Lung function tests

Question 1

What test is used to establish objective measures of lung function?

Answer 1

Spirometry

Question 2

What does reversibility testing involve?

Answer 2

Giving a bronchodilator prior to repeating a spirometry to see the impact this has on the results.

Question 3

1) What does FEV1 mean?
2) What does FVC mean?

Answer 3

1) Forced expiratory volume in 1 second. This is the amount of air a person can exhale as fast as they can in 1 second
2) Forced vital capacity. This is the total amount of air a person can exhale after a full inhalation

Question 4

In terms of lung function:
1) What does FEV1 measure?
2) What does FVC measure?

Answer 4

1) Ability of air to freely flow out of the lungs
2) Total volume of air that the person can take in to their lungs

Question 5

A reduction in which test - FEV1 or FVC indicates an obstructive condition, and which indicates a restrictive condition?

Answer 5

FEV1 = obstructive
FVC = restrictive

Question 6

How can an obstructive disease be diagnosed with FEV1 and FVC?

Answer 6

If FEV1 is less than 70% of FVC

Question 7

How can a restrictive disease be diagnosed with FEV1 and FVC?

Answer 7

If FEV1 and FVC are equally reduced and FEV1:FVC ratio > 70%

Question 8

Name 2 causes of restrictive lung disease

Answer 8

• Interstitial lung disease
• Neurological (i.e. motor neurone disease)
• Scoliosis or chest deformity
• Obesity

Question 9

What is a peak flow meter useful in demonstrating?

Answer 9

How much obstruction to airflow is present in the patient’s lungs

Question 10

What does TLCO measure, and what is used to measure TLCO?

Answer 10

How well lungs exchange gas. Carbon monoxide

Question 11

Name a cause of a raised TLCO

Answer 11

• Polycythaemia
• Male
• Exercise
• Asthma
• Left-right cardiac shunts
• Pulmonary haemorrhage

Question 12

Name a cause of a decreased TLCO

Answer 12

• Pneumonia
• Pulmonary oedema
• Pulmonary embolism
• Low CO
• Anaemia
• Pulmonary fibrosis
• Emphysema

Question 13

What is the relationship between TLCO and the transfer coefficient?

Answer 13

Transfer coefficient (KCO) = TLCO corrected for lung volume

Question 14

Name a cause of an increased KCO with a normal or reduced TLCO

Answer 14

• Kyphosis/scoliosis
• Pneumonectomy/lobectomy
• Neuromuscular weakness
• Ankylosing of costovertebral joints i.e. ankylosing spondylitis

Question 15

What effect does age have on KCO?

Answer 15

Increases it