Using CT to diagnose tracheal rupture

OBJECTIVE. A retrospective study was performed to assess CT sensitivity for diagnosing tracheal rupture. Intubated cadaver tracheas were examined to a ssess endotracheal tube balloon overdistention and deformity and to evaluat e the relationship of balloon pressures to tracheal injury. MATERIALS AND METHODS. Week or chest CT scans of 14 patients with tracheal rupture and 41 control trauma patients with pneumomediastinum but without t racheal injury were reviewed and compared to assess the presence and locati on of extrapulmonary air, whether direct visualization of tracheal wall dis ruption was possible, the size and shape of endotracheal tube balloon, sign s of transtracheal balloon herniation in intubated patients, and the locati on of the extratracheal endotracheal tube. Intact and experimentally injure d cadaver tracheas were used to evaluate tube balloon pressure and configur ation. RESULTS. All 14 patients with tracheal rupture had deep cervical air and pn eumomediastinum. Overdistention of the tube balloon occurred in 71% (5/7) o f the intubated patients, and balloon herniation occurred in 29% (2/7), Dir ect tracheal injury was seen in 71% (10/14) of the patients as a wall, defe ct (n = 8) or deformity (n = 2). Overall, CT was 85% sensitive for detectin g tracheal injury: Patients with tracheal injury had a significantly lower incidence of pneumothorax (p = 0.01) than did the control group. The CT app earance of balloon herniation through defects in the cadaver tracheas close ly mimicked those of patients with tracheal injury, The amount of balloon p ressure required to rupture the intubated trachea was extremely high and ru pture was difficult to obtain. CONCLUSION. CT can reveal tracheal injury and can be used to select trauma patients with pneumomediastinum for bronchoscopy, leading to early confirma tion and treatment.