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What can doctors learn by listening to breath sounds with a stethoscope?
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respiratory disease
The bronchioles of the lungs are the site where oxygen is exchanged for carbon dioxide during the process of respiration. Inflammation, infection, or obstruction of the bronchioles is often associated with acute or chronic respiratory disease, including bronchiectasis, pneumonia, and lung abscesses.
Doctors use auscultation with a stethoscope to evaluate the sounds of air moving through the lungs, which helps identify various respiratory conditions. By listening to these sounds, physicians can detect obstructions or inflammation associated with diseases such as asthma, bronchitis, or pneumonia.1
Beyond normal breathing sounds, doctors listen for "adventitious" sounds that indicate underlying issues:
- Crackles (or rales): These resemble the sound of hair being rubbed together and are caused by fluid in the small airways. They are often heard in cases of pneumonia or congestive heart failure.1
- Wheezes: These musical sounds typically occur during expiration and indicate rapid airflow through a partially obstructed airway, common in asthma or bronchitis.1
- Pleural rubs: These sound like creaking leather and occur when inflamed pleural surfaces rub against each other, which can be a sign of pneumonia or pulmonary infarction.1