Background: Liver Failure

The liver is a complex organ with numerous vital functions in synthesis, detoxification and regulation; its failure therefore constitutes a life-threatening condition. Liver failure (LF) can either occur without preceding liver disease (acute liver failure, ALF), usually caused by drug toxicity (in particular, but not exclusively, Paracetamol in overdose) or by acute viral hepatitis, or as decompensation of chronic liver-disease, the most important underlying processes being alcoholic liver disease, obesity-related liver disease (non-alcoholic fatty liver disease (NAFLD)) and chronic viral hepatitis (Hepatitis B & Hepatitis C).

Less common causes of underlying chronic liver disease include inflammatory and immune liver diseases such as primary sclerosing cholangitis and primary biliary cirrhosis, genetic disease such as Wilsons disease and pregnancy-related liver disease. Clinical features include icterus (the flooding of the body by chemicals normally detoxified by the liver), hepatic encephalopathy (the metabolic disturbance of brain function of severity up to and including coma and the development of cerebral oedema) and impairment of coagulation status, and may result in multiple organ failure.

Both acute and chronic liver failure can be effectively treated by liver transplantation with good long-term outcomes. Transplantation as a treatment is, however, significantly limited by the number of donor organs available for the procedure, which does not come close to meeting the existing demand, let alone the increasing demand which is predicted in light of the ongoing steep increases in both acute and chronic liver disease and expanding indications (for example treatment of liver cancer).

One obvious approach to the twin challenges of increasing indications for liver transplantation and the numbers of organs required outstripping supply would be alternative artificial liver support technologies which, although not themselves curative, could provide support to allow the patient to benefit from the liver’s phenomenal capacity to recover naturally, thereby avoiding the need for transplant and preserving a precious resource for use in others.