Can Waveform and Flow Traces From Mechanical Insuflattion:Exsufflation (MI:E) be Used to Identify Laryngeal Responses to MI:E and Thus Optimise Treatment Algorithms?

Objectives: * To establish if physiotherapists can use the waveform traces from the cough assist machine to work out when patients are having an abnormal airway response to cough assist * To establish how cough assist device settings, particularly in breath and cough pressures affect a patient's response to using the cough assist device * To provide some clinical guidance to physiotherapists on methods for assessing and treating abnormal airway responses to cough assist devices Methodology: Subjects will complete breathing tests; spirometry, peak cough flow (PCF) and sniff nasal inspiratory pressure (SNIP) to establish baseline breathing function and rule out anyone with breathing conditions. A nasal camera will be used to look at the voice box at rest. Cough assist will be delivered via a face mask which will allow for simultaneous use of the nasal camera and cough assist carried out in the same way as another research team have done previously. The nasal camera will be attached to a video camera to allow recording, analysis and documentation of the observations. The cough assist protocol will be delivered by a physiotherapist experienced in delivering cough assist. Cough assist waveforms will be downloaded into Care Orchestrator software (Philips Respironics, Murraysville, USA) and reviewed at the same time as the nose camera recordings to establish if voice box responses can be identified from the waveform patterns. For confirmation of Care Orchestrator software waveforms, a device that records airflow during breathing (spirometer) will be connected (Alpha touch, Vitalograph, Ennis, Ireland) into the cough assist circuit in the same way another research team has before.