In an emphysematous patient with bullous leison which is the best investigation to measure lung volumes?
Body plethysmography
Helium dilution
Trans diaphragmatic pressure
DLco
RV ,FRC,TLC cannot measured by spirometry. This are measured by using the helium dilution technique/ body plethysmographY. In patients with severe COPD,and with large bullae in paicular,body plethysmography is preferred because the use of helium may underestimate lung volumes. Reference:Davidson's Medicine -22nd edition,page no:675
Respiratory system