Traumatic brain injury and aeromedical evacuation: when is the brain fit to fly?

BACKGROUND To review the inflammatory sequelae of traumatic brain injury (TBI) and altitude exposure and discuss the potential impact of aeromedical evacuation (AE) on this process. METHODS Literature review and expert opinion regarding the inflammatory effects of TBI and AE. RESULTS Traumatic brain injury has been called the signature injury of the current military conflict. As a result of the increasing incidence of blast injury, TBI is responsible for significant mortality and enduring morbidity in injured soldiers. Common secondary insults resulting from post-traumatic cerebral inflammation are recognized to adversely impact outcome. AE utilizing Critical Care Air Transport Teams has become a standard of care practice following battlefield injury, to quickly and safely transport critically injured soldiers to more sophisticated echelons of care. Exposure to the hypobaric conditions of the AE process may impose an additional physiologic risk on the TBI patient as well as a "second hit" inflammatory stimulus. CONCLUSIONS We review the known inflammatory effects of TBI and altitude exposure and propose that optimizing the post-traumatic inflammatory profile may assist in determining an ideal time to fly for head-injured soldiers.