Asthma

Question 1

What is asthma characterised by?

Answer 1

recurrent episodes of dyspnoea, cough, and wheeze caused by reversible airway obstruction

Question 2

What are the 4 main symptoms of asthma?

Answer 2

• intermittent dyspnoea
• wheeze
• cought (often nocturnal)
• sputum

Question 3

What features increase the probaility of asthma?

Answer 3

• Wheeze, SOB and chest tightness
• Diurnal variation
• Response to exercise, allergen, cold air
• Symptoms after aspirin or b-blocker
• History of atopy
• Family history atopy/asthma
• Widespread wheeze heard on auscultation
• Unexplained low FEV₁ or PEF
• Unexplained peripheral blood eosinophilia

Question 4

What features lower the probability of asthma?

Answer 4

• Prominent dizziness, light-headedness, tingling
• Chronic productive cough with no wheeze
• Normal examination when symptomatic
• Change in voice
• Symptoms with colds only
• Significant smoking history (>20 pack year)
• Cardiac disease
• Normal PEF when symptomatic

Question 5

What are the main signs of asthma?

Answer 5

• Tachypnoea
• Audible wheeze
• Hyperinflated chest
• Hyper-resonant percussion notes
• Decreased air entry
• Widespread, polyphonic wheeze

Question 6

What are the core features of a severe asthma attack?

Answer 6

• Inability to complete sentences in one breath
• Pulse >110bpm
• Respiratory Rate >25/min
• PEF = 33-50% predicted or best

Question 7

What are the core features of a life-threatening asthma attack?

Answer 7

• PEF <33% predicted or best
• Silent chest, cyanosis, feeble respiratory effort
• Arrhythmia or hypotension
• Exhaustion, confusion or coma
• ABGs
  
  • Normal/high P_aCO₂ >4.6kPa
  • P_aO₂ <8kPa, or SpO₂ <92%

Question 8

What tests should be performed in acut asthma?

Answer 8

• PEF
• Sputum culture
• FBC
• U&E
• Blood Cultures
• ABGs
• CXR

Question 9

What tests should be performed to monitor chronic asthma?

Answer 9

• PEF
• Spirometry - obstructive defect
• CXR - hyperinflation
• Skin prick test - identify allergens
• Histamine or metacholine challenge
• Aspergillus serology

Question 10

What are the alternative differentials to asthma?

Answer 10

• Pulmonary oedema (‘cardiac asthma’)
• COPD
• Large airway obstruction (foreign body, tumour)
• SVC obstruction (wheeze/dyspnoea not episodic)
• Pneumothorax
• PE
• Bronchiectasis
• Obliterative bronchiolitis (suspect in elderly)

Question 11

What is the presentation of acute severe asthma?

Answer 11

acute breathlessness and wheeze

Question 12

What are the Dx when a patient presents with acute asthma?

Answer 12

• Acute infective exacerbation of COPD
• Pulmonary oedema
• Upper respiratory tract obstruction
• Pulmonary embolus
• Anaphylaxis

Question 13

What investigations should be carried out when a patient presents with acute severe asthma?

Answer 13

• PEF – but may be too ill
• ABG – if saturations <92% or life-threatening features
• CXR - if suspicion of pneumothorax, infection of life-threatening attack
• FBC
• U&E

Question 14

What is the immediate management of acute severe asthma?

Answer 14

• Rapid treatment and reassessment is key
• Salbutamol nebulised with oxygen and give prednisolone 30mg PO
• If PEF remains <75% repeat salbutamol; add ipratropium
• Monitor oxygen saturation, HR and RR
• Admit all with severe features not responding to initial treatment or with life threating features

Question 15

What are the main drugs used in the treatment of acute asthma?

Answer 15

• salbutamol
• hydrocortisone and prednisolone
• Aminophylline

Question 16

What lifestyle alterations should be considered in the treatment of chronic asthma?

Answer 16

• Help quit smoking
• Avoid precipitants
• Weight loss (if overweight)
• Check inhaler technique
• Teach use of peak flow meter to check PEF twice a day