Pathophysiology
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.