A POPULATION STUDY - MORTALITY AND MORBIDITY AFTER AVAILABILITY OF SURFACTANT THERAPY

Objective: To assess the impact of recent changes in neonatal intensive care o Design: Prospective cohort study. Setting: Six neonatal intensive care units in Wisconsin and Iowa. Participants: All very-low-birth-weight neonates who were admitted to the neonatal intensive care units the year before the availability of exogenous surfactant (n=333), during the investigational new drug protocol for synthetic surfactant (Exosurf) (n=347), and after the release of synthetic surfactant (n=356) (designated as periods 1, 2, and 3, respectively). Interventions: None. Main Results: The percentage of neonates receiving exogenous surfactant in the three periods was 3%, 37%, and 56%, and the percentage receiving antenatal steroids was 12%, 17%, and 27% (P=.0001 for increase in both modalities). The percentage of neonates dying in the three periods was 23%, 14%, and 19% (P=.05 for downward trend). The percentage of neonates with intraventricular hemorrhage decreased in the subgroup weighing between 700 and 1350 g (35%, 28%, and 24%) (P=.04) and increased in the subgroup weighing below 700 g (8%, 41%, and 45%) (P=.03). The percentage of neonates with bronchopulmonary dysplasia increased from 21% to 36% between periods 1 and 2 (P=.003) and decreased to 27% (P=.04) in period 3. Antenatal steroid use was strongly associated with the decrease in intraventricular hemorrhage (odds ratio, 0.35) and mortality risk (odds ratio, 0.20). Conclusions: Several developments in care have contributed to changes in mortality risk, incidence of intraventricular hemorrhage, and the severity of respiratory disease in very-low-birth-weight infants.