Is wheezing a reliable sign of severe lower airway disease?
No. Audible wheezing requires significant airflow through narrowed small airways. Children with severe obstruction of small airways may have so little airflow that audible wheezing is not present. These children usually have decreased inspiratory breath sounds and increased work of breathing. Administration of bronchodilators to these patients will often increase wheezing because there is more turbulent airflow as the narrowed airways open up.
