Incidence and significance of injuries on secondary CT imaging after initial selective imaging in blunt trauma patients

Objective: It is unclear if additional computerized tomography (CT) imaging is warranted after injuries are identified on CT in blunt trauma patients. The objective of this study was to determine the incidence and significance of injuries identified on secondary CT imaging after identification of injuries on initial CTs in blunt trauma patients. Methods: This was a retrospective cohort study at an academic Level 1 trauma center with a two-tiered trauma system. Inclusion criteria: age ≥ 18, level 2 trauma activation, injury identified on initial CT, and secondary CTs ordered. Secondary injuries were categorized as resulting in: no changes, minor changes, or major changes in management. Results: 537 patients underwent 1179 initial CT scans which identified 744 injuries. There were 1094 secondary CTs which identified 143 additional injuries in 94 (18%) patients. 9 (1.7%) patients had at least one major management change and 64 (12%) had at least one minor management change. Rib fracture(s) was the most common injury on secondary scans [45/143 (32%)]. The major management changes were: tube thoracostomy for pneumothorax (4 patients), blood transfusion for hemoperitoneum (1 patient), surgery for acetabular fracture (1 patient), thoracolumbar brace for spine fracture (2 patients) and angiography for splenic injury (1 patient). Conclusion: While a significant proportion of patients (18%) had injuries on secondary CT, only 1.7% of patients had a resultant major management change. Future research is warranted to determine the need for additional CT imaging after an initial selective imaging strategy in blunt trauma patients.