Flow Volume Loop

  • Configuration of expiratory limb: Exponential drop in rate of flow
  • Inspiratory limb: Flow rates remain same with a sudden drop off.
  • Peak Expiratory flow
  • Peak Inspiratory flow
  • Patterns

 

 

 

 

 

 

 

 

 

  • FEV1Forced expiratory volume in one second
  • FEF25-75 Maximal mid expiratory flow rate
  • FET Time in seconds to complete FVC
  • Patterns

 

 

 

 

 

 

 

 

TV
IC
ERV
SVC

 

 

 

 

 

 

 

 

 

Maximal Voluntary Ventilation

Note:
Rate
Volume

 

 

 

 

 

 

 

 

 

 

Note:
  • Duration of breath hold
  • Volume of inspiration
  • Start of expiration

 

 

 

 

 

 

 

 

 

 

Lung Compartements

Compare predicted with observed
TLC
RV/TLC