In-exsufflator Cough Assist Device in Patients With Symptomatic Bronchiectasis

Bronchiectasis is characterized by airway dilatation with the potential to cause devastating illness, including repeated respiratory infections requiring antibiotics, disabling productive, mucopurulent cough, shortness of breath and occasional hemoptysis. The damaged and dilated airways lead to persisting bacterial infection of the bronchi and bronchioles, causing inflammation and retained secretions, which in turn may further damage the airways. Patients typically suffer from frequent, severe and refractory episodes of bacterial bronchitis, often requiring hospitalization and prolonged courses of antibiotics. The pathophysiology of bronchiectasis involves the retention of viscid, tenacious inflammatory secretions and microbes leading to a "vicious cycle" of airway obstruction, destruction and recurrent infection with further compromise of the mucociliary clearance host defense apparatus. It has been widely proposed and recommended that methods of enhancing clearance of airway secretions should be an integral component of the care of patients with bronchiectasis. Despite these recommendations and a sound pathophysiologic plausibility given the central role retention of secretions plays in the disease, the effectiveness of interventions targeted toward enhancing bronchopulmonary hygiene has not been systematically studied. It is also not known whether the ability to generate an adequate cough would predict which patient will benefit from these interventions.

The mechanical in-exsufflator device assists patients in clearing retained secretions by augmenting the expiratory flow and force of the patient's cough with the addition of a cycle of positive and negative inspiratory pressure. An effective cough mechanism is actually an important and beneficial host defense which aids in mucus clearance along with the mucociliary apparatus. We hypothesize that daily, regular use of the in-exsufflator device will lead to a reduction in acute bronchiectasis exacerbations- a clinically meaningful endpoint- with other possible beneficial outcomes including improved pulmonary function, improved health-related quality of life and decreased health care costs.

Despite the lack of rigorous, well-designed studies supporting the role and most effective mode of bronchial hygiene physiotherapy in patients with bronchiectasis, many Pulmonologists recommend the flutter valve device as the generally accepted "standard of care" at this time due to its relative non-invasiveness, ease of use and high level of patient acceptability. The flutter valve is a simple, hand-held, pipe-like device which helps loosen secretions by providing an expiratory low-pressure vibratory pulse to the patient's airway when used. This study will provide a comparison of the clinical efficacy of these mechanical chest physiotherapy devices in the setting of bronchiectasis.