Obstructive Lung Diseases

Question 1

What three examples of major obstructive lung disease are there?

Answer 1

Asthma

Chronic bronchitis

Emphysema

(COPD being a combination of the last two)

Question 2

What is the definition of asthma?

Answer 2

Words to the effect of:

Disease characterised by an increased responsiveness of the airways to various stimuli and manifested by a widespread narrowing of airways - pharmacologically reversible

Question 3

What is the definition of chronic bronchitis?

Answer 3

Chronic cough productive of sputum most days in at least three consecutive months for more than two consecutive years

Question 4

Why are there complex time restraints on qualification of chronic asthma?

Answer 4

To rule out other diseases such as tuberculosis

Question 5

What is chronic bronchitis often confused with diagnostically?

Answer 5

Chronic bronchial asthma

Question 6

What is the definition of emphysema?

Answer 6

Increase beyond normal size of airspaces distal to the terminal bronchiole arising either from loss of elastic network of lungs without obvious fibrosis

Question 7

What is a terminal bronchiole?

Answer 7

Last conducting vessel before the alveolar sac

Question 8

What are respiratory bronchioles?

Answer 8

Attach alveoli to terminal bronchiole

Question 9

What heart condition can all obstructive lung diseases can cause as a result of right sided ventricular hypertrophy?

Answer 9

Cor pulmonale

Question 10

What is the pathophysiology of cor pulmonale?

Answer 10

Pulmonary hypertension (>25mmHg) causes right ventricular hypertrophy which causes cor pulmonale

Question 11

Describe the prevalence of asthma in children

Answer 11

10-15% have it, most common in males

Question 12

Describe the prevalence of asthma in adults

Answer 12

5-10% have it, more common in females

Question 13

How many deaths per year does asthma cause on average in the UK?

Answer 13

1000

Question 14

What is the key feature of asthma? If it don’t ____ then it ain’t asthma!

Answer 14

Wheeze

Question 15

What are the proven aetiologies of asthma?

Answer 15

Genetic atopy, occupational exposure and lifestyle (smoking e.g.)

Question 16

What are a few possible aetiologies?

Answer 16

Diet, weight and exposure to microbes

Question 17

What is a wheeze? What causes it?

Answer 17

Polyphonic breath sound caused by narrowing of airway

Can be caused b a tumour, inflammation, asthma, infection or aspiration of foreign body

Question 18

What are the symptoms of asthma?

Answer 18

Wheeze
Dyspnoea
Chest tightness
Cough (usually dry but can be productive)

Question 19

List some common triggers of asthma

Answer 19

Exercise
Cold air 
Smoke 
Perfume 
Pets
Grass pollen 
Aspirin 

Not all are mentioned theres lots more

Question 20

What can the varied presentation of asthma indicate daily, weekly and annually?

Answer 20

Daily - potentially worse at night

Weekly - better at weekends indicating an occupational factor

Annually - environmental

Question 21

What is shunt?

Answer 21

Blood moving from one side of the heart to the other through the lungs without being oxygenated

Question 22

What is the normal physiological percentage of shunt?

Answer 22

2-4%

Question 23

What are the key features of past medical history in asthmatics?

Answer 23

Childhood asthma
Eczema
Hay fever
Drugs including inhalers, aspirin and NSAIDs

Question 24

What important features of a social history are there in regard to asthma?

Answer 24

Smoking
Pets
Occupation
Psychological aspects

Question 25

What do FEV1 and FVC represent in vivo?

Answer 25

FEV1 - airway diameter

FVC - lung capacity

Question 26

What tests are used to confirm an obstructive disease profile?

Answer 26

Lung function:

Helium dilution - test for gas trapping

CO gas transfer - to test for adequate gas transfer

Question 27

What investigations are required before beginning treatment of asthma?

Answer 27

Test reversibility to bronchodilators and corticosteroids

Question 28

What is alveolar dead space?

Answer 28

Air in poorly perfused alveoli that doesn’t take part in gas transfer

Question 29

What is anatomical dead space?

Answer 29

Air in conducting airways that doesn’t take part in gas transfer

Question 30

What is the distinguishing feature of COPD from asthma?

Answer 30

COPD is non-reversible

Question 31

What pharmacological agents are available for the treatment of asthma?

Answer 31

• Bronchodilators (SABA, LTRA, Theophylline)

- Corticosteroids (inhaled or oral)

Question 32

What two types of inhalers are there?

Answer 32

Pressurised metered dose and dry powder

Question 33

Outline the stepwise approach to asthma treatment§

Answer 33

1. Add SABA
2. Add inhaled corticosteroid
3. Add LTRA and refer to specialist
4. Oral steroid