RANDOMIZED TRIAL OF ANTENATAL DEXAMETHASONE IN SURFACTANT-TREATED INFANTS DELIVERED BEFORE 30 WEEKS GESTATION

Objective: To determine if an additive effect exists between antenatal corticosteroid administration and postnatal surfactant therapy in the prevention of respiratory distress syndrome (RDS) in preterm infants. Methods: A randomized, double-blind trial was conducted from April 19 90 to June 1994, in which dexamethasone (5 mg every 12 hours for a tot al of four doses) or saline was given to women at risk for delivery at 24-29 weeks' gestation. At birth, prophylactic surfactant was adminis tered to all study infants. Main outcome measures were RDS occurrence and severity. Secondary clinical end points included bronchopulmonary dysplasia, pneumothorax, patent ductus arteriosus, necrotizing enteroc olitis, retinopathy, intraventricular hemorrhage, and death. Results: Seventy-five of the 124 randomized subjects delivered 96 infants withi n the studied gestational age range (dexamethasone, n = 54; placebo, n = 42). Similar maternal demographics and obstetric complications were noted between study groups. A greater proportion of infants were deli vered from multi-fetal gestations in the dexamethasone cohort (26 of 5 4 versus 12 of 42 newborns; P = .05). There were no significant differ ences in the occurrence or severity of RDS between the dexamethasone a nd placebo infants (none or mild, 67 versus 67%; moderate, 24 versus 2 6%; severe, 9 versus 7%, respectively), or differences in any of the s econdary clinical outcomes. The study size was sufficient to exclude a 50% reduction in RDS incidence as a consequence of dexamethasone expo sure. An analysis restricted to singletons (dexamethasone, n = 28; pla cebo, n = 30) revealed similar overall occurrence of intraventricular hemorrhage (12 of 28 versus ten of 30; P = .63), but significantly few er grade 3 and 4 intraventricular hemorrhages in dexamethasone-exposed neonates (two of 12 versus six of ten; P = .048). Conclusion: Antenat al dexamethasone does not appear to decrease the incidence or severity of RDS in surfactant-treated infants delivered at 24-29 weeks' gestat ion, but may be associated with reduced severity of intraventricular h emorrhages in surfactant-treated singletons in this gestational age ra nge.