Outcome after severe head injury: an analysis of prediction based upon comparison of neural network versus logistic regression analysis.

More reliable prediction of outcome would be helpful for clinicians who treat severely head-injured patients. To determine if neural network modeling would improve outcome prediction compared with standard logistic regression analysis and to determine if data available 24 h after severe head injury allows better prediction than data obtained within 6 h, we tested the ability of both techniques at these two times to predict outcome (dead versus alive) at 6 months. One thousand sixty-six consecutive patients with Glasgow Coma Scale scores of 8 or less during the first 24 h after injury were randomly divided into two groups. Data from the first group (n = 799) were used to develop the models; data from the second group (n = 267) were used to test the accuracy, sensitivity, and specificity of the models by comparing predicted and actual outcomes. The 6-month mortality rate was 63.5%. Our findings confirm the importance of age, Glasgow Coma Scale scores, and hypotension in predicting outcome. Using data available at 24 h improved the predictive power of both models compared with admission data; at both time points, however, the differences in the results obtained with the two models were negligible. We conclude that outcome (dead versus alive) at 6 months after severe head injury can be predicted with logistic regression or neural network models based on data available at 24 h. Critical therapeutic decisions, such as cessation of therapy, should be based on the patient's status 1 day after injury and only rarely on admission status alone.

Severity and outcome of intracranial lesions in pedestrians injured by motor vehicles.

To evaluate the type and severity of intracranial lesions and the prognosis after closed head trauma in pedestrians injured by motor vehicles, we reviewed the cases of 225 consecutive patients who suffered major head injuries in collisions with motor vehicles. Patients in this series were comatose, had intracranial hematomas requiring surgical removal, or both. The initial Glasgow Coma Scale (GCS) score was 9-15 in 24% of patients, 6-8 in 32%, and 3-5 in 43%. Intracranial hypertension occurred in 40%. Diagnostic studies showed subdural hematomas in 45% of patients, epidural hematomas in 8%, intracerebral hematomas in 10%, and cerebral contusions in 9%. Clinically significant mass lesions were evacuated, and intracranial pressure was monitored and treated aggressively if elevated. After 6 months, 51% of the patients had died, 13% were vegetative or severely disabled, and 35% had a good outcome or moderate disability. These major head injuries in pedestrians struck by motor vehicles were usually severe, included a high incidence of intracranial hematomas and increased intracranial pressure, and frequently had poor outcomes.