ABSTRACT
The liver is a complex organ with multiple functions and as such plays a key role in homeostasis; its importance is best illustrated in acute liver failure. The liver acinus is divided into zones 1–3. The portal triad is composed of the hepatic artery, portal vein and bile duct. It is the portal triad that forms the centre of the acinus and, as such, forms zone 1. Blood becomes progressively poorer in oxygen and nutrients from zone 1 to zone 3. Capacitance function: at any one time the liver can hold as much as 15% of the circulating volume and therefore can act as a large blood reservoir. Serum albumin is difficult to interpret in the setting of critical illness because of renal and gastrointestinal losses; however, it will be reduced in chronic liver disease.
