Where do wheezes originate in the respiratory cycle?

Where do wheezes originate in the respiratory cycle?

• A. Beginning of inspiration
• B. End of inspiration
• C. Beginning of exhalation
• D. End of exhalation

Answer: (D)

Wheezes come from turbulent airflow through narrowed airways, and this narrowing is most pronounced during expiration. As air is forced out, intrathoracic pressure rises and small airways can undergo dynamic compression, especially when bronchomotor tone, edema, or secretions are present. This creates rapid, oscillating flow through the constricted passages, producing a musical wheeze. The sound is typically most noticeable late in the expiratory phase—near the end of exhalation—when airflow is still present but the small airways remain narrowed. If a wheeze is heard during inspiration, that points more toward upper airway obstruction. So wheezes originate at the end of exhalation.

Wheezes come from turbulent airflow through narrowed airways, and this narrowing is most pronounced during expiration. As air is forced out, intrathoracic pressure rises and small airways can undergo dynamic compression, especially when bronchomotor tone, edema, or secretions are present. This creates rapid, oscillating flow through the constricted passages, producing a musical wheeze. The sound is typically most noticeable late in the expiratory phase—near the end of exhalation—when airflow is still present but the small airways remain narrowed. If a wheeze is heard during inspiration, that points more toward upper airway obstruction. So wheezes originate at the end of exhalation.