Abnormal sounds are also called adventitious
breath sounds. Here’s a list of common adventitious breath sounds with explanations and causes. Become familiar with the sounds and how to correctly document them. When possible, seek out learning experiences to hear different breath sounds!
- Wheezing is a continuous high-pitched musical sound on expiration or inspiration. A wheeze is the result of narrowed airways. Common causes include asthma, emphysema, anaphylaxis, a foreign body in the mainstem bronchus, or a fixed lesion such as a tumor.
- Rhonchi are characterized by low pitched sounds heard on inspiration and expiration. Rhonchi are a lower pitched variant of the wheeze. It has a snoring, gurgling or rattle-like quality. Rhonchi, unlike wheezes, may disappear after coughing, which suggests that secretions play a role. Although many clinicians still use the term rhonchi, some prefer to refer to the characteristic musical sounds simply as high-pitched or low-pitched wheezes.
- Crackles or rales may be described as fine (soft, high-pitched) or coarse (louder, low-pitched). The sound of hair being rubbed between one’s fingers is often used as an example to describe these types of sounds. Crackles suggest the presence of intra-alveolar fluid as seen with congestive heart failure, pneumonia, and interstitial lung disease.
- Stridor is a high-pitched musical breath sound resulting from turbulent air flow in the larynx or lower in the bronchial tree. It is often intense and can be heard without a stethoscope. Stridor usually requires immediate intervention.
- Inspiratory stridor suggests obstruction above the vocal cords (i.e., angioedema, epiglottitis, foreign body).
- Expiratory stridor or mixed inspiratory/expiratory stridor suggests obstruction below the vocal cords (i.e., croup, bacterial tracheitis, tumor, foreign body).
- Diminished breath sounds can be caused by anything that prevents air from entering the lungs. Such conditions include atelectasis, severe COPD, severe asthma, pneumothorax, tension pneumothorax, and extrinsic bronchial compression from tumor.
Bickley, L. S., Szilagyi, P. G., Hoffman, R. M., & Soriano, R. P. (2021). Bate’s Guide to Physical Examination and History Taking (13th ed.). Wolters Kluwer Health: Philadelphia.