Factors, other than surfactant, in the etiology of respiratory distress syndrome.

A review of 23 recently published series demonstrates that many infants with immature or intermediate surfactant patterns do not develop respiratory distress syndrome. This suggests that factors other than surfactant deficiency must be present. It is suggested that surfactant deficiency is a predisposing factor, but aspiration of amniotic fluid and its contents at the time of delivery is the most important precipitating cause.