lung volume

Question 1

measure diff lung V & capacities via

Answer 1

LFT lung function test

Question 2

what is tidal volume

Answer 2

volume of air inspired and expired during 1 cycle of quiet/normal respiration

Question 3

normal tidal volume

Answer 3

500ml/min (300-800ml/min)

Question 4

how to estimate a pt’s tidal volume (when put them on machanical ventilation)

Answer 4

multiply body weight by 7ml/kg

Question 5

Adequate Tidal volume is needed to maintain ____ and ___ clearance

Answer 5

maintain oxygenation; CO2 clearance

Question 6

minute volume/ventilation (MV)

Answer 6

volume of gas breathed in and out per min

Question 7

equation for MV

Answer 7

MV = RR x TV

Question 8

normal MV; COPD and why

Answer 8

5-7L/min; 9L/min bc increase RR

Question 9

inspiratory reserve volume (IRV)

Answer 9

additional air that can be inspired voluntarily after a normal TV

Question 10

normal IRV

Answer 10

3.1L

Question 11

what is IRV vital for

Answer 11

effective cough

Question 12

min peak cough flow L/min

Answer 12

160-200 L/min

Question 13

​​Adequate IRV is required to sustain increased levels of ____ or to ____

Answer 13

activity/exercise; take a deep breath

Question 14

What is IRV determined by?​

Answer 14

inspiratory muscle strength (neuro)
effort (fatigue, alcohol)
skeletal abnormalities
starting point
other factors (pain, anxiety, external limitation)

Question 15

Expiratory reserve volume ERV

Answer 15

amount of air that can be breathed forcefully out after normal expiration

Question 16

normal ERV

Answer 16

1.2L

Question 17

residual volume (RV)

Answer 17

air that remains in the lungs after maximal expiration

Question 18

function of RV

Answer 18

prevent lung collapsing at low TV - avoiding large inspiratory effort

Question 19

normal RV

Answer 19

1-1.2L

Question 20

An increase can occur in obstructive lung disease (COPD), due to

Answer 20

air trapping/hyperinflation or aging ​

Question 21

inspiratory capacity IC

Answer 21

max amount of air that can be inspired in one go

Question 22

IC = __+__

Answer 22

TV+ IRV

Question 23

normal IC

Answer 23

3.6L

Question 24

functional residual capacity (FRC)

Answer 24

amount of air that remains in the lungs after Tidal expiration

Question 25

FRC = _+_

Answer 25

RV +ERV

Question 26

function of FRC

Answer 26

Essential to protect alveoli from collapsing at end of expiration – can happen below a certain level (called closing volume)​

Question 27

changes in lung volumes b//w supine and standing ERV increase/decrease? IRV increase/decrease? FRC increase/decrease?

Answer 27

ALL decrease

Question 28

vital capacity

Answer 28

total amount of air that can be exhaled after a full inspiration

Question 29

VC = __+__+__

Answer 29

TV+ IRV +ERV all under conscious control

Question 30

normal VC

Answer 30

3-5L

Question 31

VC less than 1L = patient unable to maintain spontaneous ___& would need support with ___

Answer 31

ventilation; ventilation e.g. mechanical ventilator

Question 32

total lung capacity (TLC)

Answer 32

total amount of air in the lungs after max inspiration

Question 33

TLC = __+__+__+__

Answer 33

TV+IRV+ERV+RV

Question 34

factors affecting lung volume (7)

Answer 34

obesity age sex muscle training respiratory disease smoking status ethnicity

Question 35

restrictive vs obstrictive lung disease

Answer 35

R: reduce lung volume, difficulty expanding during inhalation O: difficulty exhaling, lose elasticity and ability to recoil

Question 36

Restrictive disease (up/down) TV IRV ERV RV TLC

Answer 36

decrease decrease decrease/increase decrease decrease

Question 37

obstructive disease TV IRV ERV RV TLC

Answer 37

increase increase/decrease decrease increase increase

Question 38

spirometry ___ manoeuvre tell us __ and ___ air comes out of out lungs benefits(3) function differentiates? monitor (2)

Answer 38

forced how much and how fast affordable, quick and easy differentiates restrictive vs obstructive lung disease disease progression and effectiveness of certain treatments

Question 39

normal peak flow

Answer 39

300-600l/min

Question 40

FVC forced vital capacity

Answer 40

volume of gas that can be exhaled after full inspiration as quickly as possible

Question 41

normal FVC

Answer 41

3-6L

Question 42

normal FEV1 is ___% of FVC

Answer 42

80%

Question 43

FEV1 predicted is

Answer 43

FEV1 of the pt divided by the average FEV1 of a person with same age, height, sex, weight, ethnicity

Question 44

obstructive disorder FEV1 ? FVC ? FEV/FVC ratio ?

Answer 44

FEV1 reduced (<80% predicted normal) FVC reduced, but to a lesser extent that FEV1 FEV/FVC ratio reduced; <0.7

Question 45

normal FEV1/FVC ratio

Answer 45

0.7-0.8

Question 46

restrictive disorder FEV1 ? FVC ? FEV/FVC ratio ?

Answer 46

reduce or normal (<80% predicted normal) reduced normal or up to 1 (> 0.7)

Question 47

COPD STAGE (FEV1% predicted) mild > 80 moderate 50-79 severe 30-49 very severe <30

Answer 47

> 80 50-79 30-49 <30