Which sound indicates swelling of the upper airway?

• A. Wheezing
• B. Rales
• C. Rhonchi
• D. Stridor

Answer: (D)

Stridor is the sound that signals swelling in the upper airway. It’s a high-pitched, often harsh, noise typically heard during inhalation because a narrowed upper airway at the larynx or above creates turbulent airflow. This type of sound points to obstruction from swelling, as seen with conditions like croup or epiglottitis, and it can be a medical emergency requiring prompt assessment.

Wheezing, in contrast, comes from narrowing of the smaller airways in the lungs (bronchioles) and sounds like a musical whistle, often heard during expiration. Rales (crackles) result from fluid in the lungs or airways, presenting as crackling sounds. Rhonchi are coarse, snoring noises from secretions in larger airways.