Wheeze

Question 1

What is wheeze?

Answer 1

Wheeze is the typically high-pitched sound produced by flow through a partially obstructed small airway.

Question 2

Briefly describe the clinical characteristics of wheeze

Answer 2

Associated with prolongation of the expiratory phase of the breathing cycle, as airway diameter contracts further during expiration, leading to trapped air (dynamic hyperinflation).

Typically, high-pitched sound- the pitch can help indicate the size of airway obstructed.

Typically polyphonic (e.g. in asthma) but monophonic wheeze may indicate single airway obstruction (e.g. FB) versus multiple airways.

Associated crepitations may occur when significant airway oedema is present (commoner in infants with bronchiolitis).

Question 3

Give differentials for wheeze

Note: intrinsic change causing lower airway obstruction

Answer 3

• Asthma
• Bronchiolitis
• Bronchitis and bronchiectasis
• CF or primary ciliary dyskinesia (PCD)
• Airway haemangioma/polyps
• Bronchomalacia

Question 4

Give differentials for wheeze

Note: extrinsic lower airway compression

Answer 4

• Lung parenchyma
  
  • Pneumonia, pulmonary oedema and bronchogenic cyst
• Vascular
  
  • Enlarged left atrium compressing left main stem bronchus and pulmonary artery vascular ring
• Lymphatic
  
  • Enlarged hilar lymph nodes
• Chest deformity
  
  • Scoliosis

Question 5

Give differentials for wheeze

Note: intraluminal lower airway obstruction

Answer 5

• Aspiration of food or milk from GOR
• Foreign body inhalation
• Mucus, pus and blood