Background: This section is under preparation and will be included in the next issue.
Objectives: To assess the effect of prophylactic intratracheal administration of natural surfactant extract in preterm newborns at risk for developing respiratory distress syndrome (RDS).
Search strategy: Searches were made of the Oxford Database of Perinatal Trials, Medline (MeSH terms: pulmonary surfactant; limits: age groups; newborn infants), previous reviews including cross references, abstracts, conference and symposia proceedings, expert informants and journal hand searching in the English language.
Selection criteria: Randomized controlled trials which compared the effect of prophylactic natural surfactant administration (surfactant obtained from human or bovine sources, either modified with additional phospholipids or not) administered to high risk preterm newborns at or shortly after birth in order to prevent respiratory distress syndrome, other complications of prematurity, and mortality.
Data collection and analysis: Data regarding clinical outcomes including 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 reviewer. Data analysis was done in accordance with the standards of the Cochrane Neonatal Review Group.
Main results: All of the included studies note an initial improvement in respiratory status and a decrease in the risk of respiratory distress syndrome in infants who receive prophylactic natural surfactant extract. The meta-analysis supports a decrease in the risk of pneumothorax (typical relative risk 0.35, 95% CI 0.26, 0.49; typical risk difference -0.15, 95% CI -0.20, -0.11), a decrease in the risk pulmonary interstitial emphysema (typical relative risk 0.46, 95% CI 0.35, 0.60; typical risk difference -0.19, 95% CI -0.25, -0.13), a decrease in the risk of neonatal mortality (typical relative risk 0. 60, 95% CI 0.44, 0.83; typical risk difference -0.07, 95% CI -0.12, -0.03), and a decrease in the risk of bronchopulmonary dysplasia or death (typical relative risk 0.84, 95% CI 0.75, 0.93; typical risk difference -0.10, 95% CI -0.16, -0.04. No differences are reported in the risk of intraventricular hemorrhage, patent ductus arteriosus, necrotizing enterocolitis or retinopathy of prematurity. Few data are available on long-term followup of treated infants.
Reviewer's conclusions: Prophylactic intratracheal administration of natural surfactant extract to infants judged to be at risk of developing respiratory distress syndrome (intubated infants <30 weeks gestation) has been demonstrated to improve clinical outcome. Infants who receive prophylactic natural surfactant extract have a decreased risk of pneumothorax, a decreased risk of pulmonary interstitial emphysema, a decreased risk of mortality, and a decreased risk of bronchopulmonary dysplasia or death.