本文旨在探讨中至重度慢性阻塞性肺疾病(COPD)患者严重呼吸困难与膈肌疲劳的关系,以及茶碱对膈肌疲劳的作用。方法 8例中至重度 COPD 采用随机双盲交叉法,给予缓释型茶碱或安慰剂,每人试验2次,其间间隔3天。首先,4例接受茶碱,另4例接受安慰剂,试验前3天每12h 给药1次。每天早晨对患者进行肺量测定,随之每隔5min 吸入舒喘宁1次共4次,10min 后再重复肺量测定。接着进行踏车试验,脚踩50 This article aims to investigate the relationship between severe dyspnea and diaphragmatic fatigue in patients with moderate to severe chronic obstructive pulmonary disease (COPD) and the effect of theophylline on diaphragmatic fatigue. Methods Eight patients with moderate-to-severe COPD were randomized double-blind crossover study. They were given sustained-release theophylline or placebo twice a day for 3 days. First, 4 received theophylline, and the other 4 received placebo. The drug was given every 12 hours 3 days before the test. Spirometry was performed on patients every morning, followed by inhalation of albuterol once every 5 minutes for a total of 4 times, and then repeated spirometry 10 minutes later. Then treadmill test, foot 50