Key points in Critical Care Medicine

Extracorporeal liver support devices in the ICU.

 “Adapted from Oxford Textbook of Critical Care”

• There is an unmet need for a liver support system because of the increasing shortage of organs for transplantation and the complications associated with the procedure.
• In theory, acute liver failure and acute decompensation of chronic liver disease secondary to a precipitating event are potentially reversible. In this context, an extracorporeal liver support can temporarily substitute liver functionality to allow natural recovery through regeneration of hepatocytes and elimination of the precipitating event.
• Goals of liver support system are to provide all functions of the liver, including synthetic and metabolic functions, and to remove as well as reduce the production of pro-inflammatory mediators to attenuate the inflammatory process.
• Currently existing devices are either purely mechanical and/or cell-based. Detoxification is provided by both systems, but biological activities are limited only to the cell- based systems. Albumin dialysis is the major component of mechanical devices because albumin is irreversibly destroyed in liver failure.
• Cell-based or bio-artificial systems are essentially ‘mini-livers’, but their success is limited by the lack of a continuous and abundant supply of high-quality hepatocytes.