<原著>〔第 1 篇〕呼吸困難の呼吸筋筋電図学的研究(肺疾患々者における呼吸困難の研究 : とくに呼吸筋筋電図を中心として)

Abstract

Part I. Electromyographic studies of the respiratory muscles in patients with dyspnea at rest. Electromyograms of respiratory muscles, arterial blood gas analysis, and ventilatory changes were investigated in nine patients with pulmonary diseases and dyspnea at rest. 1) It was found that the sternocleidomastoid muscles participated in the respiratory movements in all cases. Thus the degree of participation of these muscles can be used as an objective index of the severity of dyspnea. Part II. Electromyographic studies on the respiratory muscles in cases of hypoxia, hypercapnia and the artificially increased resistance in the airway. Electromyograms of the respiratory muscles, arterial gas and ventilatory changes were investigated during induced hypoxia, hypercapnia and artificially increased resistance in the airway in patients with pulmonary diseases and no dyspnea at rest but with slightly disturbed pulmonary function. 1) During moderate anoxemia, the sternocleidomastoid muscles were active in only two of six cases, and even when the anoxemia became severe, subjective dyspnea occurred in only one of six cases. 2) During induced hypercapnia, the activity of the sternocleidomastoid muscles increased in six of seven cases, and subjective dyspnea appeared simultaneously. 3) During breathing through artificially increased resistance, the greater the resistance, the more active were the sternocleidomastoid muscles. 4) These results, indicate that the various types of dyspnea can be graded objectively by electromyograqhy of the sternocleidomastoid muscles.