Impact of the COVID pandemic on emergency department CT utilization: where do we go from here?

Purpose: To analyze the impact of the coronavirus disease (COVID) pandemic on emergency department (ED) computed tomography (CT) utilization.

Methods: A retrospective observational study was conducted assessing seven hospitals' ED imaging volumes between Jan. 6, 2019, and Feb. 27, 2021. Weekly CT utilization is reported as CTs ordered per 100 ED visits. Utilization was ascertained in aggregate and by body area. Interrupted time series analysis was performed to assess significance of utilization change. Prespecified sensitivity analysis was performed for influenza-like or COVID-like illness (ILI/CLI).

Results: Weekly ED CT utilization increased from 35.9 CTs per 100 visits (95% confidence interval [95% CI] 35.8-36.1) to 41.8 per 100 visits (95% CI 41.7-42.0) in pre- and post-pandemic periods. Weekly ED CT chest utilization increased immediately following the pandemic declaration (+ 0.52 chest CTs per 100 ED visits, 95% CI 0.01-1.03, p < 0.05) and compared to pre-pandemic period (+ 0.02 per 100 ED visits, 95% CI 0.02-0.05, p < 0.02). For both CT abdomen/pelvis and CT head, there was neither an immediate effect (+ 0.34 CT-AP per 100 ED visits, 95% CI - 0.74 to 1.44, p = 0.89; - 0.42 CT-H per 100 ED visits, 95% CI - 1.53 to 0.70, p = 0.46) nor a change in weekly CT utilization (+ 0.03 CT-AP per 100 ED visits, 95% CI - 0.01 to 0.05, p = 0.09; + 0.03 CT-H per 100 ED visits, 95% CI - 0.01 to 0.06, p = 0.10).  CONCLUSION: These data may help formulate future strategies for resource utilization and imaging operations as we envision a future with COVID and other federal mandates affecting imaging utilization and appropriateness.