High frequency oscillatory ventilation (HFOV) of the perfluorocarbon-filled(PFC) lung offers the potential to improve mechanics and enhance lung protection during support of the acutely injured lung. In the present study, we compared histologic measures of injury following high frequency oscillation of the gas and PFC-filled lung (HFO-PLV) in an animal model of acute lung injury. METHODS: Nine healthy pigs (mean weight 26 kg) were anesthetized, instrumented, and underwent repetitive saline lavage until PaO2 was consistently ≤ 90 torr (FiO2 1.0) for one hour. Pigs were then converted to gas HFOV (f 7 Hz, MAP 12 cm H2O over MAP on CMV,ΔP titrated to PaCO2 45-55 torr). Six animals received 30 ml/kg of PFC over one hour (Liquivent®, perflubron, Alliance Pharmaceutical Corp.). HFO was continued at f 4 Hz for two hours. HFOV controls underwent sham dosing and analysis at similar intervals. Histologic evidence of lung injury·was quantitated using a five point scoring system by a blinded pathologist. HFO-PLV animals and HFOV controls were compared using an unpaired, two-tailed Mann-Whitney U test. RESULTS: see table below. Data are presented as mean score (standard deviation), * p = 0.024. CONCLUSIONS: We demonstrated a significant difference in histologic signs of lung injury after two hours of ventilation using HFO-PLV. HFO-PLV may offer enhanced lung protection while supporting gas exchange in the acutely injured lung. This work was supported in part by Hoechst-Marion Roussel (Frankfurt, Germany).

Table 1
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