08.13 - Blood Flow, Ventilation-Perfusion (Leffler) - Question

Question 1

Ratio of change in pressure to change in blood flow in pulmonary circulation

Answer 1

Greater than 1:1 –> Blood flow change is more than pressure change causing it

Question 2

Blood flow in base vs apex

Answer 2

Blood flow increases from apex to base of lungs

Question 3

Vascular resistance in base vs apex of lung

Answer 3

Vascular resistance decreases from apex to base

Question 4

Pressure in base vs apex of lung

Answer 4

Pressure increases; Pressure drop increases from apex to base

Question 5

PA vs Pa vs Pv in top third of lung

Answer 5

PA>Pa>Pv

Question 6

PA vs Pa vs Pv in middle third of lung

Answer 6

Pa>PA>Pv

Question 7

PA vs Pa vs Pv in bottom third of lung

Answer 7

Pa>Pv>PA

Question 8

Blood pressure in base vs apex

Answer 8

Blood Pressure increases from apex to base

Question 9

Where does fluid move out of lungs?

Answer 9

Where pressure is highest –> Base of lungs –> Edema in CHF

Question 10

Which part of lung becomes edematous in CHF

Answer 10

Base, highest pressure

Question 11

Lung arteries and arterioles constrict in response to

Answer 11

Hypoxia, Hypercapnia, Acidosis

Question 12

Effect of Hypoxia on Lung arteries and arterioles

Answer 12

Constrict

Question 13

Effect of Hypercapnia on Lung arteries and arterioles

Answer 13

Constrict

Question 14

Cause of chronic pulmonary hypertension

Answer 14

Hypoxia –> Increased Pulmonary Vascular Resistance

Question 15

VA/Q ___ from lung apex to base

Answer 15

decreases

Question 16

The greater the VA/Q, the ___ the O2, and the __ the CO2

Answer 16

Higher O2, Lower CO2

Question 17

Compliance at top of lung vs bottom

Answer 17

Lower compliance at top –> Less change in volume for given change in pressure

Question 18

Which part of lung has highest compliance

Answer 18

Bottom –> Greater change in volume for given change in pressure

Question 19

Change in VA/Q from bottom to top of lung

Answer 19

Increase

Question 20

Change in Q and VA from base to apex of lung

Answer 20

Both decrease, but Q decreases more rapidly

Question 21

Which part of lung has highest partial pressure of O2

Answer 21

Top –> Hyperventilated –> Blood flow much lower than ventilation

Question 22

Which part of lung has lowest partial pressure of O2

Answer 22

Base –> Hypoventilated

Question 23

Which part of lung has higher partial pressure of CO2

Answer 23

Base

Question 24

Hypoperfused by normally ventilated =

Answer 24

High PO2

Question 25

Hypoventilated by normally perfused =

Answer 25

Low PO2

Question 26

T/F: VA/Q mismatch or shunt can both increase PaCO2

Answer 26

False, neither

Question 27

T/F: Hypoxemia can be caused by VA/Q mismatch

Answer 27

TRUE

Question 28

T/F: Hypoxemia can be caused by Shunt

Answer 28

TRUE