What is FVC?
FVC stands for Forced Vital Capacity. It is the amount of air (usually expressed in liters) that a person is able to exhale forcefully and rapidly after a maximal inhalation. It is part of a procedure called “Spirometry” which deals with lung function testing.

To measure Forced Vital Capacity (FVC), a person is asked to pinch his/her nose while breathing through some mouthpiece which is attached to a machine called a spirometer. This spirometer will measure the volume of air that a person is able to inhale or exhale. In typical settings, the person will have to practice the different breathing techniques before the actual measurement. And usually several attempts are recorded for each item of testing, with the highest volume or average volume to be put on record. Sometimes, patients may need to be accustomed to the machine in order to give the best effort, resulting in more reliable results.

The result will be in a form of a graph called a spirogram. This will indicate not only the air volume, but also the rate or speed of air as it travels to and from the lungs. Several other lung capacities can be measured through spirometry. Vital Capacity or VC pertains to the volume of air moving in and out of the lungs with normal inhalation and exhalation. Functional Residual Capacity meanwhile is the measurement of the air left in the lungs after normal breathing. Other items measured during spirometry are Total Lung Capacity (TLC), Inspiratory Capacity (IC), and Forced Expiratory Volume (FEV) among others.

People with bigger lungs and athletes are said to have higher FVC than the average person. Deviation from normal values of Forced Vital Capacity (FVC) and other pulmonary function test items may need immediate care and/or consultation with pulmonary experts, as this may indicate lung problems.