A new animal model for split liver transplantation using an infrahepatic IVC graft.

An animal model of split liver transplantation using pigs is described herein. The donor liver was divided into two grafts, the right graft consisting of the right medial and lateral segments with the caudate lobe, and the left graft consisting of the left lateral and medial segments. To make implantation easier, a distal part of the donor's inferior vena cava (IVC) was isolated and attached to the left graft with an anastomosis between the orifice of the renal vein and the graft's hepatic vein. The left graft thereby contained a newly constructed retrohepatic IVC for anastomosis to the recipient. During the anhepatic phase, no conventional bypass procedure was used, but an abdominal aortic clamp in combination with general hypothermia was employed. Ten pigs were used as donors and a total 20 liver transplantations performed. No immunosuppressive drugs were given in this series. Ten of the 20 recipients survived for more than 2 days, the mean survival time being 4.7 days, with a range of 2-14 days. The mean survival time of the left grafts was much longer than that of the right grafts, although no technical problems such as kinking of the graft or occlusion of the hepatic vein were encountered in either. This model is the first report of split liver transplantation in animals. The advantages of using the infrahepatic IVC graft include stability of the graft and safe hepatectomy. This model will therefore be useful for the experimental study of split liver transplantation and may also be employed for clinical use in the future.