Lung function and blood gas of rats after different protocols of hypobaric exposure.

High-altitude pulmonary edema (HAPE) is a common disease observed in climbers, skiers and soldiers who ascend to high altitudes without previous acclimatization. Thus, a reliable and reproducible animal model that can mimic the mechanisms of pathophysiologic response in humans is crucial for successful investigations. Our results showed that exposure to 4500 m for 2 days had little influence on lung function or blood gas, and exposure to 6000 m for 2 or 3 days could change lung function and blood gas, but most parameters returned to nearly normal levels within 48 hours. This study indicates that exposure to 6000 m for 3 days may induce evident lung edema and significantly alter lung function and blood gas, which may mimic HAPE in clinical practice. Thus, this animal model of HAPE may be used in future studies on HAPE.