Management of traumatic brain injury

The goal of research in traumatic brain injury (TBI) is to identify processes that contribute to mortality and morbidity and that are amenable to intervention. Recent observations that neural loss progresses for weeks to months after TBI suggest a prolonged interval during which interventions could be accomplished. Cell dysfunction and death after TBI are related to a variety of posttraumatic vascular and cellular processes. After TBI, cerebral blood flow progresses through three phases: phase I, decreased cerebral blood flow and cerebral metabolic rate for oxygen; phase II, increased cerebral blood flow with unchanged cerebral metabolic rate for oxygen; and phase III, cerebral vasospasm. In severely head injured patients, impaired cerebrovascular autoregulation correlates with poor outcome. Impaired brain tissue oxygenation after TBI can be measured by intraparenchymal probes that have also been used to define changes in tissue oxygenation in response to pharmacologically increasing cerebral perfusion pressure, mannitol, and hyperventilation.