Experimental model of living donor small intestinal transplantation: surgical technique description and comparison of functional, metabolic and histological results between mesenteric-cava and mesenteric-portal anastomosis

Abstract

Intestinal failure (FI), new term for short bowel syndrome, is defined as intestinal incapacity in maintaining nutrition, hydroelectrolytic control and, in children, growth development. Thus, the patient becomes dependent on total parenteral nutrition (NPT) for their survival. The main causes of intestinal failure in children are congenital or acquired defects that can motivate large intestinal resections, with emphasis on gastroschisis, necrotizing enterocolitis, Atresias and Volvos of large portions of the intestine. However, IF may not be related to loss of large intestinal mass, but rather to motility or absorbable disturbances of the gastrointestinal tract (Intestinal pseudo-occlusion syndrome). The essential therapy for these cases is intestinal rehabilitation, based on a long-term parenteral nutrition program, until the growth and functional recovery of the intestine occurs. However, there are ineffective situations, such as in cases of total resection of the small intestine. For these cases, the definitive option would be small bowel transplantation. We know that in our country there is a shortage of cadaver donors in ideal conditions for capturing the small intestine and, therefore, the living donor transplantation would be consolidated as a feasible and safe option, as well as already consecrated for liver kidney. OBJECTIVE: The present experimental study, with young and adult pigs, aims to standardize the surgical technique of living donor small bowel transplantation, with metabolic, histological and molecular studies. In addition, two types of venous anastomosis of the graft will be compared in the receiving animal: Portal territory and inferior vena cava. METHODS: 14 living donor small bowel transplantation will be performed. In seven receptors the venous anastomosis will be performed with the inferior vena cava, in the other seven the vein will be anastomosed in vessels of the portal territory (port vein or superior mesenteric vein). The animals will be kept alive for 07 days and the metabolic and hemodynamic analyses were measured on days 0, 2, 4 and 7. Liver and intestine biopsies will be performed intraoperatively and on day 7 for histological and molecular studies. The data will be compared in order to define which technique is more beneficial. (AU)