Utilization of chest CT for injured patients during visits to U.S. emergency departments: 2012-2015.

Introduction: Increased use of computed tomography (CT) during injury-related Emergency Department (ED) visits has been reported, despite increased awareness of CT radiation exposure risks. We investigated national trends in the use of chest CT during injury-related ED visits between 2012 and 2015.

Methods: Analyzing injury-related ED visits from the 2012-2015 United States (U.S.) National Hospital Ambulatory Medical Care Survey (NHAMCS), we determined the percentage of visits that had a chest CT and the diagnostic yield of these chest CTs for clinically-significant findings. We used survey-weighted multivariable logistic regression to determine which patient and visit characteristics were associated with chest CT use.

Results: Injury-related visits accounted for 30% of the 135 million yearly ED visits represented in NHAMCS. Of these visits, 817,480 (2%) received a chest CT over the study period. The diagnostic yield was 3.88%. Chest CT utilization did not change significantly from a rate of 1.73% in 2012 to a rate of 2.31% in 2015 (p = 0.14). Multivariate logistic regression demonstrated increased odds of chest CT for patients seen by residents versus by attendings (adjusted odds ratio [AOR] 2.08, 95% confidence interval [CI] 1.41-3.08). Patients aged 18-59 and 60+ had higher AORs (5.75, CI 3.44-9.61 and 9.81, CI 5.90-16.33, respectively) than those <18 years of receiving chest CT.

Conclusions: Overall chest CT utilization showed an increased trend from 2012 to 2015, but the results were not statistically significant.