Effects of partial liquid ventilation on unilateral lung injury in dogs

Study objective: The overall physiologic effect of partial liquid ventilation (PLV) in the setting of unilateral lung injury, remains unclear. Therefore, we evaluated the effect of PLV on gas exchange in unilateral lung injury. Design and methods: Left unilateral lung injury, was induced in 14 adult dogs by oleic acid instillation into a left pulmonary artery. The animals were divided into two groups: gas ventilation (GV) and PLV. During both GV an PLV, systemic blood gas levels were analyzed. Oxygen consumption (V-O2), carbon dioxide production (V-CO2) and pulmonary Wood flow (Q) of both the right lung (uninjured lung) and left lung (injured lung) were measured. Results: During PLV, V-O2 of the injured left lung (V-O2-injurcd), V-CO2, of the injured left lung (V(CO)2-injured), and Q of the injured left lung (Q-injured) were greater than those in GV (V-O2-injured, 41.6 mL/min vs 23.4 mL/min, p = 0.006; V-CO2-injured, 34.4 mL/min vs 25.5 mL/min, p = 0.026; and Q-injured, 0.47 L/min vs 0.22 L/min, p = 0.002, respectively). However, overall Pa-O2 during PLV was less than that during GV, likely due to either a redistribution of Q toward the injured lung (PLV Q-injured, 0.47 L/min vs GV Q-injured, 0.22 L/min, p = 0.002) or reduced gas exchange efficiency in the healthy lung. Conclusions: We conclude that in our model, PLV increases V-O2 and V-CO2 in the injured lung. However, over all gas exchange efficiency is reduced.