Search

Extrinsic denervation and lymphatic disruption impair nutrient absorption after small bowel transplantation. The present study was undertaken to determine whether adding the ileocecal valve with or without the ascending colon would improve the function of a segmental intestinal graft. Five groups of Lewis rats (n = 10/group) were studied. Group I had a sham laparotomy. Groups II, III, IV, and V had the native jejunum, ileum, and cecum replaced with a graft. Inbred Lewis rats were used as isogeneic donors for the transplants to avoid the confounding effect of graft rejection. Group II had the entire jejunum and ileum transplanted. Group III had 20 cm of terminal ileum transplanted. Group IV had 20 cm of the terminal ileum including the ileocecal valve transplanted. Group V had 20 cm of the terminal ileum, the ileocecal valve, and the ascending colon transplanted. The terminal ileum-transplanted and terminal ileum/ileocecal valve-transplanted groups lost more than 25% of their preoperative weight by the end of the second postoperative week; most of these animals were killed because of inanition. In contrast, the sham laparotomy, jejunum/ileum-transplanted, and ascending colon-transplanted groups remained healthy until completion of the study on the 28th postoperative day. The ascending colon-transplanted group had slower intestinal transit and less bacterial contamination of the terminal ileum compared with the terminal ileum-transplanted and terminal ileum/ileocecal valve-transplanted groups (P < 0.05). Transplantation of the ascending colon and the ileocecal valve significantly improves the function of segmental small bowel isografts in rats. These data suggest that adding a colonic segment may be a simple method to improve the function of short-segment cadaveric and living-related intestinal grafts in humans.

Acute massive intestinal ischemia is an abdominal catastrophe. Prompt diagnosis and restoration of blood flow is essential; otherwise, massive intestinal resection occurs, leading to death or, in the survivors, intestinal cripples. In this study, the time of warm reversible ischemia in the canine intestine was explored. After this time was established, fluids and antibiotics were administered to note change in survival times. Massive intestinal ischemia (superior mesenteric artery was clamped) was tolerated without death for five hours (20 dogs in each group). With six hours of ischemia, a 10 per cent mortality rate occurred; with seven hours of ischemia, a 90 per cent mortality rate occurred. These dogs had a maintenance of 75 milliliters of fluid administered per hour. Using this group of dogs as the control (that is, the group with seven hour clamping time of the superior mesenteric artery with maintenance intravenously administered replacement), fluids were given to dogs in the experimental group to keep the pulmonary artery wedge pressure at a normal value (average of 300 milliliters per hour). This group of dogs had an increased survival rate of 40 per cent (ten dogs). Antibiotics were given to the dogs in the experimental group both before and after clamping, increasing the over-all survival rate to more than 80 per cent (46 dogs). Aggressive fluid replacement and antibiotic coverage may lengthen the so-called golden period in which intestinal ischemia may be reversed by revascularization.

Graft-versus-host disease was studied on the 10th and 14th postoperative days in Lewis x Brown Norway F1 rats (LBN-F1) receiving Lewis accessory heterotopic intestinal allografts. LBN-F1 isograft recipients and LBN-F1 rats were used as controls. The rats were injected with sheep erythrocytes five days before sacrifice. Rats with graft-versus-host disease had progressive loss of the normal architecture of the lymphoid organs. Skin, liver, colon, and salivary glands were infiltrated with immunoblasts and had patchy areas of necrosis. Concurrent with these changes, there were significant, progressive reductions in hemolytic titers, splenocyte plaque-forming counts, viable splenocytes, and the in-vitro splenocyte response to stimulation with concanavalin A. Graft-versus-host disease following intestinal allotransplantation damages the host's lymphoid tissues, producing profound immunosuppression. This finding has implications for clinical intestinal transplantation.