Pulm circulation

Question 1

Pulmonary circulation:

characteristics

Answer 1

Low resistance,

high compliance

Question 2

PO2 and PCO2 on pulm and systemic circulation

Answer 2

The opposite effect on pulm and systemic circulation

Question 3

Low in PAO2

Answer 3

Hypoxic vasoconstriction that shifts blood away from poorly ventilated regions of lung to well-ventilated regions of lung.

Question 4

Perfusion limited

Answer 4

O2 (normal health), CO2, N2O

Gas equilibrates early along the length of capillaries.
Diffusion can be increased only if blood flow increases.

Question 5

Diffusion limited

Answer 5

O2 (emphysema, fibrosis) and CO

Gas does not equilibrate by the time blood reaches the end of the capillary.

Question 6

Consequence of pulm HTN

Answer 6

Cor pulmonale and subsequent RV failure

JV distension, edema, hepatomegaly

Question 7

Diffusion

Answer 7

Vgas=A/Tx Dk(P1-P2)
A=area
T=thickness
Dk(P1-P2) difference in partial pressure

A=decreased in emphysema
T= increased in pulm fibrosis