 # Spirometry

### SPIROMETRY

Q. 1 Spirometry measures all of the following, except:
 A Tidal volume B Vital capacity C FEV D None of the above
Q. 1 Spirometry measures all of the following, except:
 A Tidal volume B Vital capacity C FEV D None of the above
Ans. D

Explanation:

None of the above

Q. 2

Which of the following is true about Residual volume?

 A Is a part of the expiratory reserve volume B Is a part of vital capacity C Cannot be measured directly with a spirometer D Represents the resting volume of the lungs
Q. 2

Which of the following is true about Residual volume?

 A Is a part of the expiratory reserve volume B Is a part of vital capacity C Cannot be measured directly with a spirometer D Represents the resting volume of the lungs
Ans. C

Explanation:

The volume of air remaining in the lungs after a maximal effort to exhale all the air possible (ie, after your best effort to “empty” your lungs) is the residual volume. This volume cannot be measured directly by a spirometer, which measures only change in volume. Since you cannot voluntarily change your lung volume below the residual volume, the spirometer cannot measure it. Other methods (eg, body plethysmography, inert gas dilution) must be used to measure residual volume.

Q. 3

Which of the following is measured by the device, Bellow’s spirometer?

 A TLC B RV C Closing volume D ERV
Q. 3

Which of the following is measured by the device, Bellow’s spirometer?

 A TLC B RV C Closing volume D ERV
Ans. D

Explanation:

The spirometer is a simple device for measuring gas volumes. The frequently used water spirometer, rolling seal spirometer and bellows spirometer. The last two are not water-filled and are more portable.

The VT, IRV, ERV, IC, and VC can all be measured with a spirometer (as can the forced expiratory volume in 1 second [FEV1], forced vital capacity [FVC], and forced expiratory flow [FEF25–75%]). The RV, the FRC, and the TLC, however, cannot be determined with a spirometer because the subject cannot exhale all the gas in the lungs.

The lung volumes not measurable with spirometry can be determined by the nitrogen-washout technique, by the helium-dilution technique, and by body plethysmography. The FRC is usually determined, and RV (which is equal to FRC minus ERV) and the TLC (which is equal to VC plus RV) are then calculated from volumes obtained by spirometry.

Ref: Levitzky M.G. (2007). Chapter 3. Alveolar Ventilation. In M.G. Levitzky (Ed), Pulmonary Physiology, 7e.

Q. 4

Spirometry measures all of the following, EXCEPT:

 A Tidal volume B Vital capacity C Forced expiratory volume D None of the above
Q. 4

Spirometry measures all of the following, EXCEPT:

 A Tidal volume B Vital capacity C Forced expiratory volume D None of the above
Ans. D

Explanation:

Residual volume (RV) is the one volume that cannot be measured with a spirometer. The RV cannot be measured with the spirometer because this air cannot be expressed from the lungs. It is measured by indirect methods, such as the helium dilution methods, the nitrogen washout methods, or body plethysmography. Since spirometry cannot measure RV, it is not possible to determine functional residual capacity (FRC) and total lung capacity (TLC) from this test.

Spirometry: is the classic pulmonary function test, which measures the volume of air inspired or expired as a function of time. It can monitor quiet breathing and thereby measure tidal volume, and also trace deep inspirations and expirations to give information about vital capacity. Spirometry may also be used to measure forced expiration rates and volumes and to compute FEV1/FVC ratios.
Residual volume (RV) is the one volume that cannot be measured with a spirometer
because this air cannot be expressed from the lungs. Since spirometry cannot measure RV, it is not possible to determine
• Functional Residual Capacity(FRC) = Residual Volume + Expiratory Reserve Volume.and
• Total Lung Capacity = Insp Reserve Volume + Tidal Volume + Exp Reserve Volume + Residual Volume
It is measured by indirect methods, such as the helium dilution methods, the nitrogen washout methods, or body plethysmography.
The measurements taken by the spirometry device are used to generate a pneumotachograph that can help to assess lung conditions (obstructive or restrictive).

Ref: Essential medical physiology, edited by Leonard R. Johnson, John H. Byrne, 3rd Edition, Page 266.

Q. 5

Spirometry measures all of the following except:

 A TLC B ERV C IRV D FVC
Q. 5

Spirometry measures all of the following except:

 A TLC B ERV C IRV D FVC
Ans. A

Explanation:

Ans:A.)TLC

Spirometry can measure :- Tidal volume (TV), inspiratory reserve volume (IRV), expiratory reserve volume (ERV), vital capacity (VC), forced vital capacity (FVC), FEVI.

Spirometry cannot measure :- Residual volume (RV), functional residual capacity (FRC), total lung capacity (TLC).

Q. 6

Spirometry can demonstrate and measure all of the following except :

 A Tidal volume B Residual volume C Vital capacity D Inspiratory reserve capacity
Q. 6

Spirometry can demonstrate and measure all of the following except :

 A Tidal volume B Residual volume C Vital capacity D Inspiratory reserve capacity
Ans. B

Explanation:

B i.e. Residual Volume

Q. 7

Routine spirometry can’t estimate :

 A FRC B VC C FEV D ERV
Q. 7

Routine spirometry can’t estimate :

 A FRC B VC C FEV D ERV
Ans. A

Explanation:

A i.e. FRC

Q. 8

 A Flow rates can be calculated B Gives false high values at low flow rates C Gives false low values at high flow rates D All
Q. 8

 A Flow rates can be calculated B Gives false high values at low flow rates C Gives false low values at high flow rates D All
Ans. A

Explanation:

A i.e. Flow rates can be calculated

Q. 9

Spirometry cannot measure â€‘

 A RV B TV C IRV D ERV
Q. 9

Spirometry cannot measure â€‘

 A RV B TV C IRV D ERV
Ans. A

Explanation:

Ans. is ‘a’ i.e., RV

Spirometry can measure :- Tidal volume (TV), inspiratory reserve volume (IRV), expiratory reserve volume (ERV), vital capacity (VC), forced vital capacity (FVC), FEVI.

Spirometry cannot measure :- Residual volume (RV), functional residual capacity (FRC), total lung capacity (TLC).