Perfusion Dynamics for Extracorporeal Hepatic Assist

LIVER perfusion during extracorporeal hepatic assist1is best performed with a minimum flow and the simplest possible circuitry. It is, therefore, of both theoretical and practical importance to determine the combination of perfusion dynamics that will achieve such function in the isolated liver. This is a systematic study of factors that thus affect function of the liver perfused with totally oxygenated blood. The liver in vivo is subject to a complex perfusion system that cannot easily be duplicated in detail. Weighing 1,500 gm in man, it is perfused with pulsatile hepatic arterial blood at a rate of 0.32 cc/gm of liver per minute,2and twice3this volume, or 0.65 cc/gm of liver per minute, of portal venous blood of enteric origin.4Oxygen saturation of the portal venous blood varies between 86% and 95%.5The maximum oxygen utilization of normal liver tissue is 2.2 to 2.7