ObjectiveTo demonstrate the efficacy of partial perfluorocarbon liquid ventilation in a large animal model of acute respiratory failure.DesignProspective, randomized, controlled trial.SettingAnimal laboratory at a university medical center.SubjectsTen adult sheep, weighing 53.0 plus minus 2.8 kg.InterventionsAfter assessment of baseline physiologic data, acute respiratory failure was induced by right atrial injection of oleic acid (0.2 mL/kg). Five animals (partial liquid ventilation group) underwent sequential intratracheal dosing of 10 mL/kg of perflubron at 30-min intervals to the following cumulative doses: 10, 20, 30, 40, and 50 mL/kg. The remaining five animals were gas ventilated (control group). Physiologic data were assessed at 30-min intervals in both groups for the 2.5-hr experimental period or until death.Measurements and Main ResultsWhen compared with control animals, intratracheal perfluorocarbon instillation resulted in significant improvements in arterial oxygen saturation (arterial oxygen saturation after 50 mL/kg: partial liquid ventilation, 96 plus minus 3%; control, 55 plus minus 8%; p equals .001) and physiologic shunt (physiologic shunt after 50 mL/kg dose: partial liquid ventilation, 22 plus minus 8%; control, 64 plus minus 5%; p equals .004). Oxygen delivery improved with perfluorocarbon instillation, but this improvement was not significant. No significant difference in pulmonary compliance was observed during partial liquid ventilation when compared with controls (pulmonary compliance: partial liquid ventilation, 0.43 plus minus 0.04 mL/cm H2O/kg; control, 0.53 plus minus 0.03 mL/cm H2O/kg; p equals .102).ConclusionsPartial liquid ventilation with perflubron provides effective improvement in gas exchange in an adult animal model of respiratory failure.(Crit Care Med 1996; 24:1208-1214)