How is wheezing characterized in pediatric asthma?

Updated: Jan 08, 2019
  • Author: Girish D Sharma, MD, FCCP, FAAP; Chief Editor: Kenan Haver, MD  more...
  • Print

A musical, high-pitched, whistling sound produced by airflow turbulence is one of the most common symptoms. The wheezing usually occurs during exhalation.

In the mildest form, wheezing is only end expiratory. As severity increases, the wheeze lasts throughout expiration. In a more severe asthmatic episode, wheezing is also present during inspiration. During the most severe episodes, wheezing may be absent because of the severe limitation of airflow associated with airway narrowing and respiratory muscle fatigue.

Asthma can occur without wheezing when obstruction involves predominantly the small airways. Thus, wheezing is not necessary for the diagnosis of asthma. Furthermore, wheezing can be associated with other causes of airway obstruction, such as cystic fibrosis and heart failure.

Patients with vocal cord dysfunction have a predominantly inspiratory monophonic wheeze/sound (different from the polyphonic wheeze in asthma), which is heard best over the laryngeal area in the neck. Patients with bronchomalacia and tracheomalacia also have a monophonic wheeze.

In exercise-induced or nocturnal asthma, wheezing may be present after exercise or during the night, respectively.

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!