Moy M L, Woodrow Weiss J, Sparrow D, Israel E, Schwartzstein R M
Divisions of Pulmonary and Critical Care Medicine, Departments of Medicine, Beth Israel Deaconess Medical Center and Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.
Am J Respir Crit Care Med. 2000 Aug;162(2 Pt 1):451-5. doi: 10.1164/ajrccm.162.2.9907138.
To test the hypothesis that patients perceive the same quality of dyspnea during mild bronchoconstriction and external resistive loads, we studied subjects with asthma under two conditions: (1) during methacholine bronchoprovocation to mimic the bronchospasm of mild asthma and (2) while breathing on a circuit to which was added a range of external resistors to mimic the mechanical load of mild asthma. During each of these stimuli, respiratory variables, overall dyspnea intensity on a modified Borg scale, and the qualitative descriptors of breathlessness from a 19-item questionnaire were assessed. The "chest tightness" and "constriction" responses were significantly more frequent in the methacholine trials as compared with the external load trials (p < 0.0001). The "chest tightness" or "constriction" response was chosen during 92% of the 26 trials of methacholine bronchoconstriction compared with 3% of the 72 trials of breathing against the external resistors. Changes in functional residual capacity were not significantly different between the two conditions. We conclude that in mild asthma, the sensation of chest tightness is distinct from the sensation of work and effort and is not attributable to the mechanical load imposed on the respiratory system.
为验证患者在轻度支气管收缩和外部阻力负荷期间感知到相同程度呼吸困难的假设，我们对哮喘患者在两种情况下进行了研究：（1）在乙酰甲胆碱支气管激发试验期间，以模拟轻度哮喘的支气管痉挛；（2）在连接一系列外部电阻器的回路中呼吸，以模拟轻度哮喘的机械负荷。在每种刺激期间，评估呼吸变量、改良Borg量表上的总体呼吸困难强度以及一份包含19个条目的问卷中关于呼吸急促的定性描述词。与外部负荷试验相比，乙酰甲胆碱试验中“胸部发紧”和“收缩感”反应明显更频繁（p < 0.0001）。在26次乙酰甲胆碱支气管收缩试验中，92%的试验选择了“胸部发紧”或“收缩感”反应，而在72次对抗外部电阻器呼吸试验中，这一比例为3%。两种情况下功能残气量的变化无显著差异。我们得出结论，在轻度哮喘中，胸部发紧的感觉与工作和用力的感觉不同，且并非归因于施加在呼吸系统上的机械负荷。
