Partial liquid ventilation with small volumes of FC 3280 increases survival time in experimental ARDS

The aim of this study was to determine the prolonged effects of sequential doses of a highly purified perfluorocarbon (FC 3280) on gas exchange and survival time in experimental acute respiratory distress syndrome (ARDS). The study was prospective, randomized and controlled. Twelve pigs (body weight 30 +/- 5 (mean +/- SD) kg) were surfactant-depleted by repetitive lung lavages, reducing arterial oxygen tension (Pa,O2) to 6.9 +/- 1.6 kPa (52 +/- 12 mmHg) (mean +/- SD) at an inspired oxygen fraction (Fi,O2) of 1.0. They were then randomized to receive partial liquid ventilation by sequential intratracheal application of 7.5 mL.kg-1 FC 3280 at 30 min intervals to a cumulative dose of 15 mL.kg-1 (treatment group), or to receive no further treatment (control group). Haemodynamics and gas exchange were assessed at 30 min intervals after instillation, and hourly afterwards in both groups until death. In the treatment group, Pa,O2 was 8.9 +/- 4.4 kPa (67 +/- 33 mmHg) after 7.5 mL.kg-1 FC 3280 and 14.1 +/- 9.9 kPa (106 +/- 74 mmHg) after 15 mL.kg-1 FC 3280 (NS). In the control group, gas exchange remained unchanged. Haemodynamics were stable in the treatment group and deteriorated in the control group. Peak airway pressures and dynamic compliance were not significantly affected in the treatment group. Mean survival time was 8.2 +/- 4.5 h in the treatment group and 1.8 +/- 1.4 h in the control group (p < 0.05). Upon histological examination, both study groups were not significantly different in total lung injury scores. We conclude that partial liquid ventilation with small volumes of FC 3280 provides improvement in gas exchange and increases survival time in experimental acute respiratory distress syndrome.