Transient portacaval shunt for a small-for-size graft in living donor liver transplantation

Abstract

Adult-to-adult living donor liver transplantation (AALDLT) is an established treatment option for selected patients with end-stage liver disease. However, its widespread application is limited by the liver volume that can be safely resected from a living donor because a sufficient volume is also required for the recipient. Use of a right lobe graft is widely recommended in AA-LDLT because it can provide sufficient volume to the recipient. However, in comparison with the left lobe graft, the right lobe graft imposes a burden on the donor due to the smaller residual liver volume in the donor. Moreover, the recipient operation with the right lobe graft may be more complicated in consequence of the reconstruction of middle hepatic vein tributaries and plural bile duct. On the other hand, the main problem in using the left lobe graft in AA-LDLT is the small-for-size graft syndrome (SFSGS). The size of the graft required for successful liver transplantation is 30%-40% of the expected liver volume for the recipient or 0.8%-1.0% of the body weight. It is reported that excessive portal venous inflow is a determining factor for injury to endothelial cells and hepatic parenchyma related to SFSGS. A better understanding of the pathophysiology of the small-for-size graft may lead to logical approaches for improving subsequent allograft function. In recent reports, a permanent portacaval (PC) shunt was developed to resolve SFSGS. Partial diversion of the portal flow to the systemic circulation through a PC shunt may be a reasonable approach for attenuating these injuries. However, in this technique, there is every possibility of disturbing appropriate graft regeneration after liver transplantation because a sufficient amount of portal blood does not flow into the graft permanently. In this report, we describe a successful technique for transient PC shunt in small-for-size liver transplantation. A 54-year-old woman with primary biliary cirrhosis underwent LDLT with a left lobe. The actual volume at the back table was 316 ml, which represented 35.8% of the recipient’s estimated standard liver volume. Because the graft volume was small for the recipient, a transient PC shunt was performed between the inferior vena cava and the right branch of the portal vein. To prevent portal hypertension, the PC shunt was performed immediately after total hepatectomy by using a continuous 6-0 Prolene suture. The Endoloop (Ethicon, Somerville, NJ, USA) was passed around the PC shunt beforehand (Fig. 1A). When the graft was implanted, the donor’s hepatic vein was anastomosed to the confluence of the recipient’s middle hepatic vein and left hepatic vein. Subsequently, portal vein anastomosis was performed using a continuous Prolene 6-0 suture. The hepatic vein was then unclamped, and portal reperfusion was initiated. After reperfusion of the portal vein, hepatic artery anastomosis and bile duct reconstruction were performed. After all vascular anastomoses were complete, a 20-French Scale Nelaton tube was inserted into the abdominal cavity. The tip of the tube was located on the PC shunt. The Endoloop was taken out of the abdominal cavity through the tube (Fig. 1B). A hemoclip was fixed on the Endoloop as amarking for the ligation of the Endoloop through a fluoroscope. Another hemoclip was fixed on the opposite side of the Endoloop (Fig. 2). Three-dimensional computed tomography revealed the PC shunt patency 7 days after the operation (Fig. 3). After confirming that the recipient’s clinical condi-