BACKGROUND. Increases in the use of CT to evaluate patients presenting with trauma have raised concern about inappropriate imaging. The evolving utilization of CT for trauma evaluation may be impacted by injury severity. OBJECTIVE. The purpose of this study was to explore patterns in utilization of chest and abdominopelvic CT among trauma-related emergency department (ED) visits across the United States. METHODS. This retrospective study was conducted with national commercial claims information extracted from the MarketScan Commercial Database. Trauma-related ED encounters were identified from the 2011-2018 MarketScan database files and classified by injury severity score (minor, intermediate, and major injuries) on the basis of International Classification of Diseases codes. ED encounters were also assessed for chest CT, abdominopelvic CT, and single-encounter chest and abdominopelvic CT examinations. Utilization per 1000 trauma-related ED encounters was determined. Multivariable Poisson regression models were used to determine incidence rate ratios (IRRs) as a measure of temporal changes in utilization. RESULTS. From 2011 to 2018, 8,369,092 trauma-related ED encounters were identified (5,685,295 for minor, 2,624,944 for intermediate, and 58,853 for major injuries). Utilization of chest CT per 1000 trauma-related ED encounters increased from 4.9 to 13.5 examinations (adjusted IRR, 1.15 per year; minor injuries, from 2.2 to 7.7 [adjusted IRR, 1.17]; intermediate injuries, from 8.5 to 21.5 [adjusted IRR, 1.16]; major injuries, from 117.8 to 200.1 [adjusted IRR, 1.08]). Utilization of abdominopelvic CT per 1000 trauma-related ED encounters increased from 7.5 to 16.4 (adjusted IRR, 1.12; minor injuries, 4.8 to 12.2 [adjusted IRR, 1.13]; intermediate injuries, 10.6 to 21.7 [adjusted IRR, 1.13]; major injuries, 134.8 to 192.6 [adjusted IRR, 1.07]). Utilization of single-encounter chest and abdominopelvic CT per 1000 trauma-related ED encounters increased from 3.4 to 8.9 [adjusted IRR, 1.16; minor injuries, 1.1 to 4.6 [adjusted IRR, 1.18]; intermediate injuries, 6.4 to 16.4 [adjusted IRR, 1.16]; major injuries, 99.6 to 179.9 [adjusted IRR, 1.08]). CONCLUSION. National utilization of chest and abdominopelvic CT for trauma-related ED encounters increased among commercially insured patients from 2011 to 2018, particularly for single-encounter chest and abdominopelvic CT examinations and for minor injuries. CLINICAL IMPACT. Given concerns about increased cost and detection of incidental findings, further investigation is warranted to explore the potential benefit of single-encounter chest and abdominopelvic CT examinations of patients with minor injuries and to develop strategies for optimizing appropriateness of imaging orders.
Keywords: CT; abdominopelvic; chest; emergency department; injury severity score; minor injuries; utilization.