In COPD which is true
COPD is characterised by reduced FEV1 with a reduction in FEV1/FVC ratio less than 0.7.With worsening disease severity,lung volumes may increase,resulting in an increase in TLC,RV and FRC. Reference:Harrison's medicine-18th edition,page no:2156.
FEV1/FVC <0.7
FEV1/FVC (upward arrow)
RV (downward arrow)
TLV (downward arrow)
Respiratory system