Reduced FEV₁:FVC Ratio
March 4th, 2023
Overview
The ratio between the forced expiratory volume in 1 second (FEV₁) and forced vital capacity (FVC) is also known as the Tiffeneau-Pinelli index. This ratio is used to assess for the fraction of air that the patient is able to expel in the first second, and a reduced ratio is a sign of obstruction.
Normal Range
- >0.70
A reduced FEV₁/FVC ratio (<0.7) is indicative of obstructive pulmonary disease.
Causes of Obstructive Disease
- COPD
- Asthma
- Bronchiectasis
- Cystic fibrosis
- Bronchiolitis
- α1-antitripsin deficiency
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