Portal Vein Anastomosis with using Growth Factor for Preventing Stricture and Thrombosis following Auxiliary Partial Liver Transplantation in Rat

ABSTRACT

PURPOSE: To overcome donor shortage, reduced-size liver transplantation, split-liver transplantation and partial liver transplantation from living donors for children are frequently used all over the world. Despite the difficulties of adequate volume reduction and the age difference between the donor and the recipent, all these techniques also share the problem of size mismatch between the vessels of the adult liver and those of the pediatric recipient. Portal vein reconstruction in a crucial factor for a successful transplantation because it allows blood flow to the liver graft, which ends the ischemic period for the graft, as well as the anhepatic period for the recipient. METHODS: In Group I (n=10, no growth factor), a partial liver of Sprague-Dawley(SD) rat was transplanted heterotopically, via microsurgical technique, to a SD rat with performing end-to-end portal vein anastomosis without applying growth factor to the suture of the portal vein. In Group II (n=10, 50-60% growth factor), a partial liver of a SD rat was transplanted heterotopically to a SD rat, via microsurgical technique, with applying growth factor to 50-60% of the diameter of the portal vein. In Group III (n=10, 80-100% growth factor), the portal vein was anastomosed, via microsurgical technique, with using growth factor to 80-100% of the diameter of the portal vein. RESULTS: In Group II, only one case has portal vein stenosis on the postoperative 14th day following portal vein anastomosis with growth factor. In Group I, 3 cases showed portal vein stenosis on the postoperative 7th day, and 5 cases showed portal vein thrombosis on the postoperative 14th day. In Group III, 6 cases died due to bleeding after declamping of the portal vein anastomosis with using 80-100% growth factor on the diameter and 1 case has portal vein thrombosis on the postoperative 14th day. CONCLUSION: Several surgical factors might have an important role in preventing vascular stenosis and thrombosis, and especially when transplanting a technical-variant liver graft like a reduced-size or split liver graft. To overcome the small caliber of the portal vein and the difference in caliber between the donor and recipient vessels, the growth-factor suture technique having 50-60% of one diameter might be helpful because it allows for expansion along the suture line and it also prevents a purse-string effect.