| Quality |
|
| Normal breath sounds (vesicular sounds) |
Inspiratory phase longer than expiratory phase, without interposed gap. Due to transmitted air turbulence. |
| Bronchial breathing |
Harsher noises; prolonged during expiration. Heard over areas of consolidation, where sound is not filtered by alveoli. |
| Amphoric breath sounds (less common) |
Hollow noises, heard over a large cavity. The sound is said to be like the noise of air passing over the top of a hollow jar. |
| Intensity |
|
| Reduced intensity (decreased air entry) |
Muffled breath sounds as a result of pleural effusion, pneumonia, chronic obstructive pulmonary disease collapse, pneumothorax or a mass. |
| Added sounds |
|
| Wheeze (polyphonic) |
Continuous sounds with a musical quality. Note when in the respiratory cycle the wheeze occurs; usually louder in expiration. Due to airway narrowing in asthma or chronic obstructive respiratory disease. |
| Wheeze (monophonic) |
Single note, due to fixed obstruction such as a space occupying lesion. |
| Stridor |
Unlike wheeze, stridor is inspiratory; due to upper airway obstruction |
| Crackles |
Interrupted, non-musical sounds, often occurring due to opening of small airways. Early inspiratory crackles suggest chronic obstructive respiratory disease; whilst later or pan-inspiratory crackles suggest that the disease is limited to the alveoli.Fine crackles sound like Velcro being pulled apart, they are characteristic of pulmonary fibrosis; medium crackles are typical of left ventricular failure whilst coarse crackles indicate pools of retained secretions in conditions such as bronchiectasis. |
| Pleural rub |
A continuous grating sound which occurs with pleurisy as the inflamed pleura rub against each other (e.g. secondary to a pulmonary infarct or pneumonia) |
