Experimental study in partial liquid ventilation for acute respiratory failure after ischemia reperfusion pulmonary injury in a rabbit model

Abstract

Partial liquid ventilation (PLV) using perfluorooctylbromide (PFOB) was studied for use in treating experimental animal models in which acute respiratory failure was caused by hypoxia, oleic acid lung injury, or saline lung lavage. Clinical trials are currently being conducted in the United States. We studied the effectiveness of PLV with PFOB in treating acute respiratory failure after ischemia reperfusion pulmonary injury in a rabbit model; left lung ischemia was induced with a hilar clamp. Ninety minute later, the clamp was removed for reperfusion. Fifteen Japanese white rabbits weighing from 2.5 to 3.2 kg were divided into three groups-conventional mechanical ventilation (CMV) after reperfusion, PLV after reperfusion and controls (conventional mechanical ventilation without ischemia reperfusion injury). In the PLV group, a dose of 7 ml/kg PFOB was administered through an endotracheal tube. In the CMV group, PaO2 value decreased to 79 +/- 13 mmHg 120 min after reperfusion, significantly lower than in the PLV group 404 +/- 70- or controls -494 +/- 61-. PaCO2 was significantly higher in the CMV group-61.9 +/- 14.4 mmHg- than in the PLV group-45.7 +/- 6.1- or controls-32.1 +/- 2.2. Peak airway pressure was slightly higher in the CMV group-19.0 +/- 4.9-than in the PLV group-18.2 +/- 5.4- or controls-16.2 +/- 1.8. mPAP/mSAP did not differ significantly among groups. The heart rate decreased in the CMV and PLV groups, but was unchanged in controls. Microscopic studies revealed markedly reduced alveolar hemorrhage, lung fluid accumulation, and inflammatory infiltration in the PLV group, compared to the CMV group. PLV thus is effective in improving gas exchange and preventing pulmonary injury in acute respiratory failure after ischemia reperfusion injury in a rabbit model.