Surfactant

Surfactant is a mixture of phopholipids and proteins which is produced by type II pneumocytes from 24 weeks of gestation onwards. Surfactant has the following functions:

• reduction of surface tension, preventing collapse of alveoli
• facilitation of gas transport between air and fluid phases

Neonatal respiratory distress syndrome (RDS) is a disease of premature babies which results primarily from a deficiency of surfactant.

Surfactant used in treating neonatal RDS may be:

• synthetic:
  • contains phospholipid but no surfactant proteins
• animal-derived:
  • contains phospholipid and surfactant proteins

Recent evidence suggests that the animal-derived surfactant is more effective but there is some concern about the possibility of disease transmission.

There is currently research into the use of surfactant in adult respiratory distress syndrome, but this is presently no further than the animal model and case report stage.