Amirav I, Dowdeswell R, Webster T, Plit M
Department of Medicine, J. G. Strijdom Hospital, Johannesburg, South Africa.
Chest. 1993 Jul;104(1):171-4. doi: 10.1378/chest.104.1.171.
The effects of exercise on asthmatic airway caliber are well recognized. Only a few studies, however, evaluated the effects of prior exercise on asthmatic airway reactivity. Eight asthmatic children (ages 10 to 16 years; mean, 12) performed histamine inhalation tests on three occasions assigned in random order: (1) control; (2) 40 to 60 min after exercise (6 min ergometer cycling) done while breathing cold dry (CD) air (temperature = -13 degrees C, relative humidity = 0 percent); and (3) 40 to 60 min after exercise done while breathing warm humid (WH) air (temperature = 33 degrees C, relative humidity = 100 percent). While there was a marked exercise-induced bronchoconstriction (EIB) in the CD test with a postexercise fall in FEV1 of 39.2 +/- 8 percent (mean +/- SEM), there was no EIB in the WH test (4.6 +/- 2 percent). There was no difference, however, in the geometric mean histamine concentration required to produce a 20 percent fall in FEV1 (PC20) among the CD, WH, and control tests (0.52 mg/ml, 0.60 mg/ml, and 0.55 mg/ml, respectively). Airway reactivity in asthmatic children is not influenced by a prior exercise challenge, independent of the conditions of the inspired air during the exercise. Moreover, exercise per se, regardless of development of EIB, does not change the reactivity.
运动对哮喘患者气道管径的影响已得到充分认识。然而，仅有少数研究评估了先前运动对哮喘患者气道反应性的影响。八名哮喘儿童（年龄10至16岁；平均年龄12岁）按随机顺序在三种情况下进行组胺吸入试验：（1）对照；（2）在呼吸冷干（CD）空气（温度=-13℃，相对湿度=0%）时进行6分钟测力计骑行运动后40至60分钟；（3）在呼吸温暖潮湿（WH）空气（温度=33℃，相对湿度=100%）时进行运动后40至60分钟。在CD试验中存在明显的运动诱发支气管收缩（EIB），运动后第一秒用力呼气量（FEV1）下降39.2±8%（平均值±标准误），而在WH试验中无EIB（4.6±2%）。然而，在CD、WH和对照试验中，使FEV1下降20%所需的组胺几何平均浓度（PC20）并无差异（分别为0.52mg/ml、0.60mg/ml和0.55mg/ml）。哮喘儿童的气道反应性不受先前运动激发的影响，与运动期间吸入空气的条件无关。此外，运动本身，无论是否发生EIB，均不会改变反应性。
