[Artificial nutrition in liver failure].
Nutritional and metabolic support in patients with liver failure should be able to adequately provide the nutritional requirements and, at the same time, to contribute in patients' recovery by controlling or reverting the metabolic impairments observed. However, in spite of the pathophysiologic basis described by some authors considering amino acids unbalance as a triggering and maintaining factor for encephalopathy, there are no sufficient data to recommend the use of "specific" solutions (branched amino acids-enriched and low on aromatic amino acids) as part of the nutritional support of patients with acute liver failure. Its routinary use is neither recommended for preventing complications in patients submitted to liver transplantation. As with other critically ill patients, the nutrients administration route should be the enteral route, whenever possible. The use of "liver failure" specific diets is not recommended; on the contrary, nutrients composition must be adapted to the metabolic stress condition. In patients requiring parenteral nutrition, there is no contraindication to the use of lipid infusions. An increase in vitamins and micronutrients intake is recommended. In patients submitted to liver transplantation, nutrients intake should be started early in the postoperative period through a transpyloric route of access.