THE USE OF HYPERVENTILATION AND ITS IMPACT ON CEREBRAL-ISCHEMIA IN THE TREATMENT OF TRAUMATIC BRAIN INJURY

Traumatic brain injury is a common occurrence in the United States, le ading to approximately 190,000 deaths or long-term disabilities. Follo wing the primary insult, secondary disturbances in cerebral blood now (CBF) and metabolism may have deleterious effects on potentially viabl e neurons. Recent studies evaluating CBF immediately following head in jury have revealed flows low enough to produce cerebral ischemia. Hype rventilation is used routinely to lower suspected increased intracrani al pressure (ICP). Aggressive hyperventilation produces a marked reduc tion in CBF, which may give rise to or exacerbate cerebral ischemia, t hus enhancing rather than reducing secondary injury. This article revi ews the role of hyperventilation in the treatment of increased ICP and its impact on cerebral ischemia following traumatic brain injury.