Factors contributing to fatal outcome of traumatic brain injury: a pilot case control study

Patients with traumatic brain injury (TBI) have a high mortality and morbidity. This pilot study was undertaken to identify contributors to outcome in the early management of patients with TBI and to investigate the feasibility of a larger study.

Road trauma patients who died between January 1 and April 30, 2000 were selected from the Alfred Hospital's Intensive Care Traumatic Brain Injury database. These patients were matched with 2 survivors from the data base during the same period for age, injury severity score (ISS) and severity of brain injury using the head abbreviated injury score (head AIS). Patient injury scoring (using the revised trauma score, trauma and injury severity score and Glasgow coma score), arterial blood gas analysis, lactate concentration, inspired oxygen concentration, systolic and mean arterial blood pressure, intracranial pressure, intravenous fluid and blood transfusion volumes, body temperature, haemoglobin, white cell count, INR, APTT, temperature and plasma glucose, urea and creatinine concentrations were recorded for 48 hours from the time of injury. Time periods from the accident to key events (e.g. arrival of ambulance at accident scene, intubation, arrival at the emergency department, insertion of intracranial pressure monitor and primary surgery) were also recorded.

Eighteen patients (6 deceased, 12 survivors) were identified. Despite matching, deceased patients had lower initial Glasgow Coma Scores (GCS) (3.6 vs. 7.4, P = 0.01) and lower revised trauma scores (4.41 vs. 5.75; P = 0.044) compared with survivors. There were no significant differences in other parameters. However, deceased patients tended to have longer times to treatment (P = NS) and experienced trauma at night more frequently, and survivors received almost double the volume of fluid resuscitation during the first 12 hours (19.7 +/- 19.1 vs. 11.8 +/- 2.7 mL/kg/hr, P = 0.513).

Both initial GCS and severity of brain injury should be used to match TBI patients for injury severity in future studies. Lower initial GCS in deceased patients was likely due to greater severity of brain injury, although it is also possible that the lower GCS was due to decreased brain perfusion (perhaps reflecting inadequate resuscitation) in these patients. Volume of early fluid resuscitation, time to definitive therapy, and time of presentation to hospital may also be important determinants of patient outcome. A large case control outcome study is required to extend these observations.