BACKGROUND: In this era of cost containment, the value of routine repeat head computed tomography (CT) in patients with mild TBI (mTBI) and no interval neurologic change has been challenged. The purpose of this study was to test the hypothesis that routine repeat head CT provides critical information after mTBI even with no neurologic change.
METHODS: From January 1996 to May 2010, records from all patients admitted to our Level I trauma center with an arrival Glasgow Coma Scale (GCS) score of 13 to 15 and at least one head CT were retrospectively reviewed.
RESULTS: In 360 patients with mTBI and positive initial head CT finding, the most common abnormalities were subarachnoid hemorrhage (64%), intraparenchymal hemorrhage (57%), and subdural hemorrhage (40%). Scans were repeated in 8 ± 6 hours; 11% were recalled, 59% remained stable, but 30% showed injury progression. Those patients with worsening repeat head CT finding had higher Injury Severity Score (ISS), were more likely to be intubated and require craniotomy, had longer stay, and had higher mortality (all p < 0.001). On multiple logistic regression, altered GCS score (odds ratio, 3.1–4.0), ISS (odds ratio, 1.1), and presence of mass effect (odds ratio, 2.0) were independently associated with worsening repeat head CT finding. In patients receiving a neurosurgical operative intervention, 32% to 59% had no clinical decline before the worsening repeat CT finding.
CONCLUSION: After mTBI, worsening of repeat head CT finding is seen in a third of patients and is associated with worse outcomes. A substantial fraction of patients who require operative intervention will have no clinical changes in the first 8 hours, supporting the value of repeat head CT within this time frame.
LEVEL OF EVIDENCE: Care management study, level III.