Background. We previously demonstrated improved survival and early outcomes
in a pilot trial of 2 doses of intravenous dexamethasone for infants with
surfactant-treated respiratory distress syndrome.(1) A multicenter, randomi
zed, double-blind trial was undertaken to confirm these results.
Methods. Infants <30 weeks' gestation were eligible if they had respiratory
distress syndrome, required mechanical ventilation at 12 to 18 hours of ag
e, and had received at least 1 dose of exogenous surfactant. Infants were e
xcluded if sepsis or pneumonia was suspected or if congenital heart disease
or chromosomal abnormalities were present. A total of 384 infants were enr
olled-189 randomized to dexamethasone (.5mg/kg birth weight at 12-18 hours
of age and a second dose 12 hours later) and 195 to an equal volume of sali
ne placebo.
Results. No differences were found in the dexamethasone versus placebo grou
ps, respectively, regarding the primary outcomes of survival (79% vs 83%),
survival without oxygen at 36 weeks' corrected gestational age (CGA; both 5
9%), and survival without oxygen at 36 weeks' CGA and without late glucocor
ticoid therapy (46% vs 44%). No significant differences between the groups
in estimates from Kaplan-Meier survival analyses were found for median days
on oxygen (50 vs 56 days), ventilation (20 vs 27 days), days to regain bir
th weight (15.5 vs 14 days), or length of stay (LOS; 88 vs 89 days). Infant
s given early dexamethasone were less likely to receive later glucocorticoi
d therapy for bronchopulmonary dysplasia during their hospitalization (27%
vs 35%). No clinically significant side effects were noted in the dexametha
sone group, although there were transient elevations in blood glucose and b
lood pressure followed by a return to baseline by study day 10. Among infan
ts who died (40 vs 33), there were no differences in the median days on oxy
gen, ventilation, nor LOS. However, in survivors (149 vs 162), the followin
g were observed: median days on oxygen 37 versus 45 days, ventilation 14 ve
rsus 19 days, and LOS 79 versus 81 days, for the dexamethasone versus place
bo groups, respectively.
Conclusions. This dose of early intravenous dexamethasone did not reduce th
e requirement for oxygen at 36 weeks' CGA and survival was not improved. Ho
wever, early dexamethasone reduced the use of later prolonged dexamethasone
therapy, and among survivors, reduced the median days on oxygen and ventil
ation. We conclude that this course of early dexamethasone probably represe
nts a near minimum dose for instituting a prophylactic regimen against bron
chopulmonary dysplasia.