Persistent pulmonary hypertension of the newborn treated with hyperventilation: clinical features and outcome.

Twenty-seven infants with severe persistent pulmonary hypertension of the newborn were seen in 33 months. Asphyxia with or without meconium aspiration was the cause in the majority of cases. Other causes were group B streptococcal sepsis and acute fetal blood loss. The mortality rate was 11%. Twenty-three of the 24 survivors were followed. Their age at follow-up ranged 12-37 months. The mean score for mental development was within the normal range while that for psychomotor development was 1 standard deviation below normal. Seven infants were judged to be at risk of attention deficit disorder. Predictor variables related to these outcomes were cardiotocography, meconium aspiration, first pH, highest PaCO2 after resuscitation and mother's education. All infants except one were perceived as normal by their parents.