Energy, Trace Element And Vitamin Requirements in Major Burns

Nutritional management of patients with severe burn injuries remains a challenge for the clinician. Energy requirements are increased for prolonged periods of time. Substrate flux is accelerated. Catabolism is strongly enhanced, resulting in the loss of lean body mass: full nutritional support is unable to reverse this process. Increasing protein and carbohydrate intakes above respectively 1.3 g/kg/d and 4 mg/kg/min has no proven metabolic benefit. On the contrary, high intakes of carbohydrates and prolonged hypernutrition result in increased de novo lipogenesis, with the risk of developing liver complications like fatty liver infiltration. Strategies to reduce energy expenditure have been developed including early surgery, warm environment, pharmacological treatments (beta-blockade). Trace element and vitamin needs are also strongly increased. The micronutrients have particularly important antioxidant functions after major burns: they contribute to the reduction of lipid peroxidation, to the immune defence, and are essential in most anabolic pathways. There are strongly increased requirements for copper, selenium, zinc, alpha-tocopherol and ascorbic acid. The optimal route for nutrition is the gut, gastric and postpyloric accesses being possible. Enteral nutrition should be used first, and started during the first 24 hours of injury, but parenteral nutrition should not be excluded in patients intolerant to this feeding mode.