August 1996

Posttraumatic Amnesia as a Predictor of Outcome After Severe Closed Head InjuryProspective Assessment

Author Affiliations

From Westat Inc, Rockville, Md (Dr Ellenberg); and the Division of Neurosurgery, University of Maryland, Baltimore (Dr Levin). Ms Saydjari is a private consultant in Crawfordsville, Ind. Dr Levin is now with the Department of Physical Medicine and Rehabilitation, Baylor College of Medicine, Houston, Tex.

Arch Neurol. 1996;53(8):782-791. doi:10.1001/archneur.1996.00550080104018

Objectives:  To identify the demographic and clinical variables related to the duration of posttraumatic amnesia after severe closed head injury; to evaluate the usefulness of posttraumatic amnesia duration in predicting outcome at the time of hospital discharge and at 6 months after injury.

Setting:  Four clinical centers located in primary care hospitals.

Patients:  Three hundred fourteen severely injured subjects aged 16 years or older who did not have trauma as a result of a penetrating injury and came out of coma before hospital discharge.

Interventions:  Approximately half of the subjects were administered phenytoin sodium for some period after termination of coma; 17% were administered dexamethasone and 41% morphine sulfate.

Main Outcome Measures:  Galveston Orientation and Amnesia Test scores defined the duration of posttraumatic amnesia. The Glasgow Outcome Scale was used to grade outcome at the time of hospital discharge and at 6 months.

Results:  Older age, low initial Glasgow Coma Scale score, nonreactive pupil(s), coma duration, and use of phenytoin were associated with a longer duration of posttraumatic amnesia. Poor pupillary response, time in coma, and duration of posttraumatic amnesia and use of phenytoin was predictive of the 6-month outcome.

Conclusions:  The results support the prognostic usefulness of prospectively measuring duration of posttraumatic amnesia after termination of coma. Pending replication, our findings suggest that posttraumatic amnesia duration may be a useful surrogate outcome measure for clinical trials involving interventions for acute head injury.