American EMT Academy Week III Practice Test

Stridor is a high-pitched, harsh sound heard during inspiration when air is trying to move through a narrowed upper airway, such as the larynx or trachea. This indicates swelling or obstruction in the upper airway from causes like infection, allergic reaction, or trauma. It’s a red flag in the field because it points to compromised airway patency and often requires urgent airway assessment and supportive care (oxygen, monitoring, and preparedness for advanced airway if needed). Rales are crackling sounds from fluid in the lungs, heard with the lower airways and alveoli. Rhonchi are coarse, snoring-like sounds from secretions in larger airways. Wheezing is a musical sound from narrowing of smaller airways due to bronchospasm or edema in the bronchial tree. Stridor’s upper-airway origin distinguishes it from these other sounds.