Which type of sound indicates an obstruction in the upper airway?

Stridor is a high-pitched, wheezing sound that indicates a narrowing or obstruction of the upper airway, typically occurring in the larynx or trachea. This sound is often heard during inspiration and signifies that air is having difficulty passing through the obstructed area. It is commonly associated with conditions such as croup, epiglottitis, or foreign body aspiration.

Other sounds refer to different types of respiratory conditions and do not specifically indicate an upper airway obstruction. Wheezing is a musical sound resulting from narrowed airways in the lower respiratory tract, commonly seen in asthma or bronchospasm. Rales, or crackles, are sounds caused by fluid in the alveoli or the small airways, often heard in conditions like pneumonia or heart failure. Ronchi are low-pitched, rattling sounds associated with airway obstruction from mucus or secretions in the larger airways. Each of these sounds can denote different pathologies, but stridor specifically points to issues in the upper airway.