Abdominal seat belt marks in the era of focused abdominal sonography for trauma

Hypothesis: Focused abdominal sonography for trauma (FAST) is an unreliable method for assessing intra-abdominal injury in patients with seat belt marks. Design: Retrospective review of trauma patients with intestinal injury and seat belt marks during a 3-year period. Records were reviewed for patient demographics, FAST results, computed tomographic (CT) scan results, and operative findings. The CT scan results were considered positive if bowel wall thickening, extraluminal air, or free fluid without solid organ injury were present. Setting: University hospital designated as a level I trauma center. Patients: Twenty-three patients who required operation for intestinal or mesenteric injury and who had an abdominal seat belt mark. Main Outcome Measure: Sensitivity of FAST in these patients. Results: All patients were evaluated using both FAST and CT scan of the abdomen and pelvis. Eighteen patients (78%) had either negative or equivocal FAST results when significant intestinal injury was present. All 23 patients had CT scan findings suggestive of bowel or mesenteric injury. Moderate-to-large free intraperitoneal fluid without solid organ injury was the most common finding (n = 21, 91%). Operative findings included small-bowel perforation (n = 18, 78%), colonic perforation (n = 7, 30%), bowel deserosalization (n=8, 35%), and isolated mesenteric injury (n=5, 22%). Sixteen patients (70%) had multiple intra-abdominal injuries. All patients were taken directly from the emergency department to the operating room. Seventeen percent of operative explorations (4/23) were non-therapeutic (no repairs required). Conclusion: This study confirms that FAST cannot reliably exclude intestinal injury in patients with seat belt marks.