Ventilation/Mechanics II

Question 1

Expiratory Reserve Vol (ERV) is?

Answer 1

vol exhaled after normal expiration

~1000ml

Question 2

Residual Vol (RV) is?

Answer 2

lung vol remaining after max expiration
~1200ml
measure w/ He dilution method

Question 3

Vital Capacity (VC) is?

Answer 3

difference b/w total lung capacity and residual vol

~4500ml

Question 4

Vital Capacity eqn

Answer 4

VC = TLC - RV

Question 5

Functional Residual Capacity (FRC) is?

Answer 5

volume of lungs at rest following normal expiration,
“fxn” of opposing forces of lungs and chest wall

expiratory reserve (useable) and residual volume (not useable)
~2200ml

FRC = ERV + RV

Question 6

Total Lung Capacity (TLC) eqn?

Answer 6

TLC = VC + RV

~5700ml

Question 7

Restrictive Lung Disease results in?

Answer 7

↓ compliance:
lung and/or chest wall are less distensible

Ѧ higher intrapleural pressure needed for ∆ in vol

lung vol reduced for given respiratory effort

Question 8

Lung volumes in Restrictive Lung Disease?

Answer 8

↓ TLC and ↓ RV (ALL lung vols ↓)

Ѧ RV:TLC ratio doesn’t change

Question 9

Pulmonary Fibrosis is what type of disease?

Answer 9

restrictive lung disease

Question 10

Obstructive Lung Disease causes?

Answer 10

↑ airway resistance

Question 11

Asthma results in?

Answer 11

airway constriction and ↑ mucus

Question 12

Bronchitis results in?

Answer 12

(COPD)

inflamed bronchi, ↑ mucus

Question 13

Emphysema results in?

Answer 13

(COPD)

alveolar degeneration

Question 14

Forced Vital Capacity (FVC) is?

Answer 14

max forced expiration at max inspired vol

Question 15

Forced Expiratory Volume (FEV) is?

Answer 15

forced exp vol at 1 second into expiration

~ 80% of FVC

Question 16

Lung volumes in Obstructive Lung Disease?

Answer 16

TLC normal
RV ↑ (air trapped in exp) -> ↓ VC
ratio RV:TLC ↑

Question 17

FEV/FVC% corrects for?

Answer 17

body size

Question 18

What happens to FEV and FVC in OBSTRUCTIVE disease?

Answer 18

both decrease

Question 19

What happens to FEV and FEV/FVC% in RESTRICTIVE disease?

Answer 19

↓ diameter has greater effect on FEV than FVC:

FEV decreases
FEV/FVC% stays constant or increases

Question 20

FEV is fxn of? (3)

Answer 20

1) lung size
2) elasticity of lungs
3) airway diameter (resistance)

Question 21

Peak Expiratory Flow (PEF) is?

Answer 21

peak flow rate during max effort:
reproducible measure of airflow obstruction,
used to monitor not treat (e.g. asthma)

Question 22

Hysteresis is?

Answer 22

difference between inflation and deflation of the lung

Question 23

Compliance is?

Answer 23

∆V/∆P

Question 24

High compliance means lungs are?

Answer 24

easy to inflate

Question 25

Filling lung w/ saline does what?

Answer 25

eliminates surface tension = huge compliance

Question 26

Surface tension is higher in inflation or deflation?

Answer 26

inflation (surfactant is redistributed)

Question 27

Lung compliance decreased by? (5)

Answer 27

1) higher lung vol
2) pulmonary fibrosis (restrictive dx)
3) pulmonary congestion (blood)
4) surfactant deficiency
5) edema

Question 28

Lung compliance increased by? (3)

Answer 28

1) low lung vol
2) emphysema (loss of elasticity)
3) age

Question 29

FRC affected by changes in what?

Answer 29

compliance

Question 30

Restrictive dx effects FRC how?

Answer 30

decreases compliance ->

decreases FRC

Question 31

Emphysema effects FRC how?

Answer 31

increases compliance (barrel-chested) ->
increases FRC