Effect of partial liquid ventilation on pulmonary vascular permeability and edema after experimental acute lung injury

We evaluated the effects of partial liquid ventilation (PLV) with two diffe rent dosages of the perfluorocarbon LiquiVent (perflubron) on pulmonary vas cular permeability and edema formation after oleic acid (OA)-induced acute lung injury in dogs. We used imaging with positron emission tomography to m easure fractional pulmonary blood flow, lung water concentration (LWC), and the pulmonary transcapillary escape rate (PTCER) of Ga-68-labeled transfer rin at 5 and 21 h after lung injury in five dogs undergoing conventional me chanical ventilation (CMV), five dogs undergoing low-dose PLV (perflubron a t 10 ml/kg), and four dogs undergoing high dose PLV (perflubron at 30 ml/kg ). A positive end-expiratory pressure of 7.5 cm H2O was used in all dogs. A fter OA (0.08 ml/kg)induced lung injury, there were no significant differen ces or trends for PTCER or LWC at any time when the PLV groups were compare d with the CMV group. However, lung tissue myeloperoxidase activity was sig nificantly lower in the combined PLV group than in the CMV group (p = 0.016 ). We conclude that after OA-induced lung injury, the addition of PLV to CM V does not directly attenuate pulmonary vascular leak or lung water accumul ation. Rather, the benefits of such treatment may be due to modifications o f the inflammatory response.