Dasgupta - Diffusion Of Gases Flashcards
The fick’s equation shows that the rate of diffusion of a gas depends on
SA of barrier * diffusion constant * gradient of partial pressure
Divided by
Thickness of barrier
The rate of diffusion is highly impacted by changes in?
Partial pressure
In perfusion limitation, gas diffuses through the membrane well and equilibriate ______
Quickly.
Amount of this gas taken up is determined by how much blood flow there is
You can basically ______ the flow rate along a pulmonary capillary and still have the blood be fully saturated
Triple
Oxygen, _____ and _______ are all perfusion-limited
N2O and CO2
The partial pressure of CO on the blood side is always ____ because of hemoglobin’s high affinity for it
Zero
What limits CO uptake?
Ability of the membrane to transfer CO by diffusion
Diffusion limited
Changes in lung conductance will reflect anything that alters the ability of a lung to exchange gases. Principally ___________ and ___________.
Area available for exchange
Barrier thickness
DLCO is reduced in obstructive diseases becaus of ?
Alveolar simplification and loss of pulmonary capillary structures (SA)
DLCO is reduced in restrictive disease because of ?
Thickening of the alveolar capillary membrane which impairs diffusion
Emphysema, embolus, and alveolar fibrosis cause a _____ in DLCO
Decrease
Interstitial edema, lung resection, asbestosis, and collagen vascular disease cause a ______ in DLCO
Decrease
Anemia, pregnancy, alveolar proteinosis, smokers, and pulmonary hypertension cause a _______ in DLCO
Decrease
Alveoli are filled with protein and phospholipid rich material which causes a drop in DLCO.
Alveolar proteinosis
Bronchitis
Neuromuscular disease
Chest wall deformities
And asthma (sometimes) cause _ _______ in DLCO
No change
