EMG in COPD - Factor Analysis

Acute exacerbations of COPD contribute to significant morbidity and mortality in the United Kingdom (UK). The ability to assess response to treatment during exacerbations that require hospitalisation would allow clinicians to better risk stratify patients for higher or lower level in-patient or out-patient care. Current methods of detecting clinical deterioration are validated in general medical populations and may lack sensitivity and specificity in patients with respiratory morbidity. The use of respiratory muscle EMG to assess neural respiratory drive (NRD) has been demonstrated to be a predictor of readmission in patients admitted to hospital with COPD. The technique has been applied on 'spot' readings of limited duration due to the need for hand analysis of the data. It has been performed by a trained clinical physiologist who removed any interference data and standardised the data gathered. New automated software allows for longer periods of observation, mostly unsupervised, and as a result, the NRD measurements are more likely to be affected by various sources of variability. The influence of clinical and physiological factors as they occur during routine clinical management, such as administration of bronchodilator medication, time of day of readings or proximity to chest physiotherapy, are not yet understood. This trial is designed to gather data to better understand these relationships with NRD.