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Objective: To evaluate the effect of low-bias flow oscillation (LBFO) with partial liquid ventilation (PLV) on perfluorochemical evaporation, histopathology, and oxidative tissue damage in an animal model of acute lung injury., Design: Prospective, randomized animal study., Setting: Research laboratory of a health sciences university., Subjects: Twelve New Zealand White rabbits., Interventions: Juvenile rabbits were anesthetized, paralyzed, and ventilated through a tracheostomy with either high-frequency oscillatory ventilation or LBFO. Lung injury was induced by repeated saline lavage, after which perflubron was instilled through a side port of the endotracheal tube. Lateral fluoroscopic images were performed at baseline and at various postfill intervals of animals in the high-frequency oscillatory ventilation-PLV and LBFO-PLV groups. The images were digitalized for computer analysis of the Lung Lucency Index, a surrogate marker of perflubron evaporation. Histopathologic evaluation was performed using a lung-injury scoring system. Malondialdehyde was measured in lung homogenates to assess oxidative damage., Measurements and Main Results: There were no significant differences in gas exchange and ventilator settings between groups throughout the experiment. At 300 mins, the high-frequency oscillatory ventilation-PLV group had a significantly higher Lung Lucency Index compared with the LBFO-PLV group in both dependent and nondependent lung regions (a high Lung Lucency Index correlates with increased perflubron loss). Malondialdehyde measurements were not different between groups. Animals treated with LBFO-PLV had a lower histopathologic lung-injury score compared with high-frequency oscillatory ventilation-PLV., Conclusion: LBFO-PLV is a viable mode of ventilation in a model of acute lung injury and is associated with significant preservation of perflubron in comparison with high-frequency oscillatory ventilation-PLV. The lower evaporative losses during LBFO-PLV were associated with improved histology scores.

Objective: To examine whether perfluorooctyl bromide (perflubron) is capable of protecting biological and nonbiological systems against oxidative damage through a mechanism independent of its known anti-inflammatory property., Design: A controlled, in vitro laboratory study., Setting: Research laboratory of a health sciences university., Subjects: Rat pulmonary artery endothelial cell cultures (biological system) and linoleic acid in sodium dodecyl sulfate micelles (nonbiological system)., Interventions: Rat pulmonary artery endothelial cells labeled with dichlorofluorescein diacetate and incubated with perflubron or culture media (control) were exposed to H2O2. H2O2-induced fluorescence of dichlorofluorescein diacetate was measured as an index of intracellular oxidative stress. In another experiment, linoleic acid in sodium dodecyl sulfate micelles was exposed to various concentrations of the azo initiator 2,2'-diazo-bis-(2-amidinopropane) dihydrochloride (2, 4, 20, and 50 mM) in the presence or absence of perflubron. Malondialdehyde measurements were obtained as a marker of oxidative damage to linoleic acid., Measurements and Main Results: Cell monolayers incubated with perflubron exhibited 66.6% attenuation in intracellular fluorescence compared with controls (p < .05). Linoleic acid in sodium dodecyl sulfate micelles incubated with perflubron and exposed to 2, 4, 20, or 50 mM of 2,2'-diazo-bis-(2-amidinopropane) dihydrochloride showed less evidence of lipid peroxidation as indicated by lower malondialdehyde measurements at 240 mins (10.6%, 16%, 41%, and 14.2%, respectively) compared with controls., Conclusions: Perflubron attenuates oxidative damage to both biological and nonbiological systems. This newly recognized property of perflubron is independent of its anti-inflammatory properties.