Normal Lung Sounds

Bronchial

The sound heard over large airways near the second and third intercostal spaces and has a tubular quality that can be compared to air blowing through a cardboard tube. It is relatively louder in expiration than inspiration and are loud and high in pitch.

Vesicular

Vesicular sounds are heard from a distance to the large airways in the lungs. It is comparable to the sound of air blowing to the leaves of the trees and is louder in inspiration than expiration.

Bronchovesicular

Are heard in the center of the anterior chest, are softer than bronchial sounds but are of tubular quality. It is equal during inspiration and expiration. Normal findings on auscultation include:

  • Loud, high-pitched bronchial breath sounds over the trachea
  • Medium pitched bronchovesicular sounds over the mainstream bronchi, between the scapulae, and below the clavicles
  • Soft, breezy, low-pitched vesicular breath sounds over most of the peripheral lung fields.

Abnormal Breath Sounds

Rales

Can be simulated by rolling hair near the ear between two fingers and is best heard on inspiration by the lower bases of the lungs. This is associated with bronchitis, pneumonia, and congestive heart failure and is unrelieved by coughing.

Wheezes

High-pitched and squeaky. Is best heard on expiration on all lung fields and is often associated with bronchitis and pneumonia. It is often unrelieved by cough

Ronchi

Is coarse, harsh, and loud gurgling and is best heard on expiration over bronchi and trachea. Associated with bronchitis and pneumonia and is often relieved by coughing

Stridor

Harsh, high-pitched, audible sound. Is easily heard without a stethoscope during inspiration and expiration and can indicate a progressive narrowing of the upper airway and can be life threatening. It is associated with partial airway obstruction, croup (on inspiration), and epiglottitis (when severe and audible).

Unilaterally Absent or Diminished

No equal or bilateral breath sounds. It is associated with pneumothorax, hemothorax, tension pneumothorax, or pneumectomy.