Artificial liver support systems in the management of complications of cirrhosis

Acute-on-chronic liver failure (ACLF) is associated with multiorgan dysfunction requiring intensive care support and carries an exceptionally high risk of mortality. Decompensation of liver cirrhosis is triggered by different precipitating events but the final common pathway is hypothesized to be unregulated systemic inflammation. The concept of an artificial liver that may impact favorably upon the inflammatory response and provide liver function to prevent complications seems to be promising. This article aims to describe the currently available artificial and bioartificial systems and reviews their effect on different complications of cirrhosis, such as liver function and hepatic hemodynamics, renal function and systemic hemodynamics, hepatic encephalopathy, inflammation/infection, and coagulation. Due to the difficulties in studying large patient numbers with ACLF and the heterogeneity of this patient group, only limited data on survival are available. The currently available studies indicate that there is a survival benefit for artificial and bioartificial liver support in certain subgroups of patients; however, further studies are warranted. At present several studies in this field are under way. In this review several of the companies interested in the manufacture of the respective devices provide an up-to-date report of ongoing trials. In summary, artificial and bioartificial liver support are already playing important roles in the treatment of complications of ACLF. Better understanding of the pathophysiology of ACLF, further development of the current systems, and their evaluation in appropriately controlled clinical studies are necessary to translate their application to improvement in outcome of patients with ACLF.