FRC
Medical abbreviation · Respiratory
| Stands for | Functional residual capacity |
|---|---|
| Categories | Medical |
FRC stands for Functional residual capacity, a respiratory abbreviation.
Volume of air remaining in the lungs at the end of a normal, relaxed exhalation, when the inward pull of the lungs balances the outward spring of the chest wall. It serves as the body's oxygen reserve between breaths.
Example: Morbid obesity reduces FRC, so preoxygenate in a head-up position before induction.
Usage notes
FRC falls when lying flat, under anesthesia and with obesity or pregnancy, which shortens the time before oxygen levels drop during apnea and explains why preoxygenation matters. Positive end-expiratory pressure raises FRC and reopens collapsed alveoli. It rises in obstructive disease because of air trapping.
Related abbreviations
More respiratory abbreviations
- EIB – Exercise-induced bronchoconstriction
- ESS – Epworth Sleepiness Scale
- FeNO – Fractional exhaled nitric oxide
- FEV1 – Forced expiratory volume in 1 second
- FEV1/FVC – Ratio of forced expiratory volume in 1 second to forced vital capacity
- FiO2 – Fraction of inspired oxygen
- FVC – Forced vital capacity
- GGO – Ground-glass opacity
- GINA – Global Initiative for Asthma
- GOLD – Global Initiative for Chronic Obstructive Lung Disease
- HCAP – Healthcare-associated pneumonia
- HFNC – High-flow nasal cannula
See all 109 respiratory abbreviations →
This entry is for general education and is not medical advice. Abbreviation use varies between institutions; always confirm in context.