Abnormal Breath Sounds

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Abnormal Breath Sounds

There are several abnormal sounds that can be heard over the lung fields.  Click on the stethoscope to hear the abnormal lung sound.  Click on the name of the abnormal lung sound to learn more about the sound.

Row 1-Left=Wheezes (sibilant)
Row 1-Right=Stridor
Row 2-Left=Wheezes (sonorous)
Row 2-Right=Fine Crackles
Row 3-Left=Coarse Crackles
Row 3-Right=Bronchovesicular Breath Sound
Row 4-Right=Bronchial Breath Sound

Wheezes (Sibilant)-a high-pitched, musical sound similar to a squeak.  It is heard most commonly during expiration, but also can be heard during inspiration.  It is heard in narrowed airway diseases such as asthma and chronic emphysema.  

Stridor-a high pitched, piercing sound that occurs secondary to an upper airway obstruction (such as in trachea or larynx) such as croup, foreign body obstruction, large airway tumor.

Wheezes (Sonorous)-(formerly called rhonchi).  Low-pitched, coarse, loud, low snoring or moaning sound.  Heard primarily during expiration, but may also be heard during inspiration.  The mechanism that causes sonorous wheezes is that there is a narrowing of the large airways or an obstruction of the bronchus.  

Fine Crackles-(formerly called rales). High-pitched, short, crackling, popping sounds heard during the end of inspiration and not cleared by coughing.  The mechanism behind these sounds is that inhaled air collides with previously deflated airways and the airways suddenly pop open, creating a crackling sound as gas pressure between the two compartments equalizes.

Coarse Crackles-a loud, low pitched, bubbling or gurgling sound that starts in early inspiration and may extend into the first part of expiration.  They sound like the opening of a Velcro fastener. Coarse crackles may decrease somewhat by coughing or suctioning but will reappear.  The inhaled air collides with secretions in the trachea and large bronchi.  These sounds occur in such conditions as pulmonary edema, pneumonia, pulmonary fibrosis, and terminally ill with a depressed cough reflex.

Bronchovesicular Breath Sound-a moderate pitch, medium intensity breath sound with inspiration equal to expiration (I=E) (1:1).  This breath sound is normally heard at the 1st-2nd ICS at the sternal border (anterior), at T4 medial to scapula (posterior).  This breath sound is abnormal if heard over the peripheral lung fields.  

Bronchial Breath Sound-a harsh, high pitch, low intensity breath sound with expiration longer than inspiration (I<E) (1:2).  This sound is normal over the trachea but always considered abnormal if heard over the peripheral lung fields.  If heard, there is evidence of consolidation of the lungs, as may be seen in patients with pneumonia.