Metabolism and nutrition in patients with moderate and severe traumatic brain injury: A systematic review

PRIMARY OBJECTIVE: To examine the evidence on the metabolic state and nutritional treatment of patients with moderate-to-severe traumatic brain injury (TBI). RESEARCH DESIGN: A systematic review of the literature. METHODS AND PROCEDURES: From 1547 citations, 232 articles were identified and retrieved for text screening. Thirty-six studies fulfilled the criteria and 30 were accepted for data extraction. MAIN OUTCOMES AND RESULTS: Variations in measurement methods and definitions of metabolic abnormalities hampered comparison of studies. However, consistent data demonstrated increased metabolic rate (96-160% of the predicted values), of hypercatabolism (-3 to -16 g N per day) and of upper gastrointestinal intolerance in the majority of the patients during the first 2 weeks after injury. Data also indicated a tendency towards less morbidity and mortality in early fed patients. CONCLUSIONS: The impact of timing, content and ways of administration of nutritional support on neurological outcome after TBI remains to be demonstrated.