Introduction

Tracheobronchomalacia) rather expiratory airway collapse (ECAC) corresponds to the collapse of more than 50% of the diameter of the trachea and/or main bronchi during exhalation. The term expiratory tracheobronchial collapse includes two entities: TBM, a disease of the cartilage rings, and Excessive Dynamic Airway Collapse (EDAC), a major bulge of the membranosa at the level of the posterior wall. The prevalence of TBM in adults is discussed. The symptoms and signs are based on nonspecific respiratory signs such as dyspnea. 

The diagnosis is obtained during dynamic tests, by bronchial endoscopy and/or CT scan.TBM can be primary (genetic, idiopathic) or secondary, related to trauma, tracheostomy, intubation, surgery, transplantation, emphysema, infection, inflammation, chronic bronchitis, extrinsic compression, or vascular rings undiagnosed in childhood. Some therapeutic decision-making algorithms have been proposed,  but no specific recommendations have been established. Treatment is reserved for symptomatic patients. First, it is medical treatment with bronchodilators, corticosteroids, and antibiotics. If this fails, non-invasive ventilation(NIV) may be discussed. If symptoms persist, the placement of tracheobronchial prostheses by interventional bronchoscopy can prevent collapse of the airways, for palliative or curative purposes (postoperatively after a major lung resection, for example). This indication must weigh the benefits and risks, particularly in the long term, of tracheobronchial stents. In previously selected patients, the placement of stents may be the first step before surgery: tracheal resection, external reinforcement of the anterior wall, or tracheobronchoplasty (TBP) (stabilization of the posterior wall by a polypropylene or biological prosthesis). These different options are still being discussed.¹

Pathophysiology of Tracheobronchomalacia (TBM)

Tracheobronchomalacia is  characterisedby a weakening of the structural integrity of the trachea and bronchi due to abnormalities in the cartilage, smooth muscle, or connective tissue. Normally, the tracheal cartilage rings provide support to maintain airway patency during breathing. In TBM, these cartilaginous structures become soft, leading to excessive collapsibility of the airway, particularly during exhalation or coughing.²

The collapse may be caused by factors such as chronic inflammation, mechanical trauma, or congenital defects. This results in impaired airflow, ineffective clearing of secretions, and increased susceptibility to respiratory infections. Over time, the condition can significantly compromise respiratory function, reducing the patient's quality of life and necessitating targeted management strategies.³

Clinical Presentation

• Symptoms:
  • Shortness of breath (dyspnea)
  • Chronic cough and wheezing
  • Recurrent respiratory infections, due to ineffective airway clearance
  • Stridor or a sensation of airway obstruction, especially during exertion or coughing
• Diagnostic Tools:
  • Bronchoscopy: Direct visualisation visualization of dynamic airway collapse during breathing
  • Computed Tomography (CT) Scan: Detailed imaging to assess airway anatomy and extent of collapse
  • Pulmonary Function Tests (PFTs): Evaluate airflow obstruction and lung function

Non-Surgical Management Strategies for Tracheobronchomalacia 

Pharmacological Approaches

• Bronchodilators: Beta-agonists and anticholinergics to improve airway function⁴
• Anti-inflammatory Medications: Inhaled and systemic corticosteroids to reduce inflammation⁵
• Antibiotics: For managing recurrent infections
• Mucolytics: Aid in clearing mucus and improving airflow⁶

Airway Clearance Techniques

• Chest physiotherapy and positive expiratory pressure (PEP) therapy
• High-frequency chest wall oscillation to remove secretions⁷

Non-Invasive Ventilation (NIV)

• CPAP: Prevents airway collapse by providing constant pressure
• BiPAP: Offers pressure support for breathing during inhalation and exhalation

Lifestyle and Supportive Measures

• Smoking cessation and avoidance of respiratory irritants
• Adequate hydration and participation in pulmonary rehabilitation programs

Speech Therapy

• Breathing exercises and cough mechanics training to strengthen respiratory muscles.

Psychological Support

• Stress management and coping strategies to address the impact of chronic illness on mental health.

Emerging Therapies and Innovations

• Novel Pharmacological Agents: Development of drugs targeting airway remodeling and inflammation, such as biologics and small-molecule inhibitors
• Advanced Ventilation Devices: New-generation CPAP and BiPAP machines with better adaptability and patient comfort⁸
• Regenerative Medicine: Experimental use of stem cell therapy to repair damaged airway tissues
• AI-Driven Personalized Management: Utilisation of artificial intelligence for individualized treatment plans, prediction of disease progression, and  optimisation of therapeutic outcomes⁹
• 3D-Printed Airway Stents: Custom-designed stents to provide support to collapsing airways⁸
• Wearable Monitoring Technology: Devices to continuously track respiratory parameters and detect early signs of exacerbation

 Challenges in Non-Surgical Management

• Limited Efficacy of Therapies: Current non-surgical strategies may not provide complete symptom relief or halt disease progression¹⁰
• Patient Compliance: Difficulty adhering to complex airway clearance regimens or long-term use of devices like CPAP or BiPAP
• Recurrent Infections: Persistent airway collapsibility increases susceptibility to infections, complicating management¹¹
• Individual Variability: Variations in response to treatments necessitate personalised approaches, which can be resource-intensive
• Access to Advanced Therapies: Emerging technologies, such as AI-driven management or regenerative medicine, may not be widely available
• Psychosocial Impacts: Chronic symptoms and the need for lifelong management can lead to psychological distress and reduced quality of life¹²

Prognosis and Long-Term Management

The prognosis for individuals with tracheobronchomalacia varies widely. Infants with congenital TBM often experience improvement as they grow and the airway structures strengthen. In adults, the outlook depends on the underlying cause and the success of treatment interventions.

Long-term management requires a multidisciplinary approach, involving pulmonologists, otolaryngologists, and respiratory therapists. Regular follow-up and monitoring are essential to address any complications and adjust treatment plans as needed.¹³

Conclusion

In conclusion, non-surgical management of tracheobronchomalacia (TBM) primarily aims to alleviate symptoms and improve respiratory function without the need for invasive procedures. Key strategies include airway through the use of positive pressure devices such as continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BiPAP), which help maintain airway patency, especially during sleep. 

Pharmacologic interventions, including bronchodilators and corticosteroids, are employed to reduce airway inflammation and smooth muscle constriction. Chest physiotherapy and techniques like positive expiratory pressure (PEP) devices can assist in mucus clearance and improve overall airway dynamics. In some cases, endoscopic approaches like stent placement or balloon dilation may provide temporary relief for patients with significant symptoms. Close monitoring and individualized treatment plans are essential to  optimise outcomes and prevent disease progression.