Gas exchange — Flashcards

Flashcard 121: In response to decreased atmospheric oxygen (e.g. high altitude), there is a _____ Pao2

Answer: decreased

Flashcard 122: The partial pressure of carbon dioxide in the alveolar air (PACO2) and arterial blood (PaCO2) is normally approximately _____ mmHg

Answer: 40

Flashcard 123: The lung diffusing capacity (DL) is the equivalent of _____ of the alveolar-pulmonary capillary barrier

Answer: permeability

Flashcard 124: In response to exercise, there is _____ venous O2 content

Answer: decreased

Flashcard 125: What is the typical normal value for anatomic dead space (mL)?_____

Answer: 150 mL

Flashcard 126: Is the A - a gradient normal, increased, or decreased, in response to high altitude? _____

Answer: Normal

Flashcard 127: According to Fick's law, the rate of diffusion of a gas (Vgas) is equal to: _____

Answer: Vgas = (A × D × ΔP) / T

Extra: Fick's Law of Diffusion: - A: Surface Area (e.g., decreased in emphysema) - D: Diffusion coefficient (Solubility / √MW; CO2 diffuses 20x faster than O2) - ΔP: Partial pressure gradient - T: Membrane thickness (e.g., increased in interstitial fibrosis)

Flashcard 128: 2,3-BPG increases under _____ conditions (e.g. high altitude)

Answer: hypoxic

Flashcard 129: The diffusion coefficient (DK) for CO2 is approximately 20x _____ than that of O2

Answer: higher

Flashcard 130: Only _____ gas contributes to the partial pressure of a gas in solution

Answer: free, dissolved