[Novel magnetic rings for rapid large vascular reconstruction in canine liver transplantation model]

To investigate an improved large vascular reconstruction method in the canine liver transplantation and see whether it can shorten the anheptic time and thus reduce the harmful effects during the anhepatic phase.

Thirty-two mongrel dogs were enrolled and divided into two groups randomly:the donor group (n= 16) and the acceptor group (n = 16). The dogs in the acceptor group were divided into two groups, according to the different reconstruction methods: Group A using the magnetic rings for a large vein reconstruction in the canine liver transplantation (n = 10), and Group B using a hand-sewing large vein reconstruction in the canine liver transplantation (n = 6). The operation time, hemodymics change, anastomosis site, and survival were observed.

The operation time was as follows: In Group A, the total operation time, the inferior vena cava anastomosis time, and the anheptic phase time were significantly shorter than those in Group B (3.24+/-0.49 h vs 4.12+/-0.51 h, 5.89+/-2.27 min vs 28.33+/-6.04 min, 3.89+/-0.73 min vs 12.16+/-3.72 min),with a significant difference between the two groups (P< 0.01). The haemodymics changes were as follows: In Group A, MAP dropped during the anhepatic phase, but it soon recovered after reperfusion, and there was only 730.56+/-150.56 ml of fluid including the donor blood that needed to be transfused, with no pressor agent required. In Group B, blood pressure dropped during the anhepatic phase, but it slowly recovered,and there was 2241.67+/-390.78 ml of fluid. In Group A, all the stomas had no errhysis, twist or thrombus. The twisted stomas could be corrected by the revolving of the magnetic rings. The endangium at the site of anastomosis was smooth. In Group B, most of the stomas had errthysis. In Group A, 3 dogs survived for more than 7 days, 6 dogs survived for 3-6 days, and 1 dog survived for only 12 hours. In Group B, 2 dogs survived for 3-6 days, 3 dogs survived for 1-2 days, and 1 dog survived for only 12 hours.

Using the magnetic rings for a large vascular reconstruction in the canine liver transplantation is an improved method, which can simplify the anastomosis procedures and significantly shorten the anheptic phase time. However, the magnetic rings have to be placed in the abdomen, so this method remains to be further improved.