Prediction of Acute Dysfunction of the Liver after Warm Ischemia

Evaluation of Hepatic Venous Oxygen Saturation as an Indicator

Abstract

Early detection of a poor-functioning hepatic graft is one of the most important issues in liver transplantation and liver surgery, but neither easy or very reliable methods exist. To determine their capabilities to predict early liver function and/or liver graft quality and the resultant postoperative outcome, the hepatic oxygen consumption, hepatic venous oxygen hemoglobin saturation (Shvo₂), arterial ketone body ratio (AKBR) and adenine triphosphate (ATP) levels of hepatic tissue were investigated in warm ischemic models using adult mongrel dogs. In particular information from the Shvo₂ measurement could be derived in both real-time and continuously, if it could be a very reliable liver function test. 60 and/or 90 minutes of warm ischemia of the liver were created by temporarily blocking the hepatic artery and portal vein flow after formation of a porto-venous bypass between the splenic vein and the femoral vein for hemodynamic stability, The results of the hepatic oxygen consumption correlated well with tissue ATP levels and AKBR according to the severity of the warm ischemic damage. Shvo₂ correlated well with the total hepatic flow (hepatic arterial flow plus portal vein flow)(p= 0.011). However, Shvo₂ was not significantly reduced according to the severity of 60 and 90 minutes of warm ischemic damage. Therefore, Shvo₂ would be reliable to predict the decline of the hepatic blood flow, but it could not predict the severity of the warm ischemic parenchymal damage to the liver. The hepatic oxygen consumption, AKBR and/or tissue ATP levels would be a reliable indicator of postoperative liver dysfunction or an indicator of graft quality after liver ischemia and/or transplantation.