Primary objective The goal is to record the efficacy of mechanical insufflation-exsufflation (MI-E) during acute respiratory failure in patients with neuromuscular disorders.The primary objective is the reduction of the number of patients requiring invasive ventilatory support (endotracheal intubation or tracheotomy) in the group treated with MI-E (MI-E group) compared to the group treated with traditional chest physiotherapy without MI-E (Control group).