Evaluation of the Presence of Airway Collapse in Patients With Mounier-Kuhn Syndrome and Titration With Continuous Positive Pressure Through Non-invasive Mechanical Ventilation to Reduce Collapse

Mounier-Kuhn syndrome (MKS), or congenital tracheobronchiomegaly, is an entity characterized by dilation of the trachea and bronchi, associated with respiratory infections. The prevalence among patients with respiratory symptoms is 0.4 to 1.6%. Its histological features include the atrophy or absence of longitudinal elastic fibers and smooth muscle cells of the airways, responsible for the structural alterations found, such as tracheobronchiomegaly, the presence of inter cartilaginous diverticula, bulging and dilation of the walls of the trachea and bronchi. The main signs and symptoms are cough, bulging and purulent expectoration, digital clubbing, dyspnoea, and wheezing and wheezing accompanied by recurrent respiratory infection. There may be association with other comorbidities such as gastroesophageal reflux disease, chronic obstructive pulmonary disease, bronchiectasis and obstructive sleep apnea / hypopnea syndrome (OSAS). Some of these symptoms are believed to be due to the tracheobronchial disease present in some patients, defined by excessive collapse of the intrathoracic trachea and bronchi resulting in airways obstruction of more than 50%. The main clinical impact is obstruction to expiratory airflow, with consequent air entrapment, reduction of cough and bronchial hygiene effectiveness, facilitating recurrent respiratory infections. Because it is a rare morbidity and little studied, the specific therapy is not consensual, and the main interventions are extrapolated from other pathologies. The use of non invasive mechanical ventilation (NIMV) with continuous positive airway pressure (CPAP) is reported as an option for treatment, however, there are no randomized studies proving its efficacy. The purpose of this study is to identify and reduce tracheal collapse and bronchi of SMK carriers with the use of positive pressure (CPAP-NIV) and to analyse their repercussion in the small airways.