incentive spirometry

How it is done
http://www.youtube.com/watch?v=LDgvhZjz0g8&feature=related

Deep breathing helps alveoli, the small air sacs deep in your lungs, fully expand. When you lie in bed for a long time (while recovering from injuries or surgeries, for instance) you tend to take shallow breaths and not cough as often as needed. You might start taking shallow breaths in an attempt to decrease pain associated with chest surgery or abdominal surgery.

Using an incentive spirometer will help you return to normal breathing rhythms. By inhaling deeply, you also help mobilize secretions and open areas of the lungs that my have collapsed.Using an incentive spirometer will mimic natural sighing and yawning and encourage you to take slow, deep breaths. Not only will this help restore your regular breathing rhythm, but it will also help you avoid atlectasis (a collapsed or airless condition of the lung) and pneumonia.