Combining partial liquid ventilation with nitric oxide to improve gas exchange in acute lung injury

Objective: To assess the effects of increasing concentrations of inhaled nitric oxide (NO) during incremental dosages of partial liquid ventilation (PLV) on gas exchange, hemodynamics, and oxygen transport in pigs with induced acute lung injury (ALI). Design: Prospective experimental study. Setting: Experimental intensive care unit of a university. Subjects: 6 pigs with induced ALI. Interventions: Animals were surfactant-depleted by lung lavage to a partial pressure of oxygen in arterial blood (PaO₂) < 100 mmHg. They then received four incremental doses of 5 ml/kg perflubron (LiquiVent). Between each dose the animals received 0, 10, 20, 30, 40, and 0 parts per million (ppm) NO. Measurements and main results: Blood gases, hemodynamic parameters, and oxygen delivery 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 maximum effect at 30 ± 10 ppm NO. The 5 ml/kg perflubron dose led to a significant decrease in mean pulmonary artery pressure, which decreased further 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 having any deleterious effect on measured systemic hemodynamic parameters. Received: 29 April 1996 Accepted: 24 October 1996