Pulmonary gas exchange Flashcards Preview

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Flashcards in Pulmonary gas exchange Deck (6):
1

Perfusion-limited exchange?

 

  • gas equilibrates early along the length of the pulmonary capillary, therefore the partial pressure of the gas in the arterial blood equals that in the alveolar air
  • the only way to increase diffusion of a gas is therefore to increase blood flow

2

Diffusion-limited exchange?

 

  • gas does not equilibrate by the time the blood has reached the end of the pulmonary capillary
  • a partial pressure gradient is therefore maintained between the arterial blood and the alveolar air

3

Examples of perfusion-limited exchange?

  • Oxygen (normal conditions)
  • Nitrous oxide 
  • Carbon dioxide

4

Examples of diffusion-limited exchange?

  • Oxygen (during strenuous exercise) 
  • Oxygen (lung fibrosis)
  • Oxygen (emphysema)
  • Carbon monoxide

5

Mnemonic to remember - Examples of perfusion-limited exchange

CON

arbon dioxide

xygen (normal conditions)

itrous Oxide
 

6

Mnemonic to remember - Examples of diffusion-limited exchange​

COOO

arbon monoxide

xygen (during strenuous exercise) 
xygen (lung fibrosis)
xygen (emphysema)