A. Tidal volume
B. Residual volume
C. Vital capacity
D. Inspiratory reserve capacity
Ans. is ‘B’ i.e., Residual Volume (RV)
This apparatus is Spirometry and it cannot measure Residual Volume (RV)
- Pulmonary ventilation can be studied by recording the volume movement of air into and out of the lungs, a
- method called spirometry.
- Spirogram indicates changes in lung volume under different conditions of breathing.
- It consists of a drum inverted over a chamber of water, with the drum counterbalanced by a weight.
- In the drum is a breathing gas, usually air or oxygen; a tube connects the mouth to the gas chamber.
- When one breathes into and out of the chamber, the drum rises and falls, and an appropriate recording is made on a moving sheet of paper.
Spirometry can measure:-
- Tidal volume (TV)
- Inspiratory reserve volume (IRV)
- Expiratory reserve volume (ERV)
- Vital capacity (VC)
- Forced vital capacity (FVC)/ Forced Expiratory Volume in one second (FEV1)
Spirometry cannot measure:-
- Residual Volume (RV)
- Functional Residual Capacity (FRC)
- Total Lung Capacity (TLC)