Blunt chest trauma and suspected aortic rupture: Reliability of chest radiograph findings

The chest radiographs of 86 patients with suspected aortic rupture from blunt chest trauma were reviewed. Seventy-three patients had no evidence of aortic rupture on aortography or surgical exploration, and 13 patients had surgically confirmed rupture. Sixteen radiographic findings were analyzed for sensitivity and specificity in detecting aortic rupture. The following findings were not statistically significant: hemothorax on either side; rib fractures on either side; pneumothorax on either side; lung contusion; widened left paravertebral stripe; and widening of the mediastinum, along with an increased ratio of mediastinal width to chest width. The most helpful findings leading to suspicion of aortic rupture included nasogastric tube or tracheal deviation to the right at the T4 level; depression of the left mainstem bronchus; and loss of the aortic contour or knob and left apical cap. False positives and false negatives occurred with each radiographic sign, indicating that there is no single finding that is absolutely reliable in predicting or excluding significant injury in every patient with suspected aortic rupture. Analysis of combinations of findings found that when the aortic contour and knob are normal and the nasogastric tube and trachea are not deviated, there was no case of aortic rupture in four consecutive years of experience. These four signs can be used to exclude aortic rupture.