Long-term tidal liquid ventilation in premature lambs: physiologic, biochemical and histological correlates.

Chronic lung disease in infants continues to be problematic. Tidal liquid ventilation (TLV) improves lung mechanics and provides effective gas exchange. We hypothesized that premature lambs could be supported safely with TLV and evaluated 9 preterm lambs (132 days gestation) on TLV up to 72 h. Results (mean +/- SEM): pH 7.36 +/- 0.003, PaCO2 44 +/- 0.34 mm Hg, PaO2 170 +/- 4.8 mm Hg, compliance=1.65 +/- 0.24 ml/cm H2O/kg, mean arterial blood pressure=53 +/- 0.08 mm Hg, heart rate=189 +/- 1.5 bpm. Blood perflubron levels were 6.0 +/- 0.24 microg/ml over 24 h. Tissue perflubron levels increased from 81 +/- 7.0 microg/g at 24 h to 108 +/- 15 microg/g at 72 h (p<0.05). There was a difference in perflubron concentrations as a function of tissue (p<0.001) that correlated to lipid levels (r2=0.93, p<0.01). These data demonstrate that TLV is both safe and effective up to 72 h in premature lambs.