Anesthesia and head trauma.

Anesthetic care for patients with traumatic brain injury involves an integration of cerebral resuscitation, resuscitation of other vital organs, the provision of "anesthesia," and the prevention of harmful physiologic responses to surgery. Adverse responses to surgery such as hypertension, tachycardia, coughing, and straining can increase intracranial pressure (ICP). Airway manipulations can aggravate spinal cord injury as well as increase ICP. Anesthetic agents can exacerbate hemodynamic instability, increase cerebral blood volume and ICP, and produce respiratory depression. Cerebral resuscitation during surgery resembles that in the preoperative and postoperative periods. ICP measurement and jugular venous saturation monitoring may help define end-points for cerebral resuscitation. Various anesthetic techniques and agents have distinct advantages and disadvantages. The choice of agents and techniques is determined by the nature and severity of the patient's injuries and by pre-existing medical problems. The investigation of drugs that might protect against cerebral ischemia has included anesthetic agents but none appear to be uniformly effective. Intraoperative hypothermia is also being investigated as a cerebral protectant.