Justification Respiratory muscle weakness reduces the efficacy of the cough reflex in patients with neuromuscular disorders and exposes them to the risk of acute respiratory failure. Mechanical insufflation-exsufflation devices assist cough and have been shown to be efficient in increasing the cough expiratory flow in children and adults with neuromuscular disease and decreasing the risk of intubation in a limited population of hospitalized adults with acute respiratory failure.