The effect analysis and comparison between gastroschisis and tracheal ligation on experimental diaphragmatic hernia in fetal rabbits.

Purpose: The authors analyzed and compared the effects of experimentally induced gastroschisis and tracheal ligation on pulmonary hypoplasia in fetal rabbits with congenital diaphragmatic hernia.

Methods: Twenty-three pregnant rabbits underwent fetal surgery on gestational day 24 through 27. Left diaphragmatic hernia was created in 1 fetus (DH group) from each rabbit, and a left diaphragmatic hernia with gastroschisis (GS group) or tracheal ligation (TL group) was created in another fetuses. The fetuses were delivered on gestational day 27 through 33. Histologic and morphometric examination of the lungs were performed in each group.

Results: In the DH group, the lungs were hypoplastic with a decrease in lung weight to body weight ratio and an increase in pulmonary arterial wall thickness. The alveolar septae were markedly thickened and diminished alveolar air spaces. In GS and TL groups, the alveolar septae were thickened but narrower than those of the DH group, air spaces were increased, and the pulmonary arterial wall was only slightly thickened.

Conclusions: Pulmonary hypoplasia seen in newborn rabbits after experimentally induced diaphragmatic hernia is less severe in those rabbits with concurrently made gastroschisis or tracheal ligation. From the histologic viewpoint, the effects of gastroschisis and tracheal ligation on pulmonary hypoplasia in diaphragmatic hernia have no differences.