Establishment of respiratory distress syndrome in premature piglets treated with mechanical ventilation and porcine surfactant / 中华围产医学杂志

ABSTRACT

Objective To establish a respiratory distress syndrome (RDS) model of piglets and assess the therapeutic effect of pulmonary surfactant (PS) on gas exchange, lung mechanics and morphology. Methods Preterm newborn piglets were delivered by cesarean section at 94~97 days of gestation for determination of lung immaturity. Littermates were randomly divided into 4 groups Group C50 were treated with 50 mg/kg for 6 h and group C100 with 100 mg/kg Curosurf; group C was the control group and group N received no ventilation. Blood-gas analyses and lung mechanic measurement were performed per hour. At the end of the experiment, the lungs were processed for biochemical, biophysical and histopathological analyses. Results Surfactant deficiency in RDS was shown with the low total phospholipids (TPL) level in bronchoalveolar lavage (BALF) in premature piglets at 94~97 days of gestation with marked difficulty in spontaneous respiration and morphological evidence of poor alveolar aeration and paucity of lamellar bodies in type Ⅱ alveolar epithelial cells. The group C had typical lung injury of RDS, the C100 and C50 group had variable but significantly improved alveolar phospholipid, alveolar aeration and wet-to-dry lung weight ratio. PaO_2/FiO_2 was improved from (92?37) mm Hg to (235?137) mm Hg, and the dynamic compliance (Cdyn) from (0.48?0.08) to (0.76?0.29) ml/(cm H_2O?kg) in group C100. But mild effects was shown in group C50. Conclusion A premature piglet RDS model is established and valuable for investigation of mechanism of lung injury in early life after born.