Airway Collapse in Patients With Mounier-Kuhn Syndrome: Titration With Positive Pressure to Reduce Collapse

Airway Collapse in Patients With Mounier-Kuhn Syndrome: Titration With Positive Pressure to Reduce Collapse

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 main signs and symptoms are cough, bulging and purulent expectoration, digital clubbing, dyspnoea, and wheezing.Some of these symptoms are believed to be due to excessive collapse of the intra-thoracic trachea and bronchi, resulting in airways obstruction of more than 50% . The purpose of this study is to identify and reduce tracheal 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.

Tracheal, Bronchial, Tracheobronchiomegaly, Collapse, obstructive sleep apnea syndrome, Computer Tomography, Impedance Tomography

To identify, through bronchoscopy, the prevalence of collapse and whether it is possible to counteract an optimum pressure generated by NIV with CPAP that reduces tracheal and bronchial collapse in patients with SMK; To study the frequency of OSAS in patients with MKS ; Record reversal of collapse with CPAP using chest tomography; To identify the impact of CPAP on the distribution of pulmonary ventilation through the analysis of electrical impedance tomography.

Percentage of tracheal-bronchial collapse area before and after applied positive pressure through bronchoscopy

Identify the prevalence of collapse and whether it is possible to counteract an optimum pressure generated by NIV with CPAP that reduces tracheal and bronchial collapse in patients with SMK

Percentage of tracheal-bronchial collapse area before and after applied positive pressure measure using chest tomography

Inspiratory and expiratory lung volumes before and after applied positive pressure measure using electrical impedance tomography.

To identify the impact of CPAP on the distribution of pulmonary ventilation through the analysis of electrical impedance tomography.

Inclusion Criteria: Has Mounier-Khun Syndrome Accept and signed informed consent form Exclusion Criteria: Other morbidity avoiding study procedures

Divisao de Pneumologia, Instituto do Coracao, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo

Lima E, Nakamura MAM, Genta PR, Rodrigues AJ, Athanazio RA, Rached S, Costa ELV, Stelmach R. Improving Airways Patency and Ventilation Through Optimal Positive Pressure Identified by Noninvasive Mechanical Ventilation Titration in Mounier-Kuhn Syndrome: Protocol for an Interventional, Open-Label, Single-Arm Clinical Trial. JMIR Res Protoc. 2020 Aug 14;9(8):e14786. doi: 10.2196/14786.