Fig. 4

Change of SpO₂ in different groups during the 6 h of hypoxic exposure. After hypoxic exposure, SpO₂ reached its minimum at 1-h hypoxia. At 6-h hypoxia, Acetazolamide and Combined group showed significantly higher SpO₂ than the other groups. Data are mean with SD. ^*P < 0.05, ^**P < 0.01, ^***P < 0.001, ^****P < 0.0001 vs. Control group