The correlation of seizures in newborn infants with significant acidosis at birth with umbilical artery cord gas values

Abstract

OBJECTIVE: To correlate umbilical blood gas variables with neonatal seizures in neonates with significant acidosis at birth (pH ≤ 7.1). METHODS: We reviewed the maternal and neonatal charts of 238 patients at a gestational age of 32 weeks or more with cord gases done at delivery and an umbilical artery pH of 7.1 or less. All infants transferred to the neonatal intensive care unit were studied, and those with neonatal seizures secondary to hypoxic ischemic encephalopathy were identified. We used the perinatal outcome of early neonatal seizures secondary to hypoxic ischemic encephalopathy to divide the patients into two groups. The relationship between the umbilical artery parameters of pH, base deficit, partial oxygen pressure (pO 2), partial carbon dioxide pressure (pCO 2), and the neonatal outcome of seizures were determined with Student t tests and multiple logistic regression analysis. RESULTS: Umbilical artery base deficit, pO 2, and pCO 2 were significantly elevated in newborns who had seizures, whereas cord pH was decreased. Using multiple regression analysis the variable neonatal seizure was predicted only by low umbilical artery pH. A pH of less than 7 was more sensitive (73.8%) than a base excess of −16 (52.5%) in predicting the development of neonatal seizures. CONCLUSION: Our data suggest that severe fetal acidemia identified by a pH less than 7.0 was the most important umbilical blood gas variable for predicting early onset of neonatal seizures.