Asthma

Question 1

Define asthma

Answer 1

• Chronic inflammatory disease of the airways
• Reversible airway obstruction (either spontaneous or with treatment)
• Increases airway responsiveness

Question 2

What are the differentials for a wheeze?

Answer 2

Acute asthma exacerbation
Bronchitis
Pulmonary oedema
PE
GORD
Foreign body
Allergy
Hyperventilation
Cardiac disease 
COPD

Question 3

Describe the immune response in asthma

Answer 3

Inflammatory reaction to a stimulus with infiltration by:
- eosinophils
- Th2 lymphocytes
- mast cells
- histamine
- leukotrienes
- prostaglandins
Cytokines cause an amplification of the response. Increased mucus production by goblet cells
Smooth muscle proliferation and hyperplasia
Mucus plugging can occur in serious cases, causing fatal and sometimes severe asthma.

Question 4

How can the severity of an asthma exacerbation be characterised?

Answer 4

Mild
Moderate
Severe
Life threatening
Near fatal

Question 5

How would you define mild asthma?

Answer 5

No features of severe asthma

Peak expiratory flow rate is >75%

Question 6

How would you define moderate asthma?

Answer 6

No features of severe asthma

PEFR: 50-75%

Question 7

How would you define severe asthma?

Answer 7

PEFR 33-50% of predicted value
Cannot complete sentences in one breath
Respiratory rate > 23/min
Heart rate > 110 bpm

Question 8

What is the treatment for an acute asthma attack?

Answer 8

ABCDE
Oxygen - aim for 94-98%
ABG if sats

Question 9

What extra management can you give with severe asthma attack?

Answer 9

Nebulised ipratropium bromide 500 micrograms

Back to back salbutamol (2.5-5mg)

Question 10

What extra management can you give with a near fatal or life threatening asthma attack?

Answer 10

Urgent ITU/anaesthetists assessment
Urgent portable CXR
IV aminophylline
Consider IV salbutamol if nebuliser is ineffective

Question 11

What are the criteria for safe discharge after an asthma exacerbation?

Answer 11

PEFR > 75%
Stop regular nebulisers for 24 hours before discharge
Inpatient asthma nurse review
Provide asthma action plan with PEFR values
5 days of oral prednisolone
GP follow up within 2 working days
OPD resp clinic follow up within 4 weeks

Question 12

What is a particular inflammatory mediator which can be targeted against with asthma?

Answer 12

Eosinophils - the eosinophillic inflammation can respond well to steroids

Question 13

Give some DDX of eosinophillia

Answer 13

Asthma/ COPD
Hayfever
Allergic bronchopulmonary aspergillosis
Drugs
Churg-Strauss / vasculitis 
Eosinophilic pneumonia
Parasites
Lymphoma
SLE
Hypereosinophillic syndrome

Question 14

Give some trigger factors for asthma

Answer 14

Smoking 
URTI (particularly viral infections)
Allergens
Exercise
Occupational irritants
Pollution
Drugs - aspirin, beta blockers
Food and drink - dairy produce, alcohol, orange juice
Stress

Question 15

What are some characteristic findings in the history of someone with asthma?

Answer 15

Associations/triggersDiurnal varianceHayfever and eczema

Question 16

What is the drug ladder for asthma treatment?

Answer 16

1 - SABA PRN
2 - SABA + Low dose inhaled steroid (beclometasone)
3 - SABA + corticosteroid + LABA e.g. salmeterol
4 - Increase steroid, add 4th drug e.g. theophylline, LR antagonist
5 - Add PO steroid tablet

Question 17

What things do you need to ask about if you suspect asthma?

Answer 17

Triggers
Diurnal variation
Other atopy conditions
Pets
Asbestos
Occupation

Question 18

Define allergic bronchopulmonary aspergillosus

Answer 18

A condition where there is an exaggerated immune reaction to the aspergillus fungus

Question 19

Who gets allergic bronchopulmomary aspergillosus?

Answer 19

Asthma patients

Cystic fibrosis patients

Question 20

How would you define life-threatening asthma?

Answer 20

Any one of:

- PEFR

Question 21

How would you define near fatal asthma?

Answer 21

Any one of:

- PEFR