FEV1
Pronunciation: F-E-V-one
Also written as: FEV1 — Forced Expiratory Volume in 1 second
Forced expiratory volume in 1 second, a key spirometry measurement indicating airway obstruction when reduced in pediatric patients.
Full Definition
FEV1 (forced expiratory volume in 1 second) represents the maximum volume of air that can be exhaled during the first second of a forced expiratory maneuver following a full inspiration. This measurement is fundamental in pediatric pulmonology for diagnosing and monitoring obstructive airway diseases such as asthma and cystic fibrosis. FEV1 values are interpreted relative to predicted normal values based on the child's height, age, sex, and ethnicity. A reduced FEV1, particularly when combined with a low FEV1/FVC ratio, indicates airway obstruction. Serial FEV1 measurements help track disease progression and treatment response over time.
Usage
Usage note: Always expressed as percentage of predicted normal values for accurate interpretation in pediatric patients.
In Context
- "The patient's FEV1 was 75% of predicted with significant improvement following bronchodilator use." — Spirometry interpretation
- "Serial FEV1 measurements showed progressive decline over the past year despite optimal therapy." — Disease monitoring report