Lung Tests and Measures

Question 1

What is tidal volume and how can you objectively measure it?

Answer 1

Its the amount of air in a normal breath

You can measure it with a tape measure

Question 2

Whats IRV?

Answer 2

Inspiration Reserve Volume (max amount of air you can take in after you’ve already taken a normal breath)

Question 3

What is ERV?

Answer 3

Expiration Res Volume (max amount of air exhaled after you’ve taken a normal breath)

Question 4

What is RV?

Answer 4

Residual volume (volume of gas that remains in the lungs at the end of ERV)

Question 5

Which patient population may have a higher RV?

Answer 5

COPD patients

Question 6

What is TLC?

Answer 6

Total Lung capacity

IRV+TV+ERV+RV

Question 7

What is VC and how can you measure it?

Answer 7

Vital Capacity
Max amount of air you can force out of the lungs after max inspiration
Measure with a tape measure

Question 8

What is IC?

Answer 8

Inspiration Capacity

max amount of air inspired from resting expiration levels

Question 9

What is FRC?

Answer 9

Functional residual capacity

volume of air remains at rest expir levels (ERV+RV)

Question 10

Give some examples of an obstructive lung disease?

Answer 10

COPD
Bronchitis
Asthma

Question 11

Give some examples of a restrictive lung disease

Answer 11

Cirrhosis
Fibrosis
Poor posture

Question 12

What is a normal value for TV?

Answer 12

400-700 mL

Question 13

What is a normal respiration rate (RR)?

Answer 13

12-20 breaths/min

Question 14

What is a normal Minute ventilation? (TVxRR)

Answer 14

5-10 L/min

Question 15

What can cause a higher min ventilation?

Answer 15

hypoxia, hypercapnia, acidosis, increase dead space vol, anxiety, exercise

Question 16

What can decrease min ventilation?

Answer 16

hypocapnia, alkalemia, resp center depression, neuromuscular disease

Question 17

What is dead space in the lungs/

Answer 17

Volume in lungs that is not perfused with capillary blood flow (125-175 mL)

Question 18

What can increase dead space in the lungs?

Answer 18

PE

pulmonary HTN

Question 19

What is alveolar ventilation?

Answer 19

Volume of air that participates in gas exchange

This is where you get your ABG values

Question 20

What is pulmonary function tests (PFT) important for?

Answer 20

Assists in evaluation of cardiopulmonary status

Assessment of strength and endurance of respiratory mmt

Question 21

What is FVC?

Answer 21

Forced vital capacity (max volume of gas that can be expired forcefully

Question 22

What causes FVC and VC to be smaller than normal?

Answer 22

Restrictive lung disease

Question 23

What is FEV1?

Answer 23

Forced expiratory volume in 1 second

Question 24

Why would FEV1 be smaller in patients with an obstructive disorder?

Answer 24

Decreased elasticity makes it harder for air to expire

Question 25

What are normal FEV1/FVC ratio?

Answer 25

75-85% = normal

Question 26

How can you tell if it's an obstructive or restrictive disorder using FEV1/FVC?

Answer 26

The ratio will be smaller in obstructive patients | In restrictive patients, the ratio will still be in normal limits

Question 27

How can you measure respiratory endurance?

Answer 27

Measure maximum voluntary breaths they can do per min)

Question 28

What are ABG analysis done for?

Answer 28

measure pH ventilation and oxygenation

Question 29

What are the normal ABG values?

Answer 29

PaO2 >80 mm Hg PaCO2 = 35-45 mm Hg pH = 7.35-7.45 HCO3 = 22-26 mEq/L

Question 30

Is respiratory strength measured on inspiration or expiration?

Answer 30

Inspiration