Effects of Ventilation Style on Surfactant Treatment Response in Premature Lambs. † 910

Abstract

Effects of ventilation style on long term responses to surfactant have not been studied in the surfactant treated preterm. Preterm lambs were delivered at 130±1 d gestation (term 150 d) and treated with 100 mg/kg lipid extracted sheep surfactant. Three styles of ventilation that are at the extremes of clinical practice were used: (L) low rate of 15 breath/min, tidal volume 13 ml/kg; (H) high rate of 50 breath/min, tidal volume 8 ml/kg; (HFV) Sensomedics 3100 high frequency ventilation. Normal blood gas values(PCO2 45-50 mmHg) were achieved for all animals. Groups of 4 to 6 lambs(total N=60) were killed at 2, 5, 10 and 24h to recover alveolar wash (AW) and lung tissue for biochemical analysis. Mean airway pressure (MAP, cmH2O), dynamic compliance (Comp. ml/cmH2O·kg), functional residual capacity (FRC, ml/kg), lung volume at 40 cmH2O(V40, ml/kg),% functional large aggregate surfactant (%L) in AW, total protein in AW (protein, mg/kg) at 24h of age are in the table.