Effects of inhalation of perfluorocarbon aerosol on oxygenation and pulmonary function compared to PGI2 inhalation in a sheep model of oleic acid-induced lung injury

Abstract

Objective: To evaluate the effects of PFC aerosol compared to PGI2 aerosol and NaCl aerosol on gas exchange and lung mechanics in oleic acid-induced acute lung injury. Design: A prospective, controlled, randomised, in vivo animal laboratory study. Setting: Research laboratory at an university hospital. Subjects: Twenty one (n = 21) adult sheep of either gender weighing 26.8 ± 6.4 kg. Interventions: The animals were randomised to three groups: PFC aerosol (perfluorooctane), PFC group; prostacyclin aerosol (Flolan), PGI2 group; and NaCl aerosol (0.9% sodium chloride solution), control group. After induction of anaesthesia and placement of vascular catheters, lung injury was induced with 0.12 ml·kg-1 oleic acid. Aerosols were continuously administered for 2 h using a jet nebuliser. Gas exchange, pulmonary mechanic, and haemodynamic parameters were obtained at regular intervals. Measurements and main results: PFC aerosol increased oxygenation (PaO2 15 min after the initiation of treatment up to 120 min (P < 0.05). Transpulmonary shunt improved in the PFC group (P < 0.05) while it did not change in the two other groups. PFC aerosol reduced maximum airway pressure (Pmax) (median) significantly from (median) 38 mbar to 32 mbar (P < 0.05). Static compliance improved significantly in the PFC group (P < 0.05). Conclusion: The inhalation of a PFC aerosol led to a significant improvement in pulmonary mechanics and gas exchange, which was not observed in the other two groups. These data suggest that a small dose of perfluorocarbon will have beneficial effects on gas exchange and respiratory mechanics. Therefore, the non-invasive aerosol application technique seems to be a reasonable alternative to administer perfluorocarbons in severe lung injury.