Emerging concepts in the pathophysiology of traumatic brain injury.

A complex set of molecular and functional reactions is set into motion by traumatic brain injury (TBI). New research that extends beyond pathological effects on neurons suggests a key role for the blood-brain barrier, neurovascular unit, arginine vasopressin, and neuroinflammation in the pathophysiology of TBI. The prevalence of molecular derangements in TBI holds promise for the identification and use of biomarkers to assess severity of injury, determine prognosis, and perhaps direct therapy. Hopefully, improved knowledge of these elements of pathophysiology will provide the mechanistic clues that lead to improved treatment of TBI.