Adult-to-adult right lobe living donor liver transplantation (LDLT) is an established procedure and is performed in many centers across the world. It is now well recognized that it is important to provide optimal venous outflow to the right anterior sector of the liver (segments V and VIII) in order to prevent venous congestion of this portion of the graft and to increase the functional graft volume for the recipient.
There are a number of techniques that have been described for reconstructing venous outflow in patients undergoing right lobe LDLT. Although some centers advocate venoplasty of the right hepatic vein (RHV) and the middle hepatic vein (MHV) into a common venous channel, which is then anastomosed directly to a newly created opening on the anterior wall of the inferior vena cava (IVC), others use a variety of extension grafts on the veins draining segments V and VIII, which are then anastomosed to the IVC.[3, 4] We use the MHV stump or a length of the MHV from the recipient's liver and perform a direct anastomosis with the MHV of the graft without the use of any extension. We report this technique for anterior sector venous outflow reconstruction, which we have successfully employed at our institution for 78 right lobe LDLT procedures.
From November 2009 to June 2012, 102 patients underwent right lobe LDLT at our institution. Seventy-eight of these patients underwent a direct MHV-to-MHV anastomosis. The study had received approval from our institutional review committee.
The donor operation was performed according to a technique described by other groups in earlier publications. In brief, after hilar dissection and mobilization of the right lobe, the liver was transected with a Cavitron ultrasonic surgical aspirator (CUSA EXcel, Integra Lifesciences Corp., Plainsboro, NJ) along the plane of Cantlie's line. The RHV was divided at its insertion into the IVC. The MHV was divided as low as possible after adequate drainage to segment IVa of the donor's liver was ensured. If there was no major segment IVa branch draining into the MHV or there was a fissural vein draining into the left hepatic vein (LHV), the MHV was divided as close as possible to its insertion into the IVC or LHV.
The recipient hepatectomy was performed with a technique described elsewhere; care was taken to obtain as much length as possible for the remnant hepatic artery, portal vein, and bile duct. In addition, the hepatic veins were divided high into the liver, and as much length as possible was obtained for the MHV. When the donor's MHV had to be divided proximally to a segment IVa vein, an additional length of the recipient's MHV was carefully dissected from the liver during hepatectomy except for patients with hepatocellular carcinoma (Figs. 1 and 2).
A Satinsky side clamp was applied to the stumps of the RHV and the common stump of the MHV and LHV. No patient underwent cross-clamping of the IVC. Venovenous bypass was infrequently used during the initial part of the program. The RHV of the graft was anastomosed to the RHV stump of the recipient with 4-0 Prolene. The Satinsky clamp on the MHV was applied in a longitudinal manner parallel to the IVC. The graft MHV was then directly anastomosed to the recipient's MHV with 5-0 Prolene in a continuous, single layer to ensure that there was no redundancy in the vein (Figs. 3 and 4). The portal vein and hepatic artery anastomoses were performed in the usual manner. After reperfusion, all patients underwent Doppler ultrasound imaging to document flows within the liver. All patients had an optimal triphasic flow in the RHV as well as the MHV anastomosis. The patients also underwent Doppler ultrasonography on alternate days in the first postoperative week, and adequate flows in all anastomoses were documented.
The MHV is a subject of significant discussion in adult right lobe LDLT. Although some centers advocate the routine inclusion of the MHV in a right lobe graft, others never include the main trunk of the MHV and routinely reconstruct the venous drainage for segments V and VIII with extension grafts. However, others stay well to the right of the MHV during the donor hepatectomy and do not reconstruct the venous drainage to segments V and VIII at all.
There are a number of different techniques for the anastomosis of the MHV, and there is also variation in the site of the venous anastomosis. Many centers make a fresh opening in the IVC for the MHV anastomosis. A Hong Kong group combines the RHV and the MHV into a common outlet by venoplasty and anastomoses this to an extended RHV opening on the IVC. Some centers cross-clamp the IVC in every case in order to facilitate the venous anastomosis. In particular, the technique described by the Hong Kong group necessitates cross-clamping of the IVC. We believe that the avoidance of cross-clamping ensures adequate venous return at all times and protects renal function. Our technique can achieve optimal flow in the MHV without the need for any cross-clamping of the IVC.
It has also been suggested that the MHV stump on the recipient's side should not be used to anastomose the graft MHV because this might result in kinking and obstruction of the anastomosis after the liver has undergone regeneration. However, in our experience, this has not been found to be the case. We believe that the longitudinal orientation of the MHV stump before anastomosis ensures proper alignment with the graft MHV and facilitates an easy anastomosis. The absence of any redundancy ensures that the anastomotic orifice remains open at all times even after regeneration and potential rotation of the right graft.