Why does bronchiolitis cause wheezing?

Bronchiolitis inflames the bronchioles, which are very small breathing tubes. Their already narrow space can become tighter because of swollen lining and secretions. Air passing through a narrowed tube may become turbulent, producing wheeze that is often more noticeable while breathing out. The sound can vary during the illness as congestion and airway swelling change.

Wheezing is a very common presentation of Bronchiolitis. Wheeze can also occur with other respiratory conditions, so the sound should be considered alongside the child’s age, cough, breathing effort and general condition.

Keep the child away from smoke, vaping aerosols and strong fragrances. Offer fluids or feeds often, because working harder to breathe can make feeding tiring. A blocked nose can worsen feeding difficulty, so saline drops and gentle suction may help before feeds when appropriate.

Use inhalers, nebulisers or other medicines only if they have been prescribed for this child and you have been shown how to use them. Do not use another person’s medicine for a wheezy child.

Get urgent medical help for visible pulling in under the ribs or at the neck, grunting, pauses in breathing, blue or grey lips, severe tiredness, or inability to feed because of breathing difficulty. Seek prompt assessment when wheeze is increasing, the child is drinking much less, or wet nappies are clearly reduced.

Ask the clinician to show you signs of increased work of breathing and explain how to judge whether feeding and hydration are adequate. Ask whether there is a personalised action plan if the child has had wheezing before or has another medical condition.