How to Differentiate Between Adventitious Breath Sounds

Pneumonia may cause a discontinuous sound.

When you listen to a person's breathing during auscultation, you may hear a sound that is adventitious, or abnormal. Different types of sounds indicate different breathing problems. You need to understand how to differentiate between these sounds so you can assess the breathing problem correctly.

Instructions

1. Differentiate between the discontinuous sounds: fine crackles and coarse crackles. These sounds are intermittent, and you may hear them if a person has pneumonia due to fluid accumulation.

   Fine crackles are nonmusical, soft, high-pitched, short, cracking and popping sounds heard during inspiration. Coarse crackles are nonmusical, loud, low-pitched, bubbling and gurgling sounds heard during early inspiration and possibly during expiration.

2. Differentiate between the continuous sounds: wheezes and ronchi.

   Wheezing is a musical, high-pitched, squeaky or whistling sound that is heard on expiration and possibly on inspiration. It signals an airway obstruction, such as asthma. Ronchi is musical and low pitched, and sounds like snoring or moaning on auscultation. Ronchi is heard on both inspiration and expiration.

3. Know other sounds, like stridor and pleural friction rub. Stridor, which is often mistaken for a wheeze, is a croaking sound that signals an upper airway obstruction. Pleural friction rub is a rubbing, grating sound caused by inflammation of the lungs.

References

• Loyola University Medical Network: Auscultation of Lungs