Indications for routine repeat head computed tomography (CT) stratified by severity of traumatic brain injury

BACKGROUND: Controversy exists as to the role of a routine repeat head computed tomography (CT) for patients with traumatic brain injury and an initially abnormal head CT. The specific aim of this study is to identify patients with head injuries who would benefit from a routine repeat head CT. METHODS: This was a 2-year (2003 and 2004) prospective study of all patients with blunt trauma admitted to an urban, Level I trauma center that presented with an abnormal head CT. Results of initial head CT and indications for repeat head CT (routine vs. neurologic change) were recorded. Interventions were both medical (diuresis, hyperventilation, barbiturates) and surgical (intracranial pressure monitor placement or craniotomy). Patients were categorized by Glasgow Coma Scale (GCS) score as having mild (GCS 13-15), moderate (GCS 9-12), or severe (GCS ≤ 8) head injury. RESULTS: There were 354 patients admitted with an initially abnormal head CT. The 37 (10%) patients who went directly to craniotomy and the 43 (12%) patients who died within 24 hours of admission were excluded from analysis. The remaining 274 patients (44 years old, 70% male, mean injury severity score = 19, mean GCS = 10) are the focus of this analysis. After admission, 163 patients underwent a total of 241 repeat CT scans. Of the repeat scans obtained, 102 scans (43%) were unchanged, 54 scans (22%) were better, and 85 scans (35%) were worse. Neurologic deterioration prompted 45 repeat scans (19%), and 196 repeat scans (81%) were obtained routinely after admission without change in neurologic status. The 45 CT scans obtained for neurologic change led to medical or surgical intervention in 38% (n = 17) of cases, whereas scans obtained led to an intervention in only two patients (1%). Both patients who underwent an intervention after a routine scan had a GCS score ≤8 at admission and at the time of routine repeat head CT. One patient had an intracranial pressure monitor placed and the other was taken for craniotomy. No patient with a mild or moderate traumatic brain injury underwent an intervention after a routine repeat head CT. CONCLUSIONS: Patients with any head injury (mild, moderate, or severe) should undergo a repeat head CT after neurologic deterioration, because it leads to intervention in over one-third of patients. Routine repeat head CT is indicated for patients with a GCS score ≤8, as results might lead to intervention without neurologic change.