MIE: A pilot physiological study will be performed in patients with neuromuscular disease with acute (10 patients) and chronic (10 patients) secretion management issues that require clinical use of MIE. These patients will be studied using 3 different clearance strategies low pressure MIE, higher pressure MIE and standard airway techniques. The project will assess differences in regional ventilation following augmented airway clearance and inform potential endpoints and feasibility for a larger trial regarding speed of recovery from respiratory infections in patients with neuromuscular disease.