Asthma

Question 1

what is asthma?

Answer 1

type of obstructive lung disease characterised by paoxysmal and reversible airway bronchoconstriction, as a result of inflammation of the respiratory airways and bronchial hyperresponsiveness

Question 2

what is the atopic triad?

Answer 2

• asthma
• allergic rhinitis
• atopic eczema

Question 3

what type of hypersensitivity reaction is asthma?

Answer 3

type 1 hypersensitivity reaction

Question 4

what does airway inflammation lead to?

Answer 4

airway remodelling

Question 5

what is airway remodelling characterised by?

Answer 5

• bronchial smooth muscle hypertrophy
• bronchoconstriction
• mucous gland hypertrophy
• vasodilation and increased vascular permeability

Question 6

what symptoms are associated with asthma?

Answer 6

• wheeze
• dyspnoea
• cough - may be nocturnal
• chest tightness
• diurnal variation = worse in mornin
• worse following exercise or NSAIDs/beta-blockers

Question 7

what is a sign on examination of severe disease?

Answer 7

silent chest

Question 8

what are the signs of a severe attack?

Answer 8

• inability to speak in complete sentences
• respiratory rate >25
• peak flow 33-50% predicted

Question 9

what are the signs of a life-threatening attack?

Answer 9

• silent chest
• confusion
• bradycardia
• cyanosis
• exhaustion

Question 10

what are the examination findings in asthma?

Answer 10

• tachypnoea
• hyperinflated chest
• hyper-resonance on chest percussion
• decreased air entry
• wheeze

Question 11

what investigations are carried out in chronic asthma?

Answer 11

• peak flow
• fractional exhaled nitric oxide (FeNO)
• spirometry

Question 12

what is the predicted value for peak flow in asthma?

Answer 12

variability >20% predicted

Question 13

what is the predicted results from a fractional exhaled nitric oxide (FeNO) in asthma?

Answer 13

• > 40 ppb in adults
• > 35 ppb in children

Question 14

what are the expected spirometry results in asthma?

Answer 14

• low FEV1
• preserved FVC
• FEV1/FVC <0.7
  obstructive spirometry which can be reversed on administration of a bronchodilation

Question 15

what investigations should be performed in acute asthma?

Answer 15

• ABG
• routine blood tests - to check for precipitating causes
• chest x-ray - to check for precipitating causes

Question 16

what can ABG results demonstrate in an acute asthma attack?

Answer 16

type 2 respiratory failure (low PaO2 and high PaCO2)

sign of life-threatening attack

Question 17

what is the management for an acute asthma attack?

Answer 17

1. ensure a patent airway
2. oxygen saturations of 94-98%
3. nebulisers = salbutamol, ipratropium
4. steroids = oral prednisolone or IV hydrocortisone (if severe)
5. IV magnesium
6. IV aminophylline
7. intensive care

Question 18

what non-pharmalogical management can be undertaken in chronic asthma?

Answer 18

• smoking cessation
• avoidance of precipitating factors
• review inhaler technique

Question 19

what is step 1 of asthma management?

Answer 19

short-acting inhaled B2-agonist

salbutamol

Question 20

what is step 2 of asthma management?

Answer 20

low-dose inhaled corticosteroid

if symptoms are presisting at night or >3 times a week

Question 21

what is step 3 of asthma management?

Answer 21

long-acting B2-agonist
no benefit = stop and increase ICS
inadequate benefit = continue and increase ICS

Question 22

what is step 4 of asthma management?

Answer 22

leukotriene receptor antagonist + high-dose steroid + oral B2-agonist

Question 23

what are the asthma mimics?

Answer 23

• acid reflux
• churg-strauss syndrome
• allergic bronchopulmonary aspergillosis (ABPA)

Question 24

what is acid reflux?

Answer 24

acidic contents of the stomach are regurgitated into the oesophagus

Question 25

what can acid reflux lead to?

Answer 25

gastro-oesophageal reflux disease (GORD)

Question 26

what are the risk factors for acid reflux?

Answer 26

• obesity
• smoking
• alcohol
• medications that relax the lower oesophageal sphincter tone (e.g. calcium-channel blockers)

Question 27

what are the symptoms of GORD?

Answer 27

• dry cough
• wheeze
• shortness of breath
• hoarse voice
• dental erosion
• chest pain

Question 28

what is the management for GORD?

Answer 28

• antacids (e.g. gaviscon)
• protein pump inhibitors (e.g. omeprazole)
• H2 blockers (e.g. ranitidine)

Question 29

what is churg-strauss syndrome?

Answer 29

granulomatous vasculitis associated with adult-onset asthma and eosinophilia

Question 30

what conditions are associated with churg-strauss syndrome?

Answer 30

• sinusitis
• asthma
• purpura
• peripheral neuropathy

Question 31

what serology tests are positive in churg-strauss syndrome?

Answer 31

• pANCA +ve
• raised IgE

Question 32

what is the management of churg-strauss syndrome?

Answer 32

• steroids
• immunological agents
• treatment-resistant = rituximab

Question 33

what is allergic bronchopulmonary aspergillosis (ABPA)?

Answer 33

type I and II hypersensitivity reaction to aspergillus fumigatus

Question 34

what conditions is ABPA associated with?

Answer 34

• cystic fibrosis (~25%)
• asthma (~1%)

Question 35

how does ABPA present?

Answer 35

immediate reaction upon exposure of the skin to aspergillus fumigatus antigens

Question 36

what is the management of ABPA?

Answer 36

• prednisolone regimen
• itraconazole
• bronchodilators

Question 37

what is the diagnostic criteria for moderate asthma?

Answer 37

• increse symptoms
• PEFR of 50-75%

Question 38

what is the diagnostic criteria for severe asthma?

Answer 38

• PEFR 33-50%
• RR >= 25
• HR >= 110

at least one of these features with no features of life-threatening

Question 39

what is the diagnostic criteria for life-threatening asthma?

Answer 39

• PEFR <33%
• stats <92%
• PaO2 <8 kPa
• normal CO2
• poor respiratory effort
• altered GCS/agitation
• hypotension