Obstructive and restrictive lung disease

Question 1

What does spirometer measure

Answer 1

Lung volumes

Question 2

By how much should inspiratory reserve and expiratory reserve

Answer 2

Inspiratory reserve is about 2-3L

Expiratory is 1L

Question 3

What should tidal volume be for an 80kg man?

Answer 3

560ml

Question 4

What is vital capacity

Answer 4

Expiratory reserve volume+ tidal volume + inspiratory reserve volume

Question 5

How much should vital capacity be in a healthy young man?

Answer 5

4.8L

Question 6

How much should vital capacity be in a young woman?

Answer 6

3.5L

Question 7

When is peak flow most useful

Answer 7

Most useful as serial measurments to monitor effectiveness of treatment

Question 8

What measures forced expiratory volumes

Answer 8

Vitalograph

Question 9

How do FVC and FEV1 appear in obstructive lung disease

Answer 9

FEV1 reduced due to narrowed airways, FVC normal

FEV1/ FVC ratio reduced

Question 10

How do FVC and FEV1 appear in restrictive lung disease

Answer 10

Both reduced to ratio is maintained

Question 11

What are the parameters used to diagnose obstructive disase in FEV1/FVC ratio

Answer 11

> 70% predicted= normal
61-69% predicted= mild obstruction
45-60%= moderate obstruction
<45%= severe

Question 12

Key feature of obstructive disorder

Answer 12

Reduced peak flow rate

Question 13

Key feature of restrictive disorder

Answer 13

Reduced vital capacity

Question 14

Immediate asthma response?

Answer 14

Inhaled allergen binds to IgE of mast cells

Mast cells release inflammatory mediators producing mucus, bronchoconstriction and oedema

Question 15

Delayed asthma response?

Answer 15

Eosonophils are activated by mast cells and discharge proteins that damage epithelial cells
This damages afferent nerves activating parasympathetic discharge

Question 16

What happens in chronic asthma

Answer 16

Increased mucus secretion but reduced ability to transport it due to damaged epithelium- coughs

Question 17

Pros of spacers

Answer 17

Improve drug penetration

Reduce potential for adverse effects

Question 18

How do nebulizers

Answer 18

Make an inhaled mist of medication- small children/ severe asthma episode

Question 19

Define chronic bronchitis

Answer 19

Chronic productive cough without discernable cause for more than half the time over 2 years

Question 20

Features of chronic bronchitis

Answer 20

Hypertrophy of bronchial glands
Hypersecertion
Mucous plugs

Question 21

How is emphysema classified

Answer 21

Enlargement of airspaces distal to terminal bronchioles
Destruction of lung stroma- bullae
Floppy airways cause obstruction

Question 22

How does smoking link to bronchitis

Answer 22

Irritants damage epithelium
Proliferation of squamous cells
Stimulates mucous gland enlargement

Question 23

How does smoking link to emphysema

Answer 23

Cigarette smoke stimulate polymorphonuclear leucocytes to release serine elastase
Smoke inactivates elastase inhibitor alpha 1 antitrypsin
This lets serine elastase destroy elastic tissue of lung

Question 24

Do steroid improve flow in asthma, COPD or both

Answer 24

Just asthma

Question 25

What restrictive disorders result in loss of volume/ increased recoil of lung

Answer 25

• Pneumonia
• Pneumonthorax
• Atelactasis
• Pulmonary fibrosis

Question 26

What restrictive disorders cause difficulty in production of chest movements

Answer 26

• Pleural thickening

- Neuromuscular weakness

Question 27

What restrictive disorders cause limitation of lung volume externally

Answer 27

• Ankylosing spondylitis

- Kyphoscoliosis

Question 28

What do flow volume loops show

Answer 28

Flow in L/ sec vs lung volume (L)

Question 29

How do flow volume loops appear in obstructive disease

Answer 29

Flow rate is low in relation to lung volume
Expiration ends prematurely because of early airway closure
‘scooped out appearance’

Question 30

How do flow volume loops appear in restrictive lung disease

Answer 30

Tall and narrow