Pulmonary Function Testing

Question 1

Spirometry

Answer 1

● Spirometry is the most common of the Pulmonary Function
Tests and is becoming increasingly available.
● Spirometry measures the volume and
velocity of air that can be inhaled and
exhaled from a patient’s lungs.

Question 2

Pulmonary Function Test results vary by

Answer 2

○ Age
○ Gender
○ Height
○ Weight
○ Race

Question 3

Indications for spirometry

Answer 3

● Detecting pulmonary disease
● Assessing severity or
progression of known disease
● Risk stratification of patients
for certain surgeries

Question 4

Contraindications for spirometry

Answer 4

● Acute disorders affecting test
performance (vomiting, etc)
● Hemoptysis
● Pneumothorax
● Recent cardiothoracic or
abdominal surgery
● Recent eye surgery
● Recent MI or unstable angina
● Known thoracic aneurysm

Question 5

Lung Volumes:

Answer 5

○ Expiratory Reserve Volume (ERV)
○ Inspiratory Reserve Volume (IRV)
○ Residual Volume (RV)
○ Tidal Volume (TV or VT)

Question 6

Lung Capacities:

Answer 6

○ Functional Residual Capacity (FRC)
○ Inspiratory Capacity (IC)
○ Total Lung Capacity (TLC)
○ Vital Capacity (VC)

Question 7

The Tidal Volume is
the ______

Answer 7

total volume of air inhaled or exhaled
during each relaxed respiration cycle.

Question 8

The Inspiratory Reserve Volume is _____

Answer 8

the maximal volume of air inhaled above normal
inspiration.

Question 9

The Inspiratory
Capacity is _____

Answer 9

the maximal volume of air that can be inhaled
above resting exhalation.
○ Tidal Volume + Inspiratory
Reserve Volume

Question 10

The Expiratory Reserve Volume is _____

Answer 10

the maximal volume of air that can be exhaled
below end-respiratory expiration.

Question 11

The Vital Capacity is _____

Answer 11

the largest volume of air measured on
completed exhalation after full inspiration.

Question 12

The Residual Volume is _____

Answer 12

the amount of air remaining in the
lungs after a maximal
exhalation

Question 13

The Functional Residual Capacity is _____

Answer 13

The volume of air in the lungs at resting
end-expiration.

Question 14

The Total Lung Capacity is _____

Answer 14

the amount/volume of air in the lungs at
maximal inspiration.

Question 15

Spirometric Values: most important values

Answer 15

○ Forced Vital Capacity
○ Forced Expiratory Volume
○ Forced Expiratory Flow
○ FEV1/FVC Ratio

Question 16

Forced Vital Capacity (FVC)

Answer 16

The FVC is the total volume of air that can be exhaled during a maximal forced expiratory effort after maximal inhalation.
● FVC is the most important
spirometric value for diagnostic
purposes

Question 17

FEV1/FVC Ratio

Answer 17

● Using the FEV1 and FVC, the FEV1/FVC Ratio is calculated.
● This tells you the percentage of the FVC that the patient can expel in 1 second.
● FEV1/FVC Ratio distinguishes Obstructive
Spirometry patterns from Restrictive Spirometry
patterns.

Question 18

Forced Expiratory Flow (FEF)

Answer 18

Often reported as the FEF25-75%, this represents the average forced expiratory flow rate over the middle 50% of the FVC

Question 19

If the Spirometry suggests an Obstructive ventilatory impairment, perform a _____

Answer 19

Bronchodilator challenge
● Several minutes (10-15) after the bronchodilator treatment, redo the Spirometry testing
○ If there is more than 12% increase in FEV1 and 200 mL increase in FVC, OR a 15-25% increase in FEF25-75%…
■ This suggests a reversible obstructive airway disease, such as asthma or exercise induced bronchospasm.

Question 20

Obstructive pattern of spirometry reveals_____

Answer 20

a decreased FEV1 (usually), normal or decreased FVC, and decreased FEV1/FVC ratio of 0.7 or less

Question 21

Restrictive pattern of
spirometry reveals _____

Answer 21

a normal or decreased FEV1, a decreased
FVC, and a normal or high FEV1/FVC ratio (0.7 or more)