Emergency Department Observation of Mild Traumatic Brain Injury with Minor Radiographic Findings: Shorter Stays, Less Expensive, and No Increased Risk Compared to Hospital Admission

Objective: The management of mild traumatic brain injury (mTBI) with minor radiographic findings traditionally involves hospital admission for monitoring, although this practice is expensive with unclear benefit. We implemented a protocol to manage these patients in our emergency department observation unit (EDOU), hypothesizing that this pathway was cost effective and not associated with any difference in clinical outcome.

Methods: mTBI patients with minor radiographic findings were managed under the EDOU protocol over a 3-year period from May 1, 2015 to April 30, 2018 (inclusions: ≥19 years old, isolated acute head trauma, normal neurological exam [except transient alteration in consciousness], and a computed tomography [CT] scan of the head with at least 1 of the following: cerebral contusions <1 cm in maximum extent, convexity subarachnoid hemorrhage, or closed, non-displaced skull fractures). These patients were retrospectively analyzed; clinical outcomes and charges were compared to a control cohort of matched mTBI hospital admissions over the preceding 3 years.

Results: Sixty patients were observed in the EDOU over the 3-year period, and 85 patients were identified for the control cohort. There were no differences in rate of radiographic progression, neurological exam change, or surgical intervention, and the overall incidence of hemorrhagic expansion was low in both groups. The EDOU group had a significantly faster time to interval CT scan (Mean Difference (MD) 3.92 hours, [95%CI 1.65, 6.19]), = 0.001), shorter length of stay (MD 0.59 days [95% CI 0.29, 0.89], = 0.001), and lower encounter charges (MD $3428.51 [95%CI 925.60, 5931.42], = 0.008). There were no differences in 30-day re-admission, 30-day mortality, or delayed chronic subdural formation, although there was a high rate of loss to follow-up in both groups.

Conclusions: Compared to hospital admission, observing mTBI patients with minor radiographic findings in the EDOU was associated with significantly shorter time to interval scanning, shorter length of stay, and lower encounter charges, but no difference in observed clinical outcome. The overall risk of hemorrhagic progression in this subset of mTBI was very low. Using this approach can reduce unnecessary admissions while potentially yielding patient care and economic benefits. When designing a protocol, close attention should be given to clear inclusion criteria and a formal mechanism for patient follow-up.