Respiratory distress syndrome (RDS) is a significant cause of illness in preterm infants. Respiratory distress syndrome is caused by a deficiency or a dysfunction of the chemicals that line the lung, called pulmonary surfactant. Numerous preparations that contain surfactants of either animal origin or synthetic design have been developed and tested to treat or prevent respiratory distress syndrome. In general, these surfactant preparations have decreased lung rupture (pneumothorax), decreased the risk of dying, and increased the number of survivors without lung damage. From previous research, the surfactants that are obtained from animals seem to have a better effect than the synthetic surfactants. This might be due to the surfactant proteins contained in animal surfactant that are absent in the previously available synthetic surfactants.
Recently developed synthetic surfactant preparations include whole surfactant proteins or parts of the proteins (called peptides) that act like surfactant protein. These preparations have been recently tested in comparison to the animal derived surfactant preparations.
Two recent trials of protein containing synthetic surfactant compared to animal derived surfactant preparations have demonstrated a trend towards decreasing death and decreasing rates of bowel disease (necrotizing enterocolitis), while other clinical outcomes were similar. Further studies will help refine recommendations concerning use of protein containing synthetic surfactants.