Clinical meaning
Tracheobronchial injury (TBI) involves disruption of the tracheobronchial tree from blunt or penetrating trauma, iatrogenic injury, or rarely, spontaneous rupture. Blunt TBI typically occurs within 2.5 cm of the carina (80% of injuries), where the bronchi are fixed and less mobile. The mechanism involves sudden anteroposterior thoracic compression increasing intraluminal pressure against a closed glottis, causing mucosal or transmural tears. Penetrating injuries can affect any level. Iatrogenic TBI from intubation typically involves the posterior membranous tracheal wall (most vulnerable). Clinical presentation ranges from subcutaneous emphysema and pneumomediastinum to massive air leak with respiratory failure. The classic sign is persistent pneumothorax that does not resolve with chest tube placement (continuous large air leak). Delayed diagnosis is common (50% diagnosed > 24 hours) because smaller tears may initially be contained by surrounding tissue.
Diagnosis & workup
Diagnostics & workup: - Clinical signs: subcutaneous emphysema (neck, chest, face), pneumomediastinum, persistent pneumothorax with large air leak despite chest tube - CXR: pneumomediastinum, subcutaneous emphysema, persistent pneumothorax, 'fallen lung sign' (collapsed lung falls peripherally rather than toward hilum — pathognomonic for complete bronchial disruption) - CT chest: pneumomediastinum, airway wall discontinuity, peribronchial air, tracheal deformity - Bronchoscopy: GOLD STANDARD for diagnosis — directly visualizes tear location, extent, and depth (mucosal vs transmural) - Chest tube output assessment: persistent large air leak (> 5-7 days) or failure of lung to re-expand suggests TBI - Clinical triad in blunt TBI: subcutaneous emphysema + pneumomediastinum + pneumothorax - Serial CXR: worsening subcutaneous emphysema or persistent air leak despite chest drainage - CT 3D airway reconstruction: preoperative planning for surgical repair