Why does reduced alveolar ventilation cause hypoxemia more readily than reduced alveolar perfusion?

💡 Explanation

Hypoxemia is more pronounced with decreased ventilation because a ventilation-perfusion mismatch dramatically curtails oxygen uptake; ventilation dictates alveolar oxygen levels, therefore a reduction more directly impairs oxygen loading into the blood, rather than perfusion issues which can be partially compensated by increased extraction or regional adjustments.

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