Comparison of a Hyperinflation Mode and Air Stacking on Neuromuscular Patients Under Volumetric Ventilation

Inclusion Criteria: * age\>18 years, neuromuscular disease, * restrictive syndrome and/or cough peak flow \< 270.l/mn and/or maximal expiratory pressure \< 40 cm HO2, * patient under non invasive ventilation * steady state for at least one month * written consent form given Exclusion Criteria: * bronchial congestion * hemodynamic instability * previous pneumothorax or emphysema bubbles * Major bulbar dysfunction * plan of legal protection * pregnant or breastfeeding women * no affiliation to a social security scheme