Figure 1. Changes in lung function in subjects developing HAPE and in healthy controls.

FVC (upper panel), closing volume above RV (middle panel) and DLCO adjusted for PIO₂ (lower panel), all expressed in percent of the value at 490 m. HAPE  =  subjects subsequently developing HAPE, controls  =  subjects not developing HAPE; first and last day at 4559 m  =  values measured on the day of arrival and either on the last day before clinically overt HAPE occurred, or on day 3 in controls. *P<0.05 vs. 490 m. **P<0.05 vs. controls.