Influence of dexamethasone and surfactant in the vitality and lung function of preterm lambs born by cesarean section

The aim of this study was to assess the vitality and lung function of preterm lambs. Twenty seven preterm lambs were divided in four groups. Group I (n=6) preterm lambs/ control; group II (n=9) lambs born to mothers that were treated with dexamethasone antepartum; group III (n=6) lambs treated with surfactant; and group IV (n=6) lambs treated with surfactant and born to mothers that were treated with dexamethasone antepartum. The APGAR score was performed after birth (T ₀ ) and 15 minutes later (T _1/4 ) to assess vitality. The vital signs, blood gas analysis, spirometry and capnometry were assessed immediately after birth and continued until 48 hours. Chest radiographs were performed at T ₀ , T ₂₄ and T ₄₈ . Significant rectal temperature interactions occurred at T ₁ and T ₆ depending on the type of treatment used. All animals showed low pH values, which were associated with high pCO ₂ values and HCO ₃ -values that increased over time from immediately after birth to two days of age. Higher tidal volume values were observed at T _1/4 , T ₁ and T ₂₄ when the animals were not treated with surfactant. Capnometry showed significant interactions between treatments at T ₀ . Premature animals showed low vitality and impaired pulmonary function.