Question

With an obstructive disease, what happens to FEV1(%)? Why do you think this occurs?

Answer 1

In an obstructive lung disease the FEV1 % will DECREASE.

Reason :

FEV1 is the Forced expiratory Volume during the first second . it is the maximum amount of air that a person can expire during the first second of forced expiration.

obstructive lung disease like COPD, asthma , Bronchiectasis arecharacterized by the obstruction in the Respiratory Airway passage.

This obstruction in the respiratory passage will reduces the amount of air exhaled during the first second of forced expiration.

the total amunt of air expired in the forced expiration is called forced vital capacity (FVC)

Severity of Obstructive lung disease can be graded on the basis of FEV1 %. (GOLD staging)

Grade 1 - FEV1% >= 80%

Grade 2 -FEV1 % is 50 - 79%

Grade 3 - FEV1 % is 30 -49%

Grade 4 - FEV1 % is <30%