Surfactant therapy for acute lung injury/acute respiratory distress syndrome.

Currently, three phase III surfactant replacement trials for acute lung injury (ALI)/acute respiratory distress syndromes (ARDS) patients are underway. Although the efficacy of surfactant replacement therapy will first have to be proved in these phase III trials, recent reports indicate some enticing possibilities for the future of surfactant therapy.Patients requiring mechanical ventilation show alterations in their endogenous surfactant composition. Depending on the type of lung injury or the elapsed time, modifications to surfactant preparations could enhance the efficacy of these preparations. Surfactants that closely resemble natural surfactant, especially those containing surfactant proteins (SP-B/C) and nonphospholipids (cholesterol), are able to restore normal surfactant physiology. Furthermore, lipids that are able to withstand degradation by lipases could further enhance surfactant therapy.If surfactant therapy fulfills the promises expected from the ongoing phase III trials, future surfactant preparations may even enhance therapy efficacy and restore the altered endogenous surfactant pool as soon as possible.