What term describes the high-pitched whistling sound heard during expiration?

Wheezing is the term used to describe the high-pitched whistling sound that occurs during expiration, often associated with narrowing of the airways. This sound can be a result of conditions such as asthma, chronic obstructive pulmonary disease (COPD), or bronchitis, where inflammation or constriction of the airways leads to turbulent airflow. Wheezing indicates that there is some obstruction present in the lower airways, which affects the normal flow of air and produces that characteristic whistling sound.

In contrast, stridor refers to a high-pitched sound typically heard during inspiration and is often indicative of an upper airway obstruction. Rales and crackles both describe similar sounds commonly associated with fluid in the lungs, heard during inhalation and characterized by a bubbling or popping noise as alveoli open. These distinctions are important in assessing a patient's respiratory status and can guide effective interventions.