During liver transplantation, reperfusion traditionally is performed through the portal vein. After anecdotal observations that patients who underwent reperfusion first through the hepatic artery were more hemodynamically stable, we performed an exploratory, prospective, observational, nonrandomized study to compare cardiovascular stability, acid-base status, and metabolic gas exchange between patients who underwent reperfusion through either the portal vein or hepatic artery. We studied 20 patients undergoing liver transplantation (10 patients, reperfusion first through the portal vein; 10 patients, reperfusion first through the hepatic artery). Cardiovascular and acid-base parameters were compared at times before and after anastomosis of each vessel, and epinephrine use was recorded. Oxygen consumption (VO,) and carbon dioxide elimination (VCO,) were measured continuously by using an indirect calorimeter. Alanine aminotransferase (WT) concentrations 24 hours after transplantation were compared as an index of reperfusion injury. Cardiovascular changes (mean arterial pressure, cardiac output) were similar for both groups, but more epinephrine was administered to the portal-vein group (P = .014). There was a greater increase in Paco, after portal reperfusion (median portal vein, 1.01 m a ; hepatic artery, 0.29 Wa; P = ,015) and a trend toward more severe acidemia. Vo, increased more rapidly in the portalvein group (P = .005), but overall changes in VO, during the study period were similar. There were no differences in Vco, between the groups or ALT concentrations 24 hours posttransplantation. These observational data suggest that hepatic arterial reperfusion may be associated with reduced epinephrine requirements and a slower rate of acid release, which could be advantageous in unstable patients. VO, increases more slowly after hepatic artery reperfusion, which could indicate slower reoxygenation of the graft.
537-544.)D uring liver transplantation, the period of greatest patient instability is often after graft reperfusion. Reperfusion can affect patients through two processes that can be considered immediate and delayed. Immediate effects include alterations in cardiovascular, metabolic, and acid-base states that occur within minutes of vascular reperfusion. Delayed effects may not be apparent for 24 to 48 hours and result from reperfusion injury to the graft itself.' Reperfusion injury is initiated at the time of vascular reperfusion and characterized by endothelial and Kupffer's cell injury in hepatic sinuLiver Transplantation, Vol8, soids, reduction in blood flow through these vessels, and hepatocyte damage.2 Ischemia-reperfusion injury can result in significant graft dysfunction in the postoperative period.The ideal technique for graft reperfusion should minimize both immediate and delayed complications. Reperfusion usually is performed through the portal vein as soon as this anastomosis is complete, followed by the hepatic artery. The origin of this practice appears to be largely historical, originating f...