Asthma

Question 1

Which clinical feature must be present for the diagnosis of asthma?

Answer 1

Wheeze.

Question 2

In which gender groups in asthma most common?

Answer 2

Boys and women.

Question 3

Which ‘hits’ can contribute to asthma?

Answer 3

Genes, inherently abnormal lungs, early onset atopy and later exposures such as viruses, exercise and smoking.

Question 4

What are the common symptoms of asthma?

Answer 4

Wheeze, SOB at rest. sooking in of ribs with wheeze, cough (dry, just after falling asleep, exertional).

Question 5

What are common features in the history of an asthma patient?

Answer 5

URTI, FH, eczema, hayfever and food alllergies.

Question 6

What is the main treatment for asthma?

Answer 6

ICS for 2 months.

Question 7

What are the differential diagnoses?

Answer 7

VIW - give salbutamol to differentiate.

Question 8

What are the 3 proven risk factors for asthma?

Answer 8

Genetic risk factors, occupational risk factors and smoking.

Question 9

Describe genetic risk factors for asthma.

Answer 9

Atopy - genetic tendency to develop a disease. Increased IgE response to allergens, food allergies, hay fever and eczema. Strongest risk factor is a family history of atopic disease. 2 groups of genetic associations: il4, il5 and Ige, and airway genes (ADAM33).

Question 10

Describe occupational risk factors for asthma.

Answer 10

10-15% adult onset asthma caused by these.

Question 11

How does smoking increase chances of asthma?

Answer 11

Maternal smoking during pregnancy: lower FEV1, higher wheezy illness, airway responsiveness and change of high asthma severity. Grandmother effect: smoking causes epigenetic changes in the foetus so there is a higher chance of asthma in the child.

Question 12

What other things can cause wheeze other than asthma?

Answer 12

Localised airway obstruction, inspiratory stridor, tumour or foreign body.

Question 13

Which 5 diseases can cause generalised airflow obstruction?

Answer 13

Asthma, COPD, bronchiectasis, bronchiolitis and CF. Asthma is reversible, COPD is not.

Question 14

What affects do B-blockers have on asthma?

Answer 14

Make it worse.

Question 15

What will the FEV1:FVC be in an asthma patient?

Answer 15

Can be normal as asthma symptoms are reversible when given B2-agonists or steroids. If there is an obstruction this will be less than 70% predicted.

Question 16

What separates COPD from asthma?

Answer 16

Reversibility of symptoms when given oral corticosteroids.

Question 17

How is spirometry used in asthma testing?

Answer 17

If obstructed, full pulomnary function tests then test reversibility with B2 agonists then steroids. Normal, peak flow monitoring and bronchial provocation test/NO.

Question 18

Name the essential investigations for asthma.

Answer 18

Looking for evidence of AFO and its reversibility.: spirometry, lung volumes (gas trapping), CO gas transfer, response to bronchodilator (salbutamol), response to ICS (anti-inflammatory), peak flow for 2 weeks (if spirometry normal).

Question 19

How is acute, severe asthma assessed?

Answer 19

Ability to speak, HR, RR, PEF, O2 saturation and arterial blood gases.

Question 20

What is a symptom of near fatal asthma?

Answer 20

Raised PaCO2.

Question 21

What are the goals of asthma treatment?

Answer 21

Minimal symptoms during day/night; minimal need for medication; no exacerbations; no limitation of physical activity; and normal lung function (FEV1 or PEF > 80% predicted or best).

Question 22

How is asthma control measured?

Answer 22

SANE

SABA/week, Absence school/nursery, Nocturnal symptoms/week and Exertional symptoms/week.

Question 23

What are the classes of asthma medications?

Answer 23

SABA, ICS, LABA, Leukotriene receptor antagonists, Theophyllines and oral steroids.

Question 24

Describe the stepwise approach to asthma treatment in CHILDREN.

Answer 24

1) Start with inhaled SABA (spacer/DPI) and monitor. 2) If using SABA/waking up > 3 x/week start on low dose ICS or LABA if under 5. 3) Complicated. Add LABA or > dose of ICS. 4) Under 5’s refer for confirmation of diagnosis, over 5’s increase to > dose ICS. 5) Refer! 6) Psychological/compliance issues - question diagnosis.

Question 25

What does a leukotriene receptor antagonist (LTRA) do?

Answer 25

Blocks inflammation of airways - most effective in those who are highly allergic. Non-steroidal. Montelukast is the only one.

Question 26

What is the advantage of using a spacer?

Question 27

What is the advantage of using a DPI (dry powder inhaler)?

Answer 27

Achieves 20% lung deposition. Quicker, quieter and cheaper than nebuliser.

Question 28

What are the advantages of inhalers?

Answer 28

Small dose of drugs, delivered directly to target organ, onset of effect faster, minimal systemic exposure, systemic adverse effects are less severe/frequent, inhaled drug therapy is painless and relatively comfortable.

Question 29

What is a MDI?

Answer 29

Metered dose inhaler. However, needs co-ordination and so elderly/children/unwell cannot use effectively. Better when used with a spacer. With DPI patients control inhalations.

Question 30

Describe the stepwise approach to asthma treatment in ADULTS.

Answer 30

1) SABA as required (mild intermittent asthma), salbutamol or terbutaline, adverse effects rare with inhaled and common with oral formulations. 2) Add ICS (regular preventer therapy), end in ‘sone’, oral have many side effects. 3) Add LABA or > ICS to 800 mcg, eg. symbicort. 4) > ICS up to 2000 mcg or add LTRA/therphylline/B2 agonist tablet (persistent poor control). 5) Frequent use of oral steroids.

Question 31

Describe the effects of theophylline.

Answer 31

Weak bronchodilator but has many side effects. Narrow therapeutic window and unpredictable metabolism (interacts with many drugs).

Question 32

What is omalizumab?

Answer 32

An anti-IgE mAb for IgE-mediated severe allergic asthma.

Question 33

How is acute mild/moderate asthma treated?

Answer 33

Oral predisolone for 7 days; SABA every 2 hours; assess within 24 hours. Immediate medical help if deteriorating.

Question 34

How is acute severe asthma treated?

Answer 34

Admission to hospital; oral/IV steriods; nebulused bronchodilators (salbutamol/ipratropium); O2 (target SaO2 94-98%); consider IV MgSo4 (Mg sulphate); antibiotics of pneumonia/bacterial infection; CXR and ABG.