Evaluation of extracorporeal bioartificial liver devices

The initial clinical studies on artificial liver support were performed at King's College Hospital, London during the late 1970s. Initially using charcoal haemoperfusion, and subsequently resin haemoperfusion, and these studies culminated in a controlled clinical trial of charcoal haemoperfusion in which overall survival was high, but no statistically significant benefit was found. From this study, much information was also obtained about the clinical importance of the various complications of acute liver failure, and the experience of King's over the last 2 decades exceeds 1,000 patients. The aim of this article is to review the potential of the exciting new developments in this field of bioartificial liver support incorporating hepatocytes. It focuses on the published findings of early clinical use of these systems and attempts to identify what is needed in further studies. It is of paramount importance that future trials are designed to give the greatest information on the effects of bioartificial liver support. For these, the biocompatibility of the systems should to be confirmed with detailed assessment and sensitive tests need to be developed to determine the metabolic functional efficacy of these devices. The possible relationship of treatment to liver regeneration has been considered, because without this these systems will in many cases be limited to use as a bridge to liver transplantation. Finally, some of the possible future modifications of the cell-based liver support systems are discussed.