Analysis of vibromyographic and electromyographic signals from sternomastoid muscle in COPD patients

Analysis of the respiratory muscles activity is a promising technique for diagnosis of respiratory diseases, such as chronic obstructive pulmonary disease (COPD). The sternomastoid muscle was selected to study the activity of respiratory muscles, due to its accessibility. This work proposes the analysis of vibromyographic and electromyographic signals from the sternomastoid muscle, in order to evaluate the muscle function in a ventilatory test. Spectral analysis was performed. The Welch periodogram and autoregressive models were used. Results from a group of 5 patients with COPD are shown at different levels of inspiratory loads. Activity of sternomastoid muscle was measured by means of root-mean-square (rms) values and mean and median frequencies, and they were related to level of severity of COPD patients.