A Clinical Decision Instrument to Safely Reduce Abdominopelvic CT Use in Minor Blunt Trauma Patients

Background Abdominopelvic (A/P) computed tomography (CT) is frequently used in trauma evaluation, yet often yields clinically insignificant findings, especially in minor blunt trauma. Overuse of CT is associated with radiation exposure, contrast risks, and unnecessary healthcare costs. Objective To derive a clinical decision instrument (DI) to guide selective A/P CT imaging in adult patients presenting with minor blunt trauma. Methods We conducted a retrospective cohort study of adults presenting to the emergency department with minor blunt trauma and underwent A/P CT in the emergency department (ED) of Tel-Aviv Sourasky Medical Center between 2018 to 2022. Clinically meaningful A/P injuries were defined as those necessitating therapeutic intervention or hospital admission for observation. Multivariable logistic regression identified independent predictors of injury. Diagnostic performance was assessed using ROC analysis, calculating its sensitivity, specificity and negative predictive value (NPV). Results Among 894 patients (median age 43.8 years, 62.2% male), 89 (9.9%) experienced clinically meaningful outcomes. The DI incorporated five independent predictors for clinically meaningful injury: Distracting injury (aOR 5.5 [95% CI 2.9–10.4], p < 0.001), Abdominal / pelvic pain and/or tenderness (aOR 2.8 [95% CI: 1.5-5.0], p < 0.001), Abdominal / pelvic bruises/hematoma (aOR 2.2 [95% CI 1.2–4.1], p = 0.008), and chronic disease (aOR 2.8 [95% CI: 1.4–5.7], p = 0.003), and abnormal pelvic radiograph (predefined as mandatory). Application of the DI would have recommended imaging in 479 patients (53.3%). The DI achieved sensitivity of 96.6% (95% CI: 90.5–98.8%), specificity of 51.2% (95% CI: 47.5–54.8%), and negative predictive value (NPV) of 99.3% (95% CI: 97.9–99.8%). ROC analysis demonstrated an AUC of 0.74 (p = 0.02). Of 89 patients with clinically meaningful injuries, 3 (0.3%) did not meet any DI criteria; all were managed conservatively. Conclusions Our proposed DI demonstrated high sensitivity and NPV while potentially reducing A/P CT utilization by nearly half. Implementation of such a tool may safely decrease unnecessary imaging in minor blunt trauma, minimize radiation and contrast exposure, and improve resource use. Prospective validation is recommended.