Evaluation of diluted amniotic fluid effects on histological changes of intestine of rabbit fetus with gastroschisis.

Amniotic fluid exchange is a method for prevention of intestinal damage in gastroschisis, but its techniques are different in studies. We investigated the effects of amnioinfusion exchange on histological changes of intestine and feasibility and safety of amniotic fluid exchange through central vein catheter (CVC) placed in pregnant rabbit uterus. A total of 15 pregnant New Zealand white rabbits were selected. Fetuses were randomly divided into three groups (case, control, sham). On gestational day 25, under general anesthesia with midline laparotomy, the graved bicornuate uterus was exposed. In controls, fetus abdomen was opened by a transverse incision in right lower quadrant region and intestines were eviscerated. In cases, after intestine evisceration, a central venous catheter was passed from mother skin and uterus and fixed to uterus wall. In shams, fetus was delivered on gestational day 32 and its abdomen was opened. In case group, after operation, 1-2 cc of warm saline solution was replaced through catheter every 6 h. On gestational day 32, fetuses of case and control groups were delivered. Mucosal and serosal thickness, muscle thickness, fibrin deposition, serosal collagen and ganglia were compared. Ten fetuses as shams, 7 fetuses as controls and 7 fetuses as case group were studied. Serosal thickness was 4.5 +/- 3.6 microm in shams, 64.2 +/- 28.7 microm in controls and 6 +/- 4.1 microm in cases. Serosal thickness in control group was higher than sham (P < 0.001) and case (P < 0.002) groups. In case group, infiltration of inflammatory cells with mild edema without fibroblast infiltration was seen. Application of the CVC technique was found to be a simple procedure that effectively decreased serosal inflammatory response of intestine in gastroschisis.