Page 383 - Libro 2

23 — Evaluation of Kidney and Liver Transplants
363
Inferior vena cava Liver
helps prevent the development of postsurgical steno- sis at the hepatic artery anastomosis. If the donor or recipient vessels are diseased, the surgeon may use the donor’s iliac vessels to patch or bypass part of a stenotic vessel. When evaluating the vessels, one should remember that there are several anatomic variations of the hepatic arterial system, and the course that the artery takes may not necessarily be the expected one. Complete evaluation of the hepatic artery may require a great deal of scanning and nu- merous acoustic windows.
The portal vein is typically anastomosed in an end-to-end fashion between the donor and the re- cipient main portal vein. If the donor’s portal vein is scarred or thrombosed, a venous “jump” graft will have to be created to bypass the thrombus. The IVC may be “interposed” following resection of the do- nor IVC, requiring both a suprahepatic and infrahe- patic end-to-end IVC anastomosis. However, in many centers, a “piggyback” technique is now preferred that leaves the recipient’s IVC in place, attaching the suprahepatic donor IVC to the recipient’s hepatic confluence (Figs. 23-28 and 23-29).
Single-lobe LRD transplants have become more common in recent years. The donor usually heals easily, as the liver is one of the few organs that can regenerate quickly. The adult donor provides the right portion of his or her liver to an adult recipient and the left portion to a child. The donated right liver will have a right hepatic vein, a right portal vein, a right hepatic artery, and the right hepatic bile duct.
Hepatic artery Portal vein Common bile duct
Figure 23-27 A diagram demonstrating the most common surgical anatomy following orthotopic liver transplantation with an interposition IVC graft.
and the common bile duct (CBD) in an OLT are anas- tomosed in an end-to-end fashion. During the OLT, once it is decided that the liver is suitable for dona- tion, the organ procurement team will harvest the whole liver from a DD including the extrahepatic vessels and CBD. The liver is transported to the re- cipient on ice in a preservative solution. The implan- tation team then removes the recipient’s native liver and gallbladder, called the anhepatic phase. The donor’s CBD is preferentially anastomosed to the recipient’s common hepatic duct in an end-to-end fashion. If the recipient’s common hepatic duct is deformed or diseased, a choledochojejunostomy will be created, whereby the biliary system will drain di- rectly into the jejunum. The choledochojejunostomy is usually made by the Roux-en-Y (i.e., end-to-side) surgical method. The biliary anastomosis is some- times reinforced with a stent that can be seen so- nographically as a linear echogenic structure in the vicinity of the proximal bile duct.
The arterial anastomosis is usually made between the donor’s common hepatic artery or celiac artery and the recipient’s common hepatic artery where it branches into the right and left hepatic artery or the common hepatic artery at the level of the gas- troduodenal artery. The hepatic arterial anastomosis is created with a “fish mouth” technique, whereby the smaller vessel’s walls are split and sewn over the larger, usually the donor, vessel. This technique
Hepatic venous confluence Donor IVC
Liver
Recipient IVC
Figure 23-28 A diagram demonstrating the piggyback tech- nique for performing an IVC anastomosis. (Reprinted with permission from Pellerito JS, Polak JF, ed. Introduction to Vascular Ultrasonography. 6th ed. Philadelphia, PA: Elsevier Saunders. In press.)