alveolar gas equation calculates oxygen content of alveoli

• related: pathophysiology of hypoxia and hypoxemia
• tags: #permanent #pulmonology

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Links to this note

• pathophysiology of hypoxia and hypoxemia
  • alveolar gas equation calculates oxygen content of alveoli
• using Aa gradient to determine reason for hypoxemia
  • Hypoxemia is decreased $O*2$ saturation, which is directly affected by $P*{aO_2}$ (alveolar gas equation calculates oxygen content of alveoli).

Oxygen content of alveoli is dependent on oxygen content of inspired air and mixing of $CO_2$ gas exchange.

• $P_{IO_2}$: inspired air O2 content
• $P_{AO_2}$: alveolar O2 content is lower because of gas exchange
• $P_{aO_2}$: arterial blood content is lower because of shunt
• $S_{aO_2}$: oxygen saturation is directly dependent on arterial oxygen content. Oxygen saturation is percentage of hemoglobin site that's bound with oxygen molecule.