Technical aspects of pig model in living-related small intestinal transplantation

We established a living-related small intestinal transplantation model of the pig. Donor operation: A 3 m of ileal segment from 10 cm proximal to the ileocecal valve was harvested with vascular pedicles. Superior mesenteric artery and vein (SMA, SMV) were dissected and divided just distal to the colonic branches. Recipient operation: The infrarenal aorta and inferior vena cava (IVC) were exposed, and end-to-side anastomoses were performed between SMA and aorta, and SMV and IVC with 7-0 prolene interrupted sutures. After establishment of this technique, 20 pigs were operated: 9 cases were autotransplantation and 11 cases were allotransplantation. The U-shaped fixation of mesentery to the retroperitoneum was performed in the latter 18 pigs. Using this technique, the entire length of the jejunum, proximal ileum and 10 cm of terminal ileum of the donor could be preserved. Six autotransplanted (66.7%) and 11 allotransplanted pigs (72.7%) survived more than 1 week, respectively. Two pigs from the former group developed intestinal perforation due to strangulation. In donor operation, the preservation of the most distal colonic branches of SMA and SMV could maintain adequate blood supply of the terminal ileum and colon of the donor. Fixation of graft mesentery to the retroperitoneum in a U-shaped fashion was also effective in avoiding intestinal strangulation.