|Subjects||PaO2 mmHg||PaCO2 mmHg||PA–aO2 mmHg|
Analysis of arterial blood obtained from a femoral artery a few hours after arrival at the Margherita hut (Monte Rosa, Italy) in subjects with no acute mountain sickness (AMS), mild AMS (score 2–3 points according to Hackett et al. ), moderate-to-severe AMS (>3 points) or high-altitude pulmonary oedema (HAPE) (verified using chest radiography). PaO2: arterial oxygen tension; PaCO2: arterial carbon dioxide tension; PA–aO2: alveolar–arterial oxygen tension difference. *: p<0.05, compared with mild and no AMS; ***: p<0.001, compared with all groups. Data from .