The effect of gastroschisis on experimental diaphragmatic hernia in fetal rabbits.

Purpose: In this study, the authors analyzed the effect of experimentally induced gastroschisis on pulmonary hypoplasia in fetal rabbits with congenital diaphragmatic hernia (CDH).

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

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

Conclusions: Pulmonary hypoplasia seen in newborn rabbits after experimentally induced diaphragmatic hernia is less severe in those rabbits with both gastroschisis and DH.