Atelectasis: Assessment

Atelectasis: In this condition, an area of the lung or an entire lung collapses. Atelectasis may be due to airway obstruction, or compression of the lung.  In the diagram above, an obstruction blocks the airway, causing the associated  alveoli to collapse and that area of the lung to shrink.  Any alveolar air beyond the obstruction becomes absorbed by the pulmonary capillaries, and the alveolar walls cave in.

Assessment findings include:


  • cough
  • delayed chest expansion on the affected side
  • increased respiratory rate
  • increased pulse 
  • possible cyanosis


  • chest expansion decreased on the affected side
  • tactile fremitus decreased or absent over the involved area
  • with a large collapse, the trachea may deviate or shift toward the affected side.


  • dull over affected area


  • breath sounds decreased or absent over involved area
  • no adventitious sounds if bronchus is obstructed
  • occasional fine crackles if bronchus is patent

To see a slide of severe atelectasis click on this URL