Objective: Hypernatremia and hyperglycemia are highly prevalent in preterm infants during the first week after birth, and both can lead to hyperosmolarity and osmotic shifts. The objective is to determine whether hyperglycemia increases the risk of intraventricular hemorrhage (IVH) in hypernatremic preterm infants.
Study design: Single-center retrospective medical record review of 216 infants <1000 g birth weight and <29 weeks gestational age (admitted over a 9-year period) who had serum sodium levels and blood glucose levels monitored at least every 24 h and more frequently if indicated during the first 10 days after birth. Hyperglycemia was defined as persistently high blood glucose (usually >200 mg dl(-1)) treated with an insulin infusion. Hypernatremia was defined as a serum sodium level of ⩾150 mmol l(-1) on repeated measurements.
Results: Of the 216 infants studied, 76 (35%) developed hyperglycemia and 126 (58%) developed hypernatremia. IVH developed more frequently in infants with hyperglycemia (P=0.006, odds ratio (OR) 2.3, 95% confidence interval (CI) 1.3 to 4.1), in infants with hypernatremia (P=0.018, OR 2.0, 95% CI 1.2 to 3.5) and in infants with hypernatremia plus hyperglycemia (P=0.001, OR 3.2, 95% CI 1.6 to 6.4). Multivariate regression analysis confirmed the independent association of higher risk of IVH with the presence of hypernatremia plus hyperglycemia (P=0.015, OR 2.6, 95% CI 1.2 to 5.5) but not with hypernatremia or hyperglycemia alone.
Conclusion: Hyperglycemia increases the risk of IVH in hypernatremic preterm infants.