Alveolar Ventilation

Question 1

normal DLCo

Answer 1

20-30 mL

Question 2

diseases with normal DLCO

Answer 2

asthma, chronic bronchitis, neuromuscular disease, chest wall deformities

Question 3

diseases with decreased dlco

Answer 3

pulmonary emboli, fibrosis, emphysema, pulmonary edema

Question 4

diseases with increased dlco

Answer 4

pulm heme, LtoR shunt, asthma

Question 5

where is ventilation highest and why

Answer 5

bottom of lung, gravity

Question 6

where is pressure highest in lung

Answer 6

less negative toward bottom due to gravity

Question 7

relationship between compliance and ventilation

Answer 7

proportional

Question 8

In standard atm, what’s ratio of O2 and N2

Answer 8

O2: 21%
N2: 79%

Question 9

what is O2/CO2 exchange ratio

Answer 9

250 ml O2 to 200 ml of CO2 (+50 H2O)

Question 10

Rate of Total Ventilation (min. vent)

Answer 10

V*= Freq x Vt

Question 11

Alveolar Vent per minute

Answer 11

Va*= Freq(Vt - Vd)

Question 12

Respiratory Exchange Ratio

Answer 12

R= CO2 output/O2 input
R= 0.8

Question 13

Alveolar ventilation depends on

Answer 13

Respiratory Rate, Tidal Volume, Dead Space Volume

only the vol of air participating in exchange

Question 14

anatomical dead space

Answer 14

volume of air left in conducing airways

~150 mL

Question 15

alveolar dead space

Answer 15

vol of air left in unperfused alveoli

lung disease, ventilation-perfusion mismatch

Question 16

Physiological Dead Space

Answer 16

summation of alveolar and anatomical dead spaces

Question 17

elevated Vdtotal

Answer 17

due to PE, or tubes

Question 18

Respiratory acidosis

Answer 18

Va* halved, APCO2 and aPCO2 will double

Question 19

Respiratory alkalosis

Answer 19

Va* doubled, PACO2 and PaCO2 will halve

Question 20

alveolar ventialiation and BMR

Answer 20

proportional