362 Head Computed Tomography Utilization for Mild Trauma in an Academic Medical Center Emergency Department

Abstract

Noncontrast head computer tomography (NCHCT) is not infrequently performed in emergency department (ED) patients with mild head trauma to evaluate potential intracranial injury. Validated risk assessment tools can safely determine thresholds for imaging. We explored potentially avoidable NCHCTs in patients with closed head injury. We performed a retrospective observational utilization review of all patients aged 16 to 64, inclusive, who were triaged to the low acuity team and underwent auto-protocoled NCHCT for trauma between April 2018 and March 2019 at a single ED site with over 80,000 patient visits per year. The low acuity team was chosen as it was hypothesized that in this population there would be lower compliance with a validated clinical decision rule, specifically the Canadian CT Head Rule (CCTHR), and thus it represented the greatest opportunity for improvement. Mild trauma was defined as a patient with a head injury, a Glasgow Coma Scale (GCS) score of 13-15 and at least one of the following: loss of consciousness, amnesia, or disorientation. Exclusion criteria were atraumatic indication for NCHCT, greater than 24 hours between trauma and presentation, use of anticoagulants or antiplatelet agents, post-traumatic seizure, GCS <13, and inability to score the patient due to incomplete chart information. CCTHR was scored via manual chart review. Patients scoring >0 were deemed to warrant CT imaging. Additional data collected included ordering provider status (physician vs. physician assistant), additional CT imaging, documentation of recommendation for NCHCT by outside providers prior to ED presentation, and any provider acknowledgment that the patient did not meet imaging criteria but was undergoing NCHCT at the patient’s request. Analysis between groups was performed using a Chi-squared test with significance set at p<.05. Over the evaluation time period, 186 NCHCTs were performed by the low acuity team. 165 patients had mild trauma, none of whom had any acute traumatic intracranial findings. 64 patients met exclusions. Of 101 included patients, only 25 met CCTHR criteria for imaging (24.8%, 95% CI 16.3%-33.2%). Of the 76 patients not meeting criteria, 35 patients underwent additional CT imaging, typically of the cervical spine or face. Six patients had documentation of an outside physician recommending NCHCT, and 8 had documentation of patient request for imaging after being counseled that it was not indicated. Adherence to CCTHR criteria occurred in 6/20 (30.0%, 95% CI 9.9%-50.1%) physician-treated patients and in 19/81 (23.5%, 95% CI 14.2%-32.7%) physician assistant-treated patients, a non-significant difference (p=.54). Over a recent one year period, only 24.8% of patients with mild head trauma undergoing NCHCT aged 16-64 in a low acuity ED team met CCTHR imaging thresholds; no patients had any acute intracranial injury. In this patient population, significant opportunities exist to increase appropriate imaging without decreasing quality of care.