COMBINING PARTIAL LIQUID VENTILATION WITH NITRIC-OXIDE TO IMPROVE GAS-EXCHANGE IN ACUTE LUNG INJURY

Objective: To assess the effects of increasing concentrations of inhal ed nitric oxide (NO) during incremental dosages of partial liquid vent ilation (PLV) on gas exchange, hemodynamics, and oxygen transport in p igs with induced acute lung injury (ALI). Design: Prospective experime ntal study. Setting: Experimental intensive care unit of a university. Subjects: 6 pigs with induced ALI. Interventions: Animals were surfac tant-depleted by lung lavage to a partial pressure of oxygen in arteri al blood (PaO2) < 100 mmHg. They then received four incremental doses of 5 ml/kg perflubron (LiquiVent). Between each dose the animals recei ved 0, 10, 20, 30, 40, and 0 parts per million (ppm) NO. Measurements and main results: Blood gases, hemodynamic parameters, and oxygen deli very were measured after each dose of perflubron as well as after each NO concentration. Perflubron resulted in a dose-dependent increase in PaO2. At each perflubron dose, additional NO inhalation resulted in a further significant (ANOVA, p < 0.05) increase in PaO2, with a maximu m effect at 30 +/- 10 ppm NO. The 5 ml/kg perflubron dose led to a sig nificant decrease in mean pulmonary artery pressure, which decreased f urther with higher NO concentrations. Conclusions: PLV can be combined with NO administration and results in a cumulative effect on arterial oxygenation and to a decrease in pulmonary artery pressure, without h aving any deleterious effect on measured systemic hemodynamic paramete rs.