Comparison of rejection rate and functional outcome of small bowel transplantation alone or in conjunction with the ileocecal valve versus combined small and large bowel transplantation

Abstract

Preservation of the ileocecal valve improves absorptive function and decreases the amount of small bowel needed for survival in patients with short gut syndrome. We compared the results of small and large bowel transplant (SLBTx), small bowel transplant only (SBTx), and SBTx with the ileocecal valve (ICVTx) in a porcine model. Total enterectomy was performed on 18 Yorkshire-Landrace pigs followed by orthotopic SBLTx (n = 6), SBTx (n = 6), and ICVTx (n = 6). A jejunostomy and an ileostomy were constructed for biopsies. Overall mean survival was 17 d with no statistically significant difference between groups. Rejection was seen in 6/6 SLBTx, 4/6 SBTx, and 4/6 ICVTx recipients. Acute rejection was seen in 84.3% of SLBTx, 52.3% of SBTx, and 42.5% of the ICVTx mucosal biopsy samples. Two cases of intra-abdominal infection were in the ICVTx group only. Weight loss was 147 g/d in the SLBTx group, 643 g/d in the SBTx group, and 393 g/d in the ICVTx group. While the functional outcome after SLBTx and ICVTx was noticeably better than the SBTx group, the increased rejection and intra-abdominal infection rates make transplanting the large bowel or the ileocecal valve a less attractive clinical option.

Review of Various Techniques of Small Bowel Transplantation in Pigs

“…Less frequently, SBTx additionally included parts of the duodenum. Several teams transplanted the small bowel with parts of the large bowel, in some cases up to the sigmoid colon [8][9][10]. In other procedures, shorter parts of the small bowel were used as grafts [11].…”

“…Jejuno-jejunostomies are carried out mainly end-to-end [4, 15-17, 25, 26]; however side-to-side [8] and end-to-side anastomosis [12] have been also described. Duodeno-jejunal anastomosis has been performed using side-to-side [10,26] and endto-end [9,13]. Less frequent is duodenal-doudenal anastomosis, which is carried out side-to-side or endto-end [28,31].…”

“…There exist a few models in which the portal vein of the donor and recipient was anastomosed. If the dSMV is used, it is usually anastomosed to the superior mesenteric vein (rSMV), the inferior vena cava or the iliac vein of the recipient [5,10,13,17,24,35]. The dSMV-rSMV anastomosis is performed end-to-end either with continuous 6-0 Prolene [4,28], 5/6-0 monofilament [21,35], or 7-0 PDS [14] sutures or interrupted 8-0 Prolene sutures [15].…”

“…Isolation of the vascular pedicles was mostly perfomed in situ after flushing the bowel [3-5, 13-16, 21, 22, 24, 26, 27]. Back-table preparation was conducted only in very few cases [10,25].…”

“…The venous anastomosis to the iliac vein is conducted end-to-end using a continuous 5/6-0 monofilament suture [21]. The portal vein of the donor (dPV) is usually anastomosed to the PV of the recipient (rPV) [10,18,23,28], using the ''piggyback'' technique, in which the dPV is sutured end-toside to the rPV using 6/0 Prolene continuous sutures [7,32]. Alternatively, the dPV is anastomosed to the inferior vena cava of the recipient through an end-to-side anastomosis with continuous 5-0 Prolene sutures [12] (Fig.…”