Spirometry

Question 1

What is inspiratory reserve volume (IRV)?

Answer 1

The amount of air in excess tidal inspiration that can be inhaled with maximum effort.

Question 2

What is expiratory reserve volume (ERV)?

Answer 2

The amount of air in excess tidal expiration that can be exhaled with maximum effort.

Question 3

What is vital capacity?

Answer 3

The amount of air that can be exhaled with maximum effort AFTER maximum inspiration.

Question 4

What is vital capacity used to assess for?

Answer 4

Used to assess strength of thoracic muscles as well as pulmonary function.

Question 5

What is tidal volume?

Answer 5

The amount of air inhaled or exhaled in one breath. (500ml per breath)

Question 6

How do you calculate vital capacity?

Answer 6

ERV + TV + IRV

Question 7

What is residual volume?

Answer 7

The amount of air remaining in the lungs after maximum expiration.

Question 8

What is functional residual capacity?

Answer 8

Amount of air remaining in lungs after a normal tidal expiration.

RV + ERV

Question 9

What is inspiration capacity?

Answer 9

Maximum amount of air that can be inhaled after a normal tidal expiration.

TV + IRV

Question 10

Which term is used to describe the maximum amount of air the lungs can contain?

Answer 10

Total lung capacity.

RV + VC

Question 11

What is FEV1?

Answer 11

The forced expiratory volume in 1 second.

Compare result to a predicted value and calculate the percentage of predicted value. 80% and above is healthy.

Good overall assessment of lung health. Reproducible.

Question 12

Describe the steps to obtaining the FVC (forced vital capacity).

Answer 12

1. Breath into total lung capacity
2. Exhale as fast as possible in one second
3. The volume produced is the forced vital capacity for 1 second
4. Compare this result to a predicted value and calculate the percentage of predicted value

Healthy individuals can expire 80% of their vital capacity in 1 second. Low value indicates airway restriction.

Question 13

What is PEF?

Answer 13

Peak expiratory flow rate

Question 14

What can the FEV1/FVC ratio determine?

Answer 14

If there is an abnormal ratio <0.7, then there is airway obstruction.

High ratio + low FVC = airway restriction

Question 15

Describe spirometry results and symptoms for asthma.

Answer 15

FEV1 = normal or reduced
FVC = normal 
PEF = varies

Typified by airway obstruction

Symptoms: variable wheeze + shortness of breath

Question 16

Describe spirometry results and symptoms for COPD.

Answer 16

FEV1 = reduced significantly 
FVC = normal or reduced 
PEF = not variable 

Typified by airway obstruction and intermittent exacerbations.

Symptoms: wheeze + shortness of breath

Question 17

Describe spirometry results and symptoms for pulmonary fibrosis.

Answer 17

FEV1 = reduced significantly 
FVC = reduced significantly 
PEF = not variable 

Symptoms: short breath + persistent dry cough

Question 18

What is the effect of an ageing lung on FEV1 and FVC?

Answer 18

FEV1 and FVC decreases. Spirometry reading may indicate obstruction or disease but may not be the case.

Question 19

What is the tidal volume for the average person?

Answer 19

0.5 L