The goal of this study was to compare the effectiveness of the exogenous surfactants Infasurf and Exosurf in reestablishing surfactant function inhibited by severe smoke inhalation. Mongrel dogs (n = 17) were anesthetized, placed on a ventilator (40% O2), and surgically prepared for hemodynamic and blood gas measurements; venous admixture (QVA/QT) and static lung compliance (Cstat) were calculated. At the conclusion of the experiment, lung samples were taken for lung water and dynamic surface tension (DST, Wilhelmy balance) measurements. Following baseline measurements, dogs were randomly separated into four groups: Group I, smoke+sham instillation; Group II, smoke+saline instillation: Group III, smoke+Exosurf instillation; and Group IV, smoke+Infasurf instillation. The surfactants (Infasurf and Exosurf, 100 mg/kg) or saline (same volume as surfactants) were instilled into the lungs via suction catheter immediately following smoke exposure. Smoke inhalation caused a similar increase in QVA/QT and fall in PaO2 and Cstat in all groups that improved only with Infasurf instillation (Group IV). DST was significantly improved by Infasurf compared with all other groups. We conclude that Infasurf restores normal DST, inhibited by wood smoke, improving lung function. Exosurf was ineffective in the treatment of wood smoke inhalation.