Pulmonary function tests (PFTs) are a group of tests that measure how well your lungs work. This includes how well you’re able to breathe.
Your doctor may order these tests :
- if you’re having symptoms of lung problems
- if you’re regularly exposed to certain substances in the environment or workplace
- to monitor the course of chronic lung disease, such as asthma or chronic obstructive pulmonary disease (COPD)
- to assess how well your lungs are working before you have surgery
- SVC (Slow Vital Capacity) : SVC gives a measure of the change in volume of gas in the lungs from complete inspiration to complete expiration or vice versa. The measurement begins with the subject quietly breathing in a steady-state condition followed by a maximal breath-in and a full breath-out.
- MVV (Maximum Voluntary Ventilation) : The volume of gas that can be breathed in 15 seconds when a person breathes as deeply and quickly as possible. The result is extrapolated from 15 seconds to show what could be achieved over one minute. At the best of times, the MVV can be a difficult test to assess in terms of patient effort and compliance.
- FVC (Forced vital capacity) : The forced vital capacity (FVC) measurement shows the amount of air a person can forcefully and quickly exhale after taking a deep breath. Determining your FVC helps your doctor diagnose a chronic lung disease, monitor the disease over time and understand the severity of the condition.