Abstract
Patients with mild traumatic brain injury (mTBI) with associated intracranial injury, or complicated mTBI, are at risk of deterioration. Clinical management differs within and between institutions. We conducted an exploratory analysis to determine which of these patients are unlikely to have an adverse outcome and may be future targets for less resource intensive care. This single center retrospective cohort study included patients presenting to the ED with blunt complicated mTBI between January 2001 and December 2010. Patients with a Glasgow coma score (GCS) of 15, an initial head CT with a traumatic abnormality, and a repeat head CT within 24h were eligible. We defined the composite adverse outcome as death within two weeks, neurosurgical procedure within two weeks, hospitalization >48h, and worsened second head CT. Classification and Regression Tree methodology was used to identify factors associated with adverse outcomes. Of 1011 patients with two head CTs performed in a 24-h period, 240 (24%) had complicated mTBI and GCS 15. Of these, 56 (23%) experienced the composite adverse outcome defined above. Age, headache, and subarachnoid hemorrhage, correctly classified 93% of patients with an adverse outcome. No instance of death or neurosurgical procedure was missed. Our analysis highlighted three factors associated with adverse outcomes in persons who have complicated mTBI but a GCS of 15. Absence of these risk factors suggests low risk of adverse outcomes, and may suggest that a patient is safe for discharge home. Additional research is required before utilizing these findings in clinical practice.