Introduction

After cardiothoracic surgery, a mild elevation in the serum concentration of liver enzymes is not uncommon. It is usually transient with little or no clinical sequelae. In contrast, acute hepatic failure is a rare but serious complication. It is associated with multiorgan dysfunction syndrome and carries a poor prognosis.

Functions of the liver

The liver is the largest solid organ in the body. It receives oxygenated blood via the hepatic artery and nutrient-rich blood from the portal vein. The liver performs a variety of important functions.

Carbohydrates in the diet are converted to hexoses and transported to the liver via the portal veins. Glucose enters hepatocytes passively, where it is converted to glycogen. Maintenance of blood glucose concentrations within narrow limits is regulated by insulin and glucagon. Amino acids removed from the blood are utilized for protein synthesis and gluconeogenesis. Approximately 10 to 20 g of albumin is synthesized per day, depending on nutritional status and endocrine balance. The degradation of amino acids leads to nitrogenous waste, in the form of ammonia, which is then converted to urea.

The vitamin K-dependent clotting factors (II, VII, IX and X) are formed in the liver. Other important synthesized proteins include α- and β-globulins, fibrinogen, antithrombin III, α1 acid glycoprotein, haptoglobin and C-reactive protein.

Short-chain fatty acids undergo oxidation in the liver, with the production of ketones and acetoacetate.