Changes in pulmonary PV characteristics of human subjects at an altitude of 5,366 m

We measured lung mechanics in seven young adults at 90 m and again after 9-30 days of exposure to 5,366 m on the summit plateau of Mt. Logan. Increases in peak expiratory flow (by 20%, P less than 0.05) and decreases in total pulmonary resistance (by 30%, P less than 0.02) were consistent with the reduced gas density at high altitude. However, forced expiratory volume in 1 s decreased in four of the seven subjects, suggesting an increase in …