Neonatal asphyxia. II. Neonatal mortality and long-term sequelae.

Neonatal asphyxia, defined in this study as delay of greater than 1 minute in onset of spontaneous respiration at birth, occurred in 1% of 13,221 live-born infants of birth weight greater than 500 gm between 1970 and 1971. Seventy-five (56%) of 133 asphyxiated infants survived the neonatal period. Survival was directly related to gestational age. The 65 survivors of asphyxia available for study were seen at a mean age of 4.8 years to determine the incidence and extent of neurologic and developmental abnormalities. Twelve children (18.5%) had severe impairment: nine had both neurologic and intellectual handicaps, two had neurologic impairment alone, and one had intellectual impairment alone. The incidence and severity of impairment were not related to gestational age. Postasphyctic seizures were associated with poor outcome.