The influence of hyperglycemia on neurological outcome in patients with severe head injury

Traumatic brain injury is associated with a stress response that includes hyperglycemia, which has been shown to worsen neurological outcome during cerebral ischemia and hypoxia. To better examine the relationship between hyperglycemia and outcome after head injury, we studied the clinical course of 267 head-injured patients who were admitted for treatment in the neurosurgical department of Asclepeion Hospital of Athens between January 1993 and November 1997.

We prospectively studied 267 patients with moderate or severe craniocerebral injury (Glasgow Coma Scale scores, 3-12) who were treated surgically for evacuation of an intracranial hematoma and/or placement of a device for intracranial pressure monitoring under general anesthesia to determine the relationship between serum glucose levels, severity of injury, and neurological outcome.

Patients with severe head injury had significantly higher serum glucose levels than did those with moderate injury. Patients who subsequently had an unfavorable outcome had significantly higher glucose levels than did those with a better prognosis. Among the patients with more severe head injury, a glucose level greater than 200 mg/dl was associated with a worse outcome. In the same group of patients, a significant relationship was found between postoperative glucose levels, pupillary reaction, and maximum intracranial pressure during the first 24 hours. Multivariate analysis showed that postoperative glucose levels were an independent predictor of outcome.

Early hyperglycemia is a frequent component of the stress response to head injury, a significant indicator of its severity, and a reliable predictor of outcome.