Evaluation of exogenous surfactant treatment strategies in an adult model of acute lung injury

of exogenous surfactant treatment strategies in an adult model of acute lung injury. J. AppZ. PhysioZ. 80(4): 1156-1164, 1996.~Two exogenous surfactant preparations [Survanta and bovine lipid extract surfactant (BLES)] were evaluated in saline lavage-injured adult sheep with two different delivery methods (instillation vs. aerosolization). Instilled BLES re-sulted in the greatest improvement in lung function, followed by aerosolized Survanta and then instilled Survanta. Aerosol-ized BLES was ineffective. Total surfactant recovery and distribution patterns were similar for Survanta and BLES for each delivery method tested. There were significant differ-ences, however, in the proportion of surfactant recovered in the alveolar wash relative to the lung tissue between the groups at killing. Moreover, the ratio of poorly functioning small surfactant aggregates to superior functioning large aggregates isolated from alveolar wash samples correlated with the physiological responses. The calculated contribution of secreted endogenous surfactant to the total alveolar phos-pholipid pool at killing was significantly greater for the aerosolized Survanta group compared with the aerosolized BLES group. This finding suggested that there were differ-ences in the interaction of the exogenous surfactants and their alveolar environments. We conclude that the response to exogenous surfactant in acute lung injury depends not only on the preparation used but also on how the surfactants are delivered to the injured lung. exogenous surfactant therapy; acute respiratory distress syndrome; pulmonary surfactant distribution; Survanta; bo-vine lipid extract surfactant ALTERATIONS of the endogenous surfactant system have been observed in patients with acute respiratory dis-tress syndrome (ARDS) and have been shown to contrib-ute to lung dysfunction in several animal models o