Nutritional support in severe brain injury

Objective Our objective was to present the literature data about the nutritional support of patients with severe brain injury: features of the metabolic response, energy and protein requirements, timing and routes of feeding, the influence of the nutritional support on the course and outcome of the disease. Results Brain injury activates the body’s metabolic and catabolic responses. The loss of nitrogen in a non-feeding head-injured patient can result in weight reduction by 15% per week. The A level evidence suggests that non-feeding of headinjured patients in the first week increases the mortality rate. Early feeding of such patients improves the outcome. The B level evidence shows that replacing 140% of resting metabolic expenditure in non-paralyzed and 100% of resting metabolic expenditure in paralyzed patients, and also 15–20% protein calories can reduce the protein loss. It is a guideline that full energy and nutritional replacement should be instituted by day 7. If there are no any contraindications, enteral feeding is preferred, and the parenteral way is used as supplemental for the replacement of the full energy demand. Gastric emptying is often altered in such patients, thus intrajejunal feeding is recommended with the continuous regimen-feeding pump. A standard enteral formula should be used, with 15–20% of calories as protein. Feeding tolerance, laboratory data and feeding adequacy should be evaluated. Conclusions Early and adequate nutritional support is strongly indicated for the correction of the metabolic response in headinjured patients: 100–140% of resting metabolism expenditure must be replaced with 15–20% of calories as protein. The feeding must be started as early as possible; full energy and nutritional replacement should be instituted by day 7. Early feeding may be associated with better outcomes in terms of infective complications, mortality and disability. But there are no sufficient data how early the full energy and nutritional requirement must be replaced, and how the different types of nutritional support influence the mortality, disability, the incidence of infectional complications and the length of hospital stay