1533. Impact of the COVID-19 Pandemic on Emergency CT Head Utilization in Ontario: An Observational Study of Tertiary Academic Hospitals
Authors * Denotes Presenting Author
  1. Minu Agarwal *; Hamilton Health Sciences; McMaster University
  2. Amar Udare; Hamilton Health Sciences; McMaster University
  3. Abdullah Alabousi; McMaster University; St. Joseph's Healthcare Hamilton
  4. Christian van der Pol; Hamilton Health Sciences; McMaster University
  5. Lucas Ramonas; Health Sciences, University of Ottawa
  6. Milita Ramonas; Hamilton Health Sciences; McMaster University
To determine the impact of the Coronavirus disease-2019 (COVID-19) pandemic on the volume, indications and results of Computed Tomography (CT) heads performed in the Emergency Department (ED) at Canadian tertiary academic centres in Ontario.

Materials and Methods:
A retrospective review of consecutive CT head examinations ordered through the ED during the early stages of COVID-19 pandemic in Canada (March 12 - April 8, 2020) was performed and compared to the pre-COVID-19 period (February 12- March 10, 2020). CT reports were reviewed for the exam indication and the presence of predefined acute findings. Two sample t-test was utilized to compare the cohorts. Daily averages were calculated for all measures to control for the sample size difference between each period. A p-value <0.05 was considered significant.

Of the total 751 CT head reports, 290 (38.6%) were ordered during the pandemic and 461 (61.4%) were ordered pre-pandemic. The average daily volume of CT head orders decreased significantly during COVID-19 compared to pre-COVID-19 (10.4 scans/day vs 16.5 scans/day; p=0.001). In terms of indications, the frequency of ‘non-traumatic intracranial hemorrhage’ was significantly lower during COVID-19 compared to pre-COVID-19(p=0.01). As well, there was a significant increase in acute findings on CT during COVID-19 compared to the pre-COVID-19(p=0.001).

The overall decline in the volume of emergency CT heads performed during the COVID-19 pandemic at our institution was associated with a significant increase in the proportion of cases with acute findings. This suggests a change in the decision-making process of both ordering clinicians as well as patients. While decision support tools are being explored to achieve appropriate imaging, policy makers need to be more cautious about the public messages that are sent out during infectious disease pandemics like COVID-19.