Associated injuries, management, and outcomes of blunt abdominal aortic injury

Abstract

Objective: Blunt abdominal aortic injury (BAAI) is very rare, and current literature is limited to case series of single-center experience. Through an analysis of the National Trauma Data Bank, the largest aggregation of United States trauma registry data, our aim was to characterize the associated injury pattern, contemporary management, and in-hospital outcomes of patients with BAAI.

Methods: We used a nested case-control design. The overall cohort consisted of adult patients (age ≥ 16 years) severely injured (Injury Severity Score ≥ 16) after blunt trauma who were treated at a level 1 or 2 trauma center in years 2007 to 2009. Cases were patients with BAAI and were frequency-matched by age group and mechanism to randomly selected controls at a one-to-five ratio. Multivariable matched analysis (conditional logistic regression) was used to derive adjusted measures of association between BAAI and adjacent arterial, intra-abdominal, and bony injuries.

Results: We identified 436 patients with BAAI from 180 centers. The mean Injury Severity Score was 35 ± 14, and most patients were injured in motor vehicle crashes (84%). Multivariable analysis showed injury to the thoracic aorta, renal and iliac artery, small bowel, colon, liver, pancreas, and kidney, as well as lumbar spine fractures were independently associated with BAAI. A total of 394 patients (90%) were managed nonoperatively, and 42 (10%) underwent repair. Of these 42 patients, 29 (69%) underwent endovascular repair, with 11 patients undergoing open aortic repair and two extra-anatomic bypasses. Median time from admission to repair was 1 day (interquartile range, 1-2 days). Overall mortality was 29%. A total of 271 (69%) patients managed nonoperatively survived to hospital discharge.

Conclusions: The index of suspicion for BAAI should be raised in severely injured patients by the presence of injuries to the lumbar spine, bowel, retroperitoneal organs, and adjacent major arteries. Although endovascular repair is the most common intervention, most patients are managed nonoperatively and survive to hospital discharge.