Liver support systems as perioperative care in liver transplantation-historical perspective and recent progress in Japan.

A meta-analysis of the efficacy of artificial liver support (ALS) systems for fulminant hepatic failure (FHF) by the Cochrane Hepato-Biliary Group suggested that all ALS systems previously developed are ineffective for FHF. This supports the view that the only treatment of choice for FHF is immediate liver transplantation. Plasma exchange, in combination with high-volume hemodiafiltration or high-flow continuous hemodiafiltration using large pore membranes, which was excluded from the Cochrane meta-analysis because of the lack of randomized control trials, has become a standard ALS system in Japan. This system is safe, and it efficiently removes more low and middle molecular weight toxic substances than other methods by using a large volume of buffers (more than 200 L per session), resulting in recovery from coma in patients with severe FHF comparable to an ahepatic state. These artificial liver support systems are effective tools for sustaining patients with FHF in a favorable condition until liver function recovers or liver transplantation becomes available.