Mahler Donald A
Dartmouth Medical School, Lebanon, NH 03756-0001, USA.
Proc Am Thorac Soc. 2006 May;3(3):234-8. doi: 10.1513/pats.200509-103SF.
Patients with chronic obstructive pulmonary disease (COPD) describe their breathlessness as related to the work and effort associated with breathing. Current evidence suggests that the perception of dyspnea is due to a "mismatch" between the outgoing motor command from the central nervous system and the corresponding afferent information from chemoreceptors and/or mechanoreceptors. To measure the severity of dyspnea the principles of psychophysics (stimulus --> response relationship) can be applied. One approach is to consider activities of daily living as a putative stimulus. Although this method relies on patient recall and description of daily tasks, ability to function, as well as time and effort to complete an activity, select clinical instruments have demonstrated appropriate measurement criteria in randomized clinical trials involving patients with COPD. Another approach is for a patient to report the intensity of dyspnea during exercise, and current practice is to provide ratings each minute "on cue" during the exercise test. A computerized system has been developed whereby the person can report ratings spontaneously and continuously by moving a computer mouse that adjusts a vertical bar adjacent to 0-10 category-ratio scale positioned on a monitor. With this continuous method the patient reports twice the number of dyspnea ratings during exercise compared with discrete ratings each minute. Patient-reported dyspnea based on activities of daily living and exercise testing provides distinct but complimentary information.
慢性阻塞性肺疾病（COPD）患者称其呼吸困难与呼吸相关的工作和努力有关。目前的证据表明，呼吸困难的感知是由于中枢神经系统发出的传出运动指令与来自化学感受器和/或机械感受器的相应传入信息之间存在“不匹配”。为了测量呼吸困难的严重程度，可以应用心理物理学原理（刺激→反应关系）。一种方法是将日常生活活动视为一种假定的刺激。尽管这种方法依赖于患者对日常任务的回忆和描述、功能能力以及完成一项活动所需的时间和精力，但在涉及COPD患者的随机临床试验中，某些临床工具已显示出适当的测量标准。另一种方法是让患者报告运动期间呼吸困难的强度，目前的做法是在运动测试期间每分钟“按提示”提供评分。已经开发出一种计算机化系统，通过移动计算机鼠标来调整与显示器上0至10类别比例量表相邻的垂直条，患者可以自发且连续地报告评分。采用这种连续评分方法，患者在运动期间报告的呼吸困难评分数量是每分钟离散评分的两倍。基于日常生活活动和运动测试的患者报告的呼吸困难提供了不同但互补的信息。
