Lung Function Tests

Question 1

what is the purpose of lung function tests

Answer 1

used to help establish a diagnosis in lung disease

Question 2

what types of lung disease do lung function tests particularly help in diagnosing and distinguishing between

Answer 2

obstructive and restrictive lung disease

Question 3

what is a spirometry test

Answer 3

test used to establish objective measures of lung function

Question 4

what does a spirometry test consist of

Answer 4

involves different breathing exercises into a machine that measures volume of air and flow rates, and produces a report

Question 5

what is reversibility testing in relation to spirometry

Answer 5

involves giving a bronchodilator (e.g. salbutamol) prior to repeating spirometry test to see if this has an impact on the results

Question 6

what is FEV1

Answer 6

forced expiratory volume in 1 sec

• the amount of air a person can exhale asap in 1 sec

Question 7

what is FEV1 a measure of

Answer 7

the ability of air to freely flow out of the lungs

Question 8

when will FEV1 be reduced

Answer 8

• any obstruction to air flow out of lungs

- obstructive disease

Question 9

what is FVC

Answer 9

forced vital capacity

• the total amount of air a person can exhale after a full inhalation

Question 10

what is FVC a measure of

Answer 10

the total volume of air that the person can take in to their lungs

Question 11

when will FVC be reduced

Answer 11

• any restriction on capacity of lungs

- restrictive disease

Question 12

what spirometry result can obstructive lung disease be diagnosed from

Answer 12

FEV1:FVC ratio <75%

FEV1 is less than 75% of FVC

Question 13

outline if there is difficulty on inspiration or expiration w/ obstructive/restrictive lung disease

Answer 13

obstructive –> expiration

restrictive –> inspiration

Question 14

give examples of obstructive lung disease

Answer 14

• COPD
• asthma
• bronchiectasis
• CF

Question 15

how can you test the reversibility of an obstruction in the lungs

Answer 15

giving a bronchodilator e.g. salbutamol

Question 16

is lung obstruction reversible in asthma

Answer 16

typically yes

Question 17

is lung obstruction reversible in COPD

Answer 17

typically no

Question 18

what would the spirometry result be in restrictive lung disease

Answer 18

• FEV1 and FVC equally reduced

- FEV1:FVC ratio >75%

Question 19

describe restrictive lung disease

Answer 19

restriction in ability of lungs to expand and take air in

Question 20

what is obstruction normally due to in asthma

Answer 20

obstruction due to narrowed airway due to bronchoconstriction

Question 21

what is obstruction normally due to in COPD

Answer 21

chronic airway and lung damage causing obstruction

Question 22

list some causes of restrictive lung disease

Answer 22

• interstitial lung disease
• neurological (e.g. motor neurone disease)
• scoliosis or chest deformity
• obesity

Question 23

what is peak flow

Answer 23

measure of the peak or fastest point of a person’s expiratory flow of air
(can be referred to as peak expiratory flow rate or PEFR)

Question 24

describe how is peak flow measured

Answer 24

• measured using a peak flow meter
• Px stands tall and takes a deep breath in, making a good seal around the device w/ lips
• blow as fast and hard as possible into device
• take 3 attempts and record best result
• results can vary dramatically based on size and age of patient

Question 25

what is peak flow measurement used for

Answer 25

used to demonstrate how much obstruction to airflow is present in the patients lungs

Question 26

how is peak flow result usually recorded

Answer 26

usually recorded as percentage of predicted

Question 27

how do you obtain a predicted peak flow

Answer 27

based on sex, height and age using a reference chart