Background: Clinical trials have proven that surfactant therapy is effective in improving the immediate need for respiratory support and the clinical outcome of premature newborns (Soll 1992, Jobe 1993). Trials have studied a wide variety of surfactant preparations used either to prevent (prophylactic or delivery room administration) or treat (selective or rescue administration) respiratory distress syndrome. Using either treatment strategy, significant reductions in the incidence of pneumothorax, as well as significant improvement in survival, have been noted. It is unclear if there is an advantage to choosing either the prophylactic or selective approach to treatment
Objectives: To compare the effect of prophylactic surfactant administration to surfactant treatment of established respiratory distress syndrome in premature infants.
Search strategy: Searches were made of the Oxford Database of Perinatal Trials, Medline (MeSH terms: pulmonary surfactant; limits: age groups, newborn infants; publication type, clinical trials), previous reviews including cross-references, abstracts, conference and symposia proceedings, expert informants, and journal handsearching in the English language.
Selection criteria: Randomized controlled trials that compared the effects of prophylactic surfactant administration to surfactant treatment of established respiratory distress syndrome in premature infants were included in the analysis.
Data collection and analysis: Data regarding clinical outcomes including the incidence of pneumothorax, pulmonary interstitial emphysema, patent ductus arteriosus, necrotizing enterocolitis, intraventricular hemorrhage (any grade and severe intraventricular hemorrhage), bronchopulmonary dysplasia, mortality, bronchopulmonary dysplasia or death, and retinopathy of prematurity were excerpted from the reports of the clinical trials by the reviewers. Data analysis was done in accordance with the standards of the Cochrane Neonatal Review Group.
Main results: Eight studies were identified that met inclusion criteria. The majority of included studies noted an initial improvement in the respiratory status and a decrease in the incidence of respiratory distress syndrome in infants who received prophylactic surfactant. The meta-analysis supports a decrease in the incidence of pneumothorax, a decrease in the incidence of pulmonary interstitial emphysema, a decrease in the incidence of mortality and a decrease in the incidence of bronchopulmonary dysplasia or death associated with prophylactic administration of surfactant. No significant untoward effects of prophylactic surfactant administration are noted. In a secondary analysis of infants less than 30 weeks gestation, the meta-analysis suggests a significant decrease in the risk of neonatal mortality and the risk of mortality or bronchopulmonary dysplasia.
Reviewer's conclusions: Prophylactic surfactant administration to infants judged to be at risk of developing respiratory distress syndrome (infants less than 30-32 weeks gestation), compared to selective use of surfactant in infants with established RDS, has been demonstrated to improve clinical outcome. Infants who receive prophylactic surfactant have a decreased risk of pneumothorax, a decreased risk of pulmonary interstitial emphysema and a decreased risk of mortality. However, it remains unclear exactly which criteria should be used to judge "at risk" infants who would require prophylactic surfactant administration.