This is the maximum volume that an individual can expire after a single maximal inspiration.
In contrast to the forced maximal capacity the expiration is not performed as quickly as possible but as completely as possible.
The VC is the total lung capacity minus the residual volume.
The VC is reduced in both obstructive and restrictive respirartory disease.
The VC is:
- usually 3-6 litres, varying with age, gender and height
- reduced in obstructive and restrictive defects
- correlated with disability in chronic respiratory disaese