[Artificial liver support systems: state of the art]

Previous attempts in improving the outcome of acute liver failure patients were based on extracorporeal artificial systems such as hemodialysis, hemoperfusion, plasmaperfusion, hemoadsorbtion and plasma exchange. Despite more than 30 years of research and development in this field, an artificial liver has still not become a reality, since purely artificial support systems have shown only minor improvement in patient's survival, and orthotopic liver transplantation is the only effective cure. This review takes a critical look at past and present concepts for an artificial liver support system, evaluating the advantages and disadvantages of the aforementioned techniques. Progress in methods and techniques for maintaining long-term hepatocyte culture in vitro indicate the potential use of isolated liver cells in bioartificial liver support systems. Recent studies suggest the use of traditional artificial liver support systems, such as hemoadsorbtion or plasma-absorbtion on activated charcoal particles or synthetic ion-exchange or neutral resins to improve and prolong the efficiency of the so-called hybrid or bioartificial liver, in which isolated hepatocytes are used.