Tracheobronchomalacia (TBM) and Excessive Dynamic Airway Collapse (EDAC)

Expiratory central airway collapse has been better understood within the recent years due to development in computed tomography, bronchoscopic imaging and physiologic measurements of flow dynamics in the central airways. This article is a comprehensive narrative review of tracheobronchomalacia (TBM) and excessive dynamic airway collapse (EDAC). We address in detail their pathophysiology and treatment options. The current literature supports the fact that EDAC is essentially distinct from TBM, caused by different factors and may not represent a true central airway disorder that needs invasive treatment such as surgery or stent insertion. Intermittent positive pressure ventilation could function as pneumatic stenting, which helps the selected patients recover from chronic cough and inability to raise secretions. Symptomatic patients with true TBM (crescent type) may need silicone stent insertion, followed by membranous tracheoplasty if symptoms improve. Future research will clarify the flow limitation in EDAC and TBM and assist in determining the appropriate therapy for individual patients.

Keywords: Airway collapse, Choke points, Excessive dynamic airway collapse, Excessive central airway collapse, Flow limiting segments, Tracheobronchomalacia, Tracheomalacia.