Respiratory muscle dysfunction is a common consequence of chronic obstructive pulmonary disease (COPD).Weakness or fatigue of the diaphragm and accessory muscles of inspiration is widely recognized in patients on mechanical ventilation. There is increasing evidence to show mechanical ventilation itself may adversely affect the diaphragm's structure and function, which has been termed ventilator-induced diaphragmatic dysfunction. However, in patients with more severe COPD, the benefits of rehabilitation may be limited. In this context, there are new approaches to PR, such as electrical stimulation, a technique that externally stimulates contractions of peripheral muscles to improve peripheral muscle function in patients with severe COPD. This technique consists of placing electrodes on the skin at locations near the motor points of the diaphragm, transmitting an intermittent current, and generating action potentials capable of producing muscle contractions
