Chatham M, Bleecker E R, Norman P, Smith P L, Mason P
Chest. 1982 Jul;82(1):15-8. doi: 10.1378/chest.82.1.15.
A screening test to measure nonspecific airways reactivity was developed and compared to a standard methacholine inhalation challenge in 13 asthmatic patients and ten normal control subjects. The screening challenge consisted of one deep breath, then four breaths of a 5 mg/ml methacholine solution followed by one and four breaths of 25 mg/ml of methacholine. Subjects with a history of wheezing received the 5 mg/ml of methacholine first while those without a history of asthma began the challenge at the 25 mg/ml methacholine concentration. Spirometric test were employed and the challenge was terminated when FEV1 fell 20 percent from baseline. The standard methacholine challenge used a dosimeter and all subjects took five breaths of saline solution followed by seven increasing concentrations of methacholine. Dose response curves were constructed and the provocation dose of methacholine that caused a 20 percent fall in FEV1 was calculated for each protocol. Results of the screening methacholine challenge correlated with those obtained from the more lengthy standard protocol (r = 0.94), and correctly identified levels of airways reactivity in asthmatic patients and normal subjects. The abbreviated protocol was rapid (6-12 min), safe, and inexpensive. Since the equipment is readily available and easy to transport, it could be used at sites outside the hospital as a screening test for nonspecific airways reactivity.
我们开发了一种用于测量非特异性气道反应性的筛查试验，并将其与标准的乙酰甲胆碱吸入激发试验进行比较，研究对象包括13名哮喘患者和10名正常对照者。筛查激发试验包括一次深呼吸，然后四次吸入5毫克/毫升的乙酰甲胆碱溶液，接着一次和四次吸入25毫克/毫升的乙酰甲胆碱。有喘息病史的受试者先吸入5毫克/毫升的乙酰甲胆碱，而无哮喘病史的受试者则从25毫克/毫升的乙酰甲胆碱浓度开始激发试验。采用肺量计进行测试，当第一秒用力呼气量（FEV1）从基线下降20%时终止激发试验。标准的乙酰甲胆碱激发试验使用剂量计，所有受试者先吸入五次盐溶液，然后吸入七种浓度递增的乙酰甲胆碱。构建剂量反应曲线，并计算每种方案中导致FEV1下降20%的乙酰甲胆碱激发剂量。筛查性乙酰甲胆碱激发试验的结果与更冗长的标准方案所得结果相关（r = 0.94），并能正确识别哮喘患者和正常受试者的气道反应性水平。简化方案快速（6 - 12分钟）、安全且成本低廉。由于该设备易于获取且便于运输，可在医院外的场所用作非特异性气道反应性的筛查试验。
