Animal models and clinical pilot studies of surfactant replacement in adult respiratory distress syndrome.

This brief review describes the pathogenesis of the adult respiratory distress syndrome (ARDS) and the rationale for surfactant replacement therapy. In four animal models in which respiratory failure was induced by: 1) lung lavage leading to surfactant depletion; 2) free oxygen radicals; 3) anti-lung serum; or 4) influenza virus, surfactant instillation consistently led to an improvement in gas exchange and lung mechanics. Data from a first clinical trial show that surfactant instillation also improved lung function in a 4 year old patient with severe respiratory failure. It is speculated that surfactant replacement therapy may soon become accepted as a therapeutic measure in ARDS.