Normal Breath Sounds
Clinical Characteristics
- Nonmusical
- Soft
- Heard on inspiration and on early expiration
Clinical Correlations
- Diminished by factors affecting sound generation (e.g., hypoventilation, airway narrowing) or sound transmission
- Assessed as aggregate score with normal breath sound*
- Rules out clinically significant airway obstruction*
Patients should be instructed to breathe deeply in and out through the open mouth.
Misnomer of the term “vesicular”. Note the longer inspiratory phase relative to the expiratory phase during normal breathing. It is a waltz cadence.
Tracheal Breath Sounds
Clinical Characteristics
- Hollow
- Nonmusical
- Heard clearly in both phases of respiratory cycle
Clinical Correlations
- Represents intrapulmonary sounds
- Can be disturbed (e.g., become noisier or even musical) if upper-airway patency is altered
- Indicates upper-airway patency
- Serves as good model of bronchial breathing
Bronchial Breathing
Clinical Characteristics
- Soft
- Nonmusical
- Heard on both phases of respiratory cycle (mimics tracheal sound)
Clinical Correlations
- Indicates patent airway surrounded by consolidated lung tissue (e.g., pneumonia) or fibrosis
Stridor
Clinical Characteristics
- Musical
- High-pitched
- May be heard over upper airways or at a distance without a stethoscope
Clinical Correlations
- Indicates upper-airway obstruction
- Associated with extrathoracic lesions (e.g., laryngomalacia, vocal-cord lesion, postextubation) when heard on inspiration
- Associated with intrathoracic lesions (e.g., tracheomalacia, bronchomalacia, extrinsic compression) when heard on expiration.
Wheezing
Clinical Characteristics
- Musical
- High pitched
- May be heard on inspiration, expiration, or both (However, it is very uncommon to hear inspiratory wheezing in the absence of expiratory wheezing).
Clinical Correlations
- Suggests airway narrowing or blockage (e.g., foreign body, tumor) when localized
- Associated with generalized airway narrowing and airflow limitation when widespread (e.g., in asthma, chronic obstructive pulmonary disease [COPD])
- •Allows determination of extent of airflow limitation; the greater the number of airways generating wheezes, the greater the degree of overall airflow limitation
Rhonchus
Clinical Characteristics
- Musical, similar to snoring
- Lower in pitch than wheeze
- May be heard on inspiration, expiration, or both
Clinical Correlations
- Associated with rupture of fluid films and abnormal airway collapsibility
- Often clears with coughing, suggesting a role for secretions in larger airways
- Is nonspecific
- Often occurs with airway narrowing caused by mucosal thickening or edema or by bronchospasm (e.g., bronchitis, COPD)
Crackles
As a general rule, the higher the pitch of a crackle the more distal it is in origin.
Early inspiratory
- Somewhat coarse
- Not plentiful
- Associated sounds
- Squeaks (Laennec’s “cris d’un petit oiseau”)
- Squawks
- No change with a change in position
- Heard in chronic bronchitis, emphysema, asthma
Late inspiratory
- Fine
- Plentiful
- Diminish or disappear with a change in position of the bases of the lung relative to the heart
- Heard in heart failure, pneumonia, interstitial lung disease, atelectasis, sarcoidosis, others
Fine Crackles
Clinical Characteristics
- Nonmusical
- Short and explosive
- Heard on mid-to-late inspiration and occasionally on expiration
- Unaffected by cough
- Gravity-dependent
- Not transmitted to mouth
Clinical Correlations
- Is unrelated to secretions
- Associated with various diseases (e.g., interstitial lung disease, congestive heart failure, pneumonia
- Can be earliest sign of disease (e.g., idiopathic pulmonary fibrosis, asbestosis)
- May be present before detection of changes on radiography (One cannot see a crackle on a chest x-ray)
If the fine crackles are very plentiful, they are termed “Velcro-type crackles” and usually indicated pulmonary fibrosis of any etiology.
Coarse Crackles
Clinical Characteristics
- Nonmusical
- Short and explosive
- Heard on early inspiration and throughout expiration
- Affected by cough
- Transmitted by mouth
Clinical Correlations
- Indicates intermittent airway opening
- May be related to secretions (e.g., in chronic bronchitis
Velcro-like Crackles (mid-to-late inspiratory crackles)
Special instance of velcro-like crackles
- Very fine
- Quite plentiful
- No change with position
- Heard in pulmonary fibrosis of any etiology
Pleural Friction Rub
Clinical Characteristics
- Nonmusical
- Explosive
- Usually biphasic
- Typically heard over basal regions
Clinical Correlations
- Associated with pleural inflammation or pleural tumors
Inspiratory Squawk
Clinical Characteristics
- Mixed, with short musical component (similar to a short wheeze)
- Accompanied or preceded by crackles
Clinical Correlations
- Associated with conditions affecting distal airways.
- May suggest hypersensitivity pneumonia or other types of interstitial lung disease in patients who are not acutely ill.
•May indicate pneumonia in patients who are acutely ill.
According to Mangione, these are heard in bronchiolitis obliterans, pulmonary fibrosis and allergic alveolitis.
Bronchophony
Bronchophony describes lung sounds heard over an area of consolidation. Normally, spoken words are no well heard when listening to the chest with a stethoscope. However, in the presence of consolidation, these sounds are clearly heard. In this example, the patient is saying “ninety nine”. However, asking the patient to say “boy toy” each and every time the stethoscope is applied to the chest is more effective.
Egophony
Egophony is a form of bronchophony in which the spoken syllables have a nasal or bleating quality. The patient is asked to say the letter e.
In egophony, this will be heard as a nasal letter a (as in the English pronounciation “ah” rather than the American pronounciation “ay”)
Whispering pectoriloquy
Heard in lung consolidation as with bronchophony and egophony. Again, whispered sounds are more clearly heard and louder when auscultated in a patient with lung consolidation. In the above example, the patient is whispering, “one, two, three”. Whispering, “sixty six whiskies please” may be a bit more effective and will bring a smile to your patient’s face.
Amphoric breath sounds
In this example, shortly after inspiration, one hears a hollow sound analogous to a sound generated when one blows across the top of a wide mouthed jar. Amphora is the Latin for jar. During expiration, one hears high pitched crackles and wheezing.
Amphoric breath sounds are produced in the setting of a cavern, hole, cyst, bleb or other air containing structure which is in communication with the bronchial system.
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