Answer to Question 1
A supplementation regimen specifically for TBI has not been established. But since TBI patients are considered to be patients who are not only critically ill but are some of the most hypercatabolic and hypermetabolic, using the critical care guidelines for these patients is appropriate. The ASPEN and SCCM guidelines for adults state that administration of a combination of antioxidant vitamins and trace minerals (specifically including selenium) has been demonstrated to result in reduced mortality. Glutamine has also been recommended for use in burn and trauma patients and may be beneficial for TBI patients as well.
Answer to Question 2
According to ASPEN guidelines for nutrition in the critically ill (2009), enteral nutrition should be initiated within the first 48 hours of admission and is the preferred route over parenteral nutrition. If enteral nutrition alone is not meeting energy requirements after 7-10 days, then parenteral nutrition should be considered. Early enteral nutrition blunts the metabolic stress response, maintains gut integrity, and prevents translocation of bacteria. It has been observed that TBI patients that are not aggressively supported nutritionally have been estimated to lose as much as 15 of their body weight within one week. With potential issues for dysphagia and chewing difficulties coupled with the hypermetabolic needs of the patient, immediate nutrition support is strongly recommended.