Responses of older men with and without chronic obstructive pulmonary disease to prolonged ozone exposure.

摘要: Abstract We tested responses to ozone (O3) under simulated “worst-case” ambient exposure conditions. Subjects included 9 men who had severe chronic obstructive pulmonary disease (COPD) with subnormal carbon monoxide diffusing capacity (i.e., an emphysemic component) and 10 age-matched healthy men. Each subject was exposed 0.24 ppm O3 clean air (control) in environmentally controlled chamber at 24 °C 40% relative humidity. Exposures were randomized, they occurred 1 wk apart, lasted 4 h. During each half-hour interval, light exercise average ventilation 20 l/min) for 15 min. both control exposures, group mean symptom intensity specific airway resistance (SRaw) increased, whereas forced expiratory performance decreased. The subgroup's arterial oxygen saturation (SaO2) rose slightly, the COPD SaO2 declined during exercise. Group volume s (FEV1.0) significantly expos...