Acute hepatic failure (AHF) with Stage 4 coma is a serious illness with over 60% mortality when treated with supportive therapy. The BioLogic-DT is an extracorporeal liver support device which uses the membranes of a cellulosic plate dialyzes to propel blood through a single access and circulates a suspension of powdered charcoal and cation exchanger sorbents through the dialysate spaces. This device effectively removes dialyzable organic toxin of 100-300 m.w. but is mostly ineffective in removing protein-bound toxins. Nonetheless, over 80% of liver failure patients improve physiologically and neurologically during treatment with the device; most recover liver function often proceed to liver transplant. In the current study, we will place an albumin-permeable hollow-fiber plasmafilter downstream from the plate dialyzed and use the alternating pressure of the blood to drive plasma filtrate (with albumin) into the sorbent suspension (where interaction with charcoal will remove toxins), then return the albumin to the blood. In vitro studies will determine the clearance rate of the system for albumin-bound substances such as bromsulphthalein (BSP), bilirubin, phenol, and tricyclic drugs, and the clearance for non-albumin-bound substances such as creatinine and ammonium. If warranted, Phase II clinical studies will determine whether the new chemical functions of the sorbent improve the treatment of patients with hepatic coma.National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)