Purpose  

The aim of this study was to analyze the effect of iatrogenic gastroschisis on pulmonary hypoplasia in fetal rabbits with congenital diaphragmatic hernia (CDH).

Materials and methods  

A total of 30 pregnant rabbits received fetal surgery on gestational day 23. A left diaphragmatic hernia was created in one end fetus (DH group) of each rabbit, and the other end fetus of the same rabbit received sham thoracotomy as control (CR group). Another 19 pregnant rabbits underwent partial resection of the diaphragm in both end fetuses on gestational day 23, and then artificial gastroschisis was performed on one end fetus (GS group) on gestational day 26, while the other end remained as control (CGS group). The fetuses were harvested on gestational day 30. The histological and morphometric evaluation of lungs and livers of the end fetuses in each group was conducted.

Results  

In the DH group, the lungs were hypoplastic with a decrease in the total lung weight to body weight ratio, and remarkable thickening in alveolar septa. The lung vessels showed significantly thicker arterial walls when compared with those from control fetuses. The pathological finding in the CGS group was similar to that of the DH group. The thickness of the alveolar septa and of the pulmonary arterial walls showed no significant difference among the GS group, DH group and the CGS group. The ratio of liver weight to body weight increased notably in the GS group, DH group and CGS group compared with that in the CR group.

Conclusions  

In the fetal rabbit models of CDH, pulmonary hypoplasia is the most significant pathological feature. Iatrogenic gastroschisis does not improve pulmonary maturation due to the active growth of the liver that herniates into the thoracic cavity.