Which sound is most associated with upper airway obstruction?

Stridor is a high-pitched, wheezing sound caused by disrupted airflow in the upper airway, often occurring during inhalation. It is specifically associated with conditions that lead to partial obstruction in the airway above the vocal cords, such as swelling from anaphylaxis, croup, or foreign body aspiration. The presence of stridor indicates that there is a narrowing in the upper airway, making it a clear indicator of upper airway obstruction. This sound is crucial for recognizing the urgency of the situation, as upper airway obstructions can rapidly become life-threatening.

In contrast, wheezing signifies lower airway conditions such as bronchospasm or obstruction within the bronchi, and rhonchi are often related to secretions in the larger airways, which create a rattling sound typically associated with bronchitis or pneumonia. A friction rub is associated with the movement of inflamed pleura and indicates a different clinical condition entirely, usually linked with pleuritis or pericarditis, rather than an obstruction of the airway. Understanding these differences in respiratory sounds helps healthcare providers assess and manage airway conditions effectively.