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ture between donor and recipient suprahepatic IVC first, then the infrahepatic IVC. Prior to completion of the infrahepatic IVC anastomosis, the liver is flushed with 500 cc of cold Ringer's lactate solution until the effluent from the infrahepatic IVC is clear and, at this point, the IVC anastomosis is completed. Next the portal vein anastomosis is performed end-to-end with running non-absorbable monofilament suture leaving a 'growth factor' in order to prevent a narrowing of the anastomosis. In the case of a thrombosed or inadequate portal vein, a donor iliac vein conduit is anastomosed preferably to the confluence of the splenic and superior mesenteric veins (SMV) or alternatively to any patent branch of the portal venous system including the SMV. SMV-to-portal vein grafts are tunneled through the transverse mesocolon. Once the portal vein anastomosis is completed, the clamps are removed in sequence and the liver is thus perfused with portal venous inflow.

Venous-venous bypass (VVP) is occasionally used, prior to completion of the hepatectomy, in order to decompress the splanchnic venous system as well as venous return from the lower extremities. Some centers use VVP routinely, whereas in other centers it is not used at all.18 Most centers use VVP in selected patients, especially when the hepatectomy has been difficult and bloody, or when significant portal hypertensive bleeding is evident especially from the bare area. VVP requires cannulation of both a lower extremity vein, typically the saphenofemoral vein, and an upper extremity or neck vein. This can be achieved either via cut-down or by a percutaneous approach. Partial VVP can also be used, consisting of lower extremity to upper extremity bypass alone, as compared to full VVP which includes a portal venous line in order to decompress the portal vein. The decision to use or not to use VVP may depend on the hemodynamic stability of the recipient upon clamping, especially of the IVC. Rapid infusion can be used to offset some degree of hemodynamic instability during the clamping phase, but if the patient does not tolerate clamping without significant hemodynamic instability, then VVP should be considered.(Table 9.13)

Upon reperfusion of the liver with portal venous inflow, patients can develop a "reperfusion syndrome" consisting of right-sided ventricular failure associated with high filling pressures and systemic hypotension, significant arrhythmias can also occur. This syndrome is usually transient in nature and thought to be secondary to infusion of potassium or acid load from the preserved liver, and from splanchnic and lower extremity venous congestion. Expert anesthetic management and correction of electrolyte abnormalities are needed during this transient period.

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