[Cholestasis and liver dysfunction in critical care patients]

Cornerstones of the diagnostic investigations of disturbances in liver function are analysis and sophisticated evaluation of serum liver enzymes, bilirubin and ammonia. Coagulation factors, serum albumin and cholinesterase levels are indicators of the hepatic metabolic capacity. Dynamic assessment of complex liver functions allows quantification of the hepatic metabolic activity and excretory function. Imaging techniques permit visualization of the size and texture of the liver, the vascular supply and perfusion as well as an assessment of the gall bladder and the extra-hepatic and intra-hepatic bile ducts. Manifold causes for cholestasis and/or liver dysfunction are known, such as ventilation with high pressure, total parenteral nutrition, shock, hypoxia and certain drugs. Obstructive cholestasis requires reconstitution of bile duct drainage, while non-obstructive cholestasis primarily requires treatment of the causative disease. The symptomatic therapy of liver insufficiency is rarely possible via direct treatment of the cause, but mostly requires specific management of secondary organ dysfunctions related to hepatic dysfunction including circulatory failure, hepatorenal syndrome and hepatic encephalopathy. In rare cases a temporary liver surrogate is necessary. The molecular absorbent recirculating system (MARS), a form of extracorporeal albumin dialysis, is introduced as a modality for the treatment of liver failure.