Acute liver failure - Emerging treatments

Non-biological hepatic assist devices

Non-biological hepatic assist devices have been developed as a means of temporary liver support in ALF to bridge patients to a point of recovery or liver transplantation. These devices are based on plasma exchange, haemodialysis, haemofiltration, charcoal haemoperfusion, and resin haemoperfusion systems. The most widely studied is the molecular adsorbent recirculating system (MARS). One randomised controlled trial involving MARS failed to demonstrate a survival benefit in patients with ALF; however, a large proportion of patients in this trial underwent liver transplantation within a short interval from enrolment, precluding definitive safety and efficacy assessment.[125] Although improvements in some physiological parameters have been reported in prospective studies, none of these systems has demonstrated a significant impact on clinical end points or overall survival in the setting of ALF.[126][127][128]

Bioartificial hepatic assist devices

Bioartificial or cell-based hepatic assist devices incorporate hepatocytes or other cell types to provide metabolic as well as detoxification function as a means of temporary liver support in ALF. Cell types used in these devices include immortalised cells such as the C3A human hepatoblastoma cell line or primary porcine hepatocytes. Preliminary studies of bioartificial hepatic assist devices have demonstrated safety; however, their utility or efficacy in the setting of ALF has yet to be determined.[128][129]

Liver tissue engineering and hepatocyte transplantation

Several small studies have demonstrated the ability to transplant human hepatocytes in the setting of ALF; however, further research will be required to achieve optimal viability, function, and preservation of the transplanted hepatocytes. Efforts towards development of hepatocyte culture systems and tissue engineering may provide a source of hepatocytes or liver tissue in the future that could further advance these methods.[7]

Auxiliary transplantation

Auxiliary liver transplantation uses a partial liver allograft to provide temporary support and hepatic function in the setting of ALF, allowing the recipient's native liver to recover function. A partial left hepatic lobe or right hepatic lobe is transplanted from the donor to the recipient. This form of transplantation may benefit younger patients; however, it is associated with a greater incidence of postoperative complications and up to 15% of patients ultimately undergo re-transplantation.[130]