neonates. Neonatal hyperglycemia is inversely related to birth weight and gestational age.

Glucose is an essential source of energy for the fetus and neonate. The brain growth of the fetus exclusively depends upon glucose. In the early postnatal period, glucose homeostasis occurs via glycogenolysis and gluconeogenesis. The critical regulatory mechanisms of glucose homeostasis are sluggish in the initial days, particularly among preterm neonates. The mechanisms of neonatal hyperglycemia are multifactorial. The risk of hyperglycemia increases with the severity of the accompanying illness. The most common cause is high exogenous glucose infusion rates (GIR) in preterm infants who are already at risk for hyperglycemia due to the following reasons,

• decreased ability to suppress endogenous glucose production,
• decreased insulin response to glucose, and
• limited glycogen and fat stores. Hyperglycemia in the neonatal period develops as a result of other multiple risk factors including.