Table of Contents
1. Definition
- Wheeze is a high-pitched, musical, continuous sound produced by airflow through narrowed airways, typically during expiration.
- Indicates airway obstruction at any level (from trachea to small bronchi).
2. Initial Assessment
A. ABC Assessment
- Airway: Ensure patency; look for obstruction (secretions, foreign body).
- Breathing:
- Respiratory rate, effort (retractions, nasal flaring, grunting)
- Oxygen saturation (SpO₂)
- Presence and distribution of wheeze
- Work of breathing (mild / moderate / severe)
- Circulation: Heart rate, capillary refill time, BP, color.
B. Severity Assessment
| Severity | Features |
|---|---|
| Mild | Speaking in sentences, SpO₂ > 94%, mild wheeze |
| Moderate | Breathless, feeding difficulty, SpO₂ 90–94% |
| Severe | Cannot talk/feed, SpO₂ < 90%, exhaustion, cyanosis, silent chest |
3. Focused History
| Aspect | Key Points |
|---|---|
| Onset & Course | Sudden (foreign body) vs gradual (infection/asthma) |
| Frequency/Pattern | Recurrent vs first episode |
| Triggers | Viral infection, allergen, exercise, cold air, smoke |
| Associated Symptoms | Fever, cough, coryza, vomiting, feeding difficulty |
| Past Medical History | Previous wheezing, atopy, eczema, prematurity, GERD |
| Family/Social History | Asthma, allergies, smoking, housing |
| Drug history | Recent medications, response to bronchodilators |
4. Physical Examination
- General: Distress, cyanosis, growth, hydration.
- Respiratory system:
- Chest expansion, use of accessory muscles
- Percussion (hyperresonant / dull)
- Auscultation:
- Wheeze: polyphonic (asthma/viral), monophonic (focal obstruction)
- Air entry: symmetrical or reduced
- Crackles: suggest infection or bronchiolitis
- Cardiac: Murmurs (congenital lesions)
- Other systems: Skin (eczema), ENT (allergic rhinitis), clubbing.
5. Differential Diagnosis
| Age Group | Common Causes |
|---|---|
| Infant (<1 yr) | Bronchiolitis, congenital airway anomalies, aspiration, GERD |
| Toddler (1–5 yr) | Viral-induced wheeze, foreign body aspiration, asthma |
| Older child (>5 yr) | Asthma, allergic bronchitis, chronic suppurative lung disease |
6. Investigations
(Usually guided by clinical picture; many cases diagnosed clinically)
- Pulse oximetry – essential.
- Chest X-ray – if first episode, focal findings, suspicion of foreign body/pneumonia.
- Blood tests – if severe or infection suspected.
- Allergy testing / IgE – in recurrent or atopic cases.
- Spirometry / Peak Flow – for older cooperative children (asthma diagnosis).
- Bronchoscopy – if persistent localized wheeze or suspicion of foreign body.
7. Management
A. Immediate Management
- Mild/Moderate:
- Nebulized or inhaled salbutamol (via spacer or nebulizer)
- Oxygen if SpO₂ < 94%
- Oral prednisolone if known asthma or recurrent wheeze
- Severe / Life-threatening:
- High-flow oxygen
- Nebulized salbutamol ± ipratropium bromide
- IV steroids (hydrocortisone)
- IV magnesium sulfate / aminophylline / salbutamol if poor response
- Consider PICU referral
B. Underlying Cause
- Bronchiolitis – supportive (O₂, fluids, suction)
- Foreign body – urgent ENT/pulmonary referral
- Asthma – follow stepwise management (as per BTS/SIGN or GINA)
8. Long-term Management
- Identify triggers and educate parents on avoidance.
- Asthma education: inhaler technique, action plan.
- Follow-up to reassess control and adjust therapy.
9. Red Flags
- Silent chest, exhaustion, cyanosis
- Poor air entry or asymmetry
- Persistent localized wheeze
- Failure to thrive or recurrent pneumonia
- Sudden onset without infection (→ foreign body)
10. Summary Table
| Step | Key Action |
|---|---|
| 1 | ABC and severity assessment |
| 2 | Focused history |
| 3 | Physical examination |
| 4 | Consider differential diagnoses |
| 5 | Targeted investigations |
| 6 | Manage acutely + treat cause |
| 7 | Educate and follow-up |