Lung Volumes and Capacities

Question 1

What is tidal volume? (definition + volume)

Answer 1

Volume inspired or expired with each normal breath

500mL

Question 2

What is Inspiratory reserve volume? (definition + volume)

Answer 2

• Max volume that can be inspired (on top of tidal volume/normal breath)
• Used during exercise/exertion

2-3L

Question 3

What is Expiratory reserve volume? (definition + volume)

Answer 3

Maximal volume that can be expired after the expiration of a tidal volume/normal breath

1L

Question 4

What is residual volume? (definition + volume)

Answer 4

• Volume that remains in the lungs after a maximal expiration
• CANNOT be measured by spirometry

1L

Question 5

What is Inspiratory capacity (definition + equation + volume)

Answer 5

• Volume of maximal inspiration
• IRV + TV

2.5-4L

Question 6

What is Functional residual capacity (definition + equation + volume)

Answer 6

• Volume of gas remaining in lung after normal expiration
• cannot be measured by spirometry because it includes residual volume:
• ERV + RV

2L

Question 7

What is Vital capacity (definition + equation + volume)

Answer 7

• Volume of maximal inspiration and expiration:
• IRV + TV + ERV = IC + ERV

3-4.5L

Question 8

What is Total Lung capacity (definition + equation + volume)

Answer 8

• Volume of the lung after maximal inspiration
• The sum of all four lung volumes
- IRV+ TV + ERV + RV = IC + FRC
• cannot be measured by spirometry because it includes residual volume

4-6L

Question 9

What is dead space? What two components make up dead space?

What is it’s volume?

Answer 9

Volume of respiratory apparatus that does not participate in gas exchange

• ANATOMIC DEAD SPACE (150mL): volume of the conducting airways (ie. nose, trachea, etc.)
• PHYSIOLOGIC DEAD SPACE (150mL normal lungs, greater if have lung disease) - volume of the lung that does not participate in gas exchange
• 300mL in normal lungs

Question 10

What is forced expiratory volume?

Answer 10

Volume of air that can me expired in1 second after a maximal inspiration

Question 11

What is forced expiratory volume in Normal lungs

Answer 11

80% (0.8) of the forced vital capacity, expressed as FEV1/FVC

Question 12

How does forced expiratory volume change in restrictive and obstructive lung disease

Answer 12

restrictive lung disease: Decreased FEV1 & decreased FVC = ratio ≥ 0.8

obstructive lung disease: Very decreased FEV1 & decreased FVC = ratio < 0.8

Question 13

Stage 0 respiratory condition - Description and Findings

Answer 13

At risk

Risk factors and chronic symptoms but normal spirometry

Question 14

Stage 1 respiratory condition - Description and Findings

Answer 14

Mild

FEV1/FVC ration less than 70%
FEV1 at least 80% of predicted value
May have symptoms

Question 15

Stage 2 respiratory condition - Description and Findings

Answer 15

moderate

FEV1/FVC < 70%
FEV1 50-80% of predicted value
May have chronic symptoms

Question 16

Stage 3 respiratory condition - Description and Findings

Answer 16

Severe

FEV1/FVC <70%
FEV1 30-50% of predicted value
May have chronic symptoms

Question 17

Stage 4 respiratory condition - Description and Findings

Answer 17

Very severe

FEV1/FVC <70%
FEV1 <30% of predicted value
OR
FEV1 < 50% predicted value plus chronic symptoms

Question 18

Summary of S&S of cardiopulmonary disease

Answer 18

• pain in chest, neck, jaw, arms
• SOB at rest or mild exertion
• dizzy or syncope
• orthopnea (SOB while lying flat) or nocturnal dyspnea
• ankle edema
• palpitations or tachycardia
• intermittent claudication
• known heart murmur
• unusual fatigue

Question 19

What is cardiothracic index

Answer 19

Size of heart in relation to thorax