Dynamic airway collapse: Distinct from tracheomalacia

Large airway collapse can occur in various diseases. Certain conditions such as tracheomalacia (TM) portend a poor prognosis. We sought to identify a more benign entity in which airway collapse is dynamic and contrasts to the poor prognosis of TM. We performed a retrospective analysis of bronchoscopically diagnosed dynamic airway collapse. Individuals undergoing bronchoscopy with a coexisting diagnosis of chronic obstructive pulmonary disease or asthma on the bronchoscopy report were included. Their report was reviewed for evidence of large airway collapse noted during the procedure. We identified 31 patients (18 males) with a mean age of 60 years. A more common reason for bronchoscopy was either airway obstruction or respiratory insufficiency. The only nearly consistent finding on pulmonary function testing was a reduction in maximum voluntary ventilation. Twenty-two patients had follow-up information over a mean of 5.5 years. Among this group, 12 patients experienced improvement without any intervention and an additional 4 improved with nocturnal positive airway pressure devices. Only 1 patient required permanent tracheostomy. Five patients had a previous diagnosis of TM that proved to be incorrect. Two of these patients were improperly treated with metallic airway stents. In conclusion, dynamic airway collapse (DAC) is a more benign process than TM with 73% of individuals improving with minimal intervention. Thus, careful evaluation is needed to differentiate DAC from TM. We would caution against the use of airway prosthesis in the majority of patients with DAC.