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What is A mountaineer ascents 18,000 feet in 2 days without supplemental oxygen. At the height of ascent the changes area) ↑ed PaCO2b) ↓ed Barometric pressurec) ↓ed Inspired O2 d) ↓ed PaO2e) ↑ed pH and explain in detail?
At high altitude, the atmospheric pressure is low and partial pressure of O2 in air is low. This results in decreased PaO2, though the fraction of inspired air remains same. Hyperventilation results in CO2 washout and respiratory alkalosis.