Single emergency department charts 90% uptick in CT use since 2015

A single emergency department is charting a 90% uptick in CT use since 2015, coinciding with a greater decrease in admissions among patients who underwent such imaging. 

Computed tomography is the most widely used and fastest growing advanced imaging modality, primarily driven by EDs. “Growing concern” has suggested that this may be due at least in part by wasteful overuse of healthcare resources for services that deliver little benefit to patients.

Experts with Curtin University in Perth, Australia, sought to better understand these trends, analyzing data from their institution spanning 2015 to 2022. They noted that the number of ED episodes increased by only 8% while the number of scans was up 90% during the same period, according to research published in Insights into Imaging. 

“Our findings align with recent trends from the United States, where CT scan rates in two EDs increased substantially between 2014 and 2021,” lead author Fouziah Almouqati, with the Curtin School of Population Health, and colleagues advised. 

The CT scans per 1,000 ED episodes during this period increased by about 76% (or from 111 to 195) or 47% (118 to 173) when adjusting for various mitigating factors. Hospital admission rates were consistently higher for patients who underwent CT but declined over time for both groups. Compared to those without CT, the admission rate among those who did decreased by about 2.17% during the study period. Experts noted there was a “clear upward shift” in imaging rates beginning in 2020, potentially driven by the COVID-19 pandemic. 

The rate of CT was up significantly even after adjusting for variations in age, triage, socioeconomic disadvantage and other characteristics. This likely indicates that the increase is not simply attributable to these factors, but likely reflects “changes in clinical practice, with a greater propensity for CT use.” 

“Physician decision-making is likely influenced by interrelated factors. Efforts to manage patient flow and reduce overcrowding have been linked to increased CT use in ED,” the authors advised. 

The practice of defensive medicine may have partly played a part in increasing CT use, the authors speculated. Common drivers of this may include criticism from colleagues and perceived malpractice risk. During the study period, complaints regarding healthcare services, including EDs, rose from 1,777 at the beginning of the study period up to 2,299. Technological advancements, such as iterative image reconstruction, have led to reductions in CT radiation does across all scan types in Australia. This, too, may have made referrers feel more comfortable in ordering exams with less worry about radiation exposure, the authors speculated. 

“While current ordering practices may indicate cost savings from avoided hospitalizations, they could also suggest increased scanning of lower-risk patients and potential overuse,” Almouqati et al. concluded. “This study began with the implementation of Choosing Wisely in Australia in 2015, highlighting the need for a formal investigation into the campaign’s impact.”