Abstract

It has been known for about 30 years that lack of surface tension reducing substances (‘surfactant’) in the lungs of premature infants is largely responsible for the development of hyaline membrane disease or respiratory distress syndrome (RDS). About 50% of premature babies develop RDS, characteristically showing tachypnoea, chest retractions and worsening cyanosis. Many babies die of it or suffer complications. Mechanical ventilation is the main treatment, supporting respiratory function until maturing alveolar lining cells synthesise adequate surfactant. Despite its inherent risks it has proved very successful, but drugs which can lower surface tension in the lungs may improve outcome further.