Hyperglycemia and neurological outcome in patients with head injury

To examine the relationship between serum glucose and the outcome of patients suffering from head injury, the authors retrospectively reviewed the clinical course of 169 patients admitted for treatment to Harborview Medical Center (a regional trauma center). All patients underwent craniotomy for evacuation of intracranial hematoma and/or placement of a subarachnoid bolt for intracranial pressure monitoring under general anesthesia. Patients with a Glasgow Coma Scale (GCS) score of 8 or less had significantly higher serum glucose levels than patients with GCS scores of 12 to 15 (mean +/- standard error of the mean 192 +/- 7 mg/dl vs. 130 +/- 8 mg/dl or 10.7 +/- 0.4 mmol/liter vs. 7.2 +/- 0.4 mmol/liter) (p less than 0.0001). Patients who subsequently remained in a vegetative state or died had significantly higher glucose levels both on admission and postoperatively than patients who had good outcome or moderate disability (217 +/- 12 mg/dl vs. 167 +/- 6 mg/dl or 12.1 +/- 0.7 mmol/liter vs. 9.3 +/- 0.3 mmol/liter on admission, and 240 +/- 16 mg/dl vs. 156 +/- 5 mg/dl or 13.3 +/- 0.9 mmol/liter vs. 8.9 +/- 0.3 mmol/liter postoperatively) (p less than 0.0001). Among the more severely injured patients (GCS score less than or equal to 8), a serum glucose level greater than 200 mg/dl (11.1 mmol/liter) postoperatively is associated with a significantly worse outcome (p less than 0.01). The authors conclude that severely head-injured patients frequently develop hyperglycemia and the elevated serum glucose level may aggravate ischemic insults and worsen the neurological outcome in such patients.