García Río F, Prados C, Díez Tejedor E, Díaz Lobato S, Alvarez-Sala R, Villamor J, Pino J M
Respiratory Services, La Paz Hospital, School of Medicine, Autonoma University, Madrid, Spain.
Thorax. 1994 Jul;49(7):703-6. doi: 10.1136/thx.49.7.703.
Myasthenia gravis is a specific autoimmune disease characterised by weakness and fatigue. Respiratory muscle weakness has been studied using the determination of maximal respiratory pressures, but the response of respiratory centres is not well characterised. This study was undertaken to determine the breathing pattern and the central ventilatory drive in patients with mild and moderate generalised myasthenia gravis.
Twenty four patients with myasthenia gravis were studied, divided into two groups. Group 1 included 13 subjects (eight women and five men aged 23-64) with mild generalised myasthenia gravis, and group 2 was composed of 15 patients (11 women and four men aged 23-69) with moderate generalised myasthenia gravis. A control group comprised 15 healthy persons with a similar age and sex distribution. Spirometric measurements and maximal respiratory pressures were performed under basal conditions in all subjects, and the rate and depth of breathing and the inspiratory occlusion pressure in the mouth in the first 0.1 second (P0.1) were measured.
No difference was detected for parameters of breathing pattern between patients in group 1 and control subjects, although P0.1 was higher in those in group 1. Subjects in group 2 had a lower tidal ventilation, shorter inspiratory time, and a higher frequency with a higher P0.1 than control subjects.
Mild myasthenia gravis causes increased neuromuscular drive with a normal breathing pattern. Moderate myasthenia gravis is characterised by a more rapid shallow breathing pattern.
重症肌无力是一种以肌无力和疲劳为特征的特异性自身免疫性疾病。虽然已通过测定最大呼吸压力对呼吸肌无力进行了研究，但呼吸中枢的反应尚未得到充分描述。本研究旨在确定轻度和中度全身型重症肌无力患者的呼吸模式和中枢通气驱动。
对24例重症肌无力患者进行了研究，分为两组。第1组包括13名受试者（8名女性和5名男性，年龄23 - 64岁），患有轻度全身型重症肌无力；第2组由15例患者（11名女性和4名男性，年龄23 - 69岁）组成，患有中度全身型重症肌无力。对照组由15名年龄和性别分布相似的健康人组成。在所有受试者的基础条件下进行肺量计测量和最大呼吸压力测定，并测量呼吸频率和深度以及口腔内吸气阻断压力在最初0.1秒时的值（P0.1）。
第1组患者与对照组受试者之间的呼吸模式参数未检测到差异，尽管第1组患者的P0.1较高。第2组受试者的潮气量较低，吸气时间较短，频率较高，且P0.1高于对照组受试者。
轻度重症肌无力导致神经肌肉驱动增加，呼吸模式正常。中度重症肌无力的特征是呼吸模式更快且更浅。
