From the Guidelines
The main cause of Excessive Dynamic Airway Collapse (EDAC) and bronchomalacia is structural weakness of the airway walls, which can be congenital or acquired due to various factors such as chronic inflammation, prolonged intubation, or external compression. In EDAC, there is excessive inward bulging of the posterior membrane of the trachea and main bronchi during expiration, while bronchomalacia involves weakness of the cartilaginous rings that normally maintain airway patency. According to the most recent study 1, nonmalignant central airway obstruction, including tracheobronchomalacia and excessive dynamic airway collapse, can be managed with therapeutic bronchoscopy or open surgical resection. The structural weakness leads to excessive airway narrowing during expiration when intrathoracic pressure increases, causing symptoms like dyspnea, wheezing, cough, and recurrent respiratory infections. Key factors contributing to this condition include:
- Chronic inflammation from conditions like COPD
- Prolonged intubation
- Recurrent infections
- Chronic cough
- Prolonged external compression from structures like vascular anomalies, tumors, or enlarged lymph nodes. Treatment typically focuses on managing underlying conditions, respiratory therapy techniques, and in severe cases, stenting or surgical interventions may be considered, as suggested by 1 and 1. Understanding the pathophysiology helps guide appropriate management strategies for these challenging airway disorders.
From the Research
Main Cause of Excessive Dynamic Airway Collapse (EDAC) and Bronchomalacia
The main cause of Excessive Dynamic Airway Collapse (EDAC) and bronchomalacia is not explicitly stated in the provided studies. However, the following points can be inferred:
- EDAC is characterized by excessive narrowing of the airway lumen during exhalation, leading to dyspnea, cough, mucostasis, recurrent respiratory infections, and poor quality of life 2.
- Tracheobronchomalacia and EDAC are heterogeneous entities with different pathophysiology, but similar symptoms and diagnostic and therapeutic work-ups 2.
- The condition can be caused by a weakness of the tracheobronchial cartilaginous structures (tracheobronchomalacia) or excessive bulging of the posterior membrane into the airway lumen during exhalation (EDAC) 3.
- Airway malacia, including laryngomalacia, tracheomalacia, and bronchomalacia, can occur due to increased airway compliance, resulting in excessive dynamic collapse during the respiratory cycle 4.
- EDAC can also be present in obstructive lung diseases, such as chronic obstructive pulmonary disease (COPD), due to dynamic compressive forces during expiration 5.
Key Factors Associated with EDAC and Bronchomalacia
Some key factors associated with EDAC and bronchomalacia include:
- Chronic airway inflammation 5
- Dynamic compressive forces during expiration 5
- Increased airway compliance 4
- Weakness of the tracheobronchial cartilaginous structures 3
- Excessive bulging of the posterior membrane into the airway lumen during exhalation 3
Diagnosis and Treatment
Diagnosis of EDAC and bronchomalacia is typically based on dynamic flexible bronchoscopy and/or dynamic computed tomography scan, as well as clinical symptoms 2, 3. Treatment options include: