Liver support systems: Promise and reality

Effective liver support is needed for a variety of indications. A large number of both biological (containing hepatocytes) and non-biological extracorporeal liver support systems have been described in the literature over the last 50 years. Despite this, there is a paucity of good quality randomized control data examining the effectiveness of these therapies in human liver failure. In this review article, we examine the available data, with particular emphasis on the current front runners, the MARS and HepatAssist systems. Other problems associated with the development of these liver support systems are also discussed. Although promising in animal studies, we conclude that the use of these technologies is not supported currently by a sufficient evidence base to recommend them for routine clinical use and that a lack of understanding about the critical functions required of a liver support system is retarding a more rational approach to the design of these systems.