[Effect of postoperative complications on nutritional status: therapeutic consequences]

The occurrence of a postoperative complication represents an additional stress factor for patients and leads in many cases rapidly to a malnutrition status. Thus a nutritional support is required as soon as the foreseeable duration of starvation has a longer duration than one week. Considering its lower risk of septic complications and lower cost, enteral feeding should be initiated as soon as possible. Appraisal of caloric needs with standard formulas often leads to inappropriate nutritional management. Therefore the requirements should be assessed by indirect calorimetry if available. Nutritional support is a part of the management of a postoperative septic patient. It must be initiated when initial phase of haemodynamic instability is amended. Branched chain amino acids, medium chain triglycerides and other specific nutrients have failed to demonstrate a real clinical beneficial effect. In case of acute respiratory failure, nutritional support must be cautious with regard to caloric load, as carbohydrates may increase CO2 production and lipids may worsen hypoxaemia. In case of postoperative acute renal failure, nutritional management is facilitated by continuous haemofiltration techniques allowing an unlimited nutrient intake. Solutions containing only essential amino acids are not recommended. During severe acute pancreatitis, enteral feeding is indicated when ileus does not permit the use of the intestinal tract. Jejunal access must be preferred to stomach or duodenum. Lipid emulsions can be used safely if serum triglyceride concentrations remain below 4 g.L-1 during infusion and below 2 g.L-1 between infusions.