Intestinal damage in gastroschisis is independent of the size of the abdominal defect.

The intestinal damage in gastroschisis (GS) has been attributed to a narrow abdominal wall defect (AWD), among other causes, but this causal effect is difficult to prove in humans. The present experimental study was done to ascertain the damaging effect of clinically extrapolable mild and moderate constriction at the AWD on the intestine of fetuses with GS. AWDs of two different sizes were carried out in the fetal rabbit model: small-ring GS (1.5x bowel diameter, SRG) and large-ring GS (3x bowel diameter, LRG); a group of unoperated littermates served as controls. Fetal body weight, intestinal length and weight, bowel diameter and wall thickness, and histology were checked 7 days later. No statistical difference was found in body weight and bowel diameter among the groups. Intestinal length, weight, and wall thickness were significantly different in the GS groups compared to the controls, but no difference was found between the GS groups. Histology did not show venous stasis, ischemic lesions, or differences in the degree of edema between groups SRG and LRG. Mesothelial hyperplasia was seen in both GS groups. The intestinal changes in length, weight, diameter, wall thickness, and histology in GS should thus not be attributed to the diameter of the AWD.