The physiological consequences of lung disease

Question 1

Minute ventilation =

Answer 1

tidal volume x respiratory rate

Question 2

Alveolar ventilation

Answer 2

(tidal volume - dead space) x respiratory rate

Question 3

What is dead space?

Answer 3

Volume of air inspired that doesn’t take part in gas exchange

Question 4

Muscles of inspiration

Answer 4

Diaphragm
External intercostals
Sternocleidomastoid
Pec minor

Question 5

Expiration is usually a

Answer 5

Passive process

Question 6

Muscles of expiration are activated with

Answer 6

Increased respiratory drive

Question 7

Muscles of expiration

Answer 7

Internal intercostals
Rectus abdominis
Transversus abdominis

Question 8

What is ventilation a balancing act between

Answer 8

Ventilatory capacity

Ventilatory demand

Question 9

Ventilatory capacity =

Answer 9

Maximum spontaneous ventilation that can be maintained without the development of respiratory muscle fatigue

Question 10

Ventilatory demand =

Answer 10

spontaneous minute ventilation required to maintain normal pCO2

Question 11

Name a law of diffusion

Answer 11

Fick’s law of diffusion

Question 12

Fick’s law of diffusion =

Answer 12

Rate of transfer of a gas through a sheet of tissue is proportional to:
1. Tissue area
2. Difference in gas partial pressure
And inversely proportional to:
1. Tissue thickness

Question 13

Normally, perfusion is matched to

Answer 13

Ventilation

Question 14

Name a mechanism that matches ventilation to perfusion

Answer 14

Hypoxic pulmonary vasconstriction

Question 15

What happens when there’s normal ventilation but reduced perfusion =

Answer 15

Alveolar ventilation

Question 16

What happens when theres reduces ventilation but normal perfusion

Answer 16

Shunting of deoxygenated blood

Question 17

Way to measure ventilation =

Answer 17

Helium dilution method using a spirometer

Question 18

Way to measure diffusion =

Answer 18

TLCO/DLCO

Question 19

TLCO

Answer 19

Transfer factor of lung for carbon monoxide

Question 20

DLCO

Answer 20

Diffusion capactiy of carbon monoxide

Question 21

How long does patient hold breath for during a TLCO test?

Answer 21

10 seconds

Question 22

Way to measure perfusion =

Answer 22

CT pulmonary angiogram

ECG

Question 23

Ex of what would reduce perfusion

Answer 23

Pulmonary embolism
Arteriovenous malformations
Intracardiac shunts

Question 24

Normal O2 sat

Answer 24

95-100

Question 25

O2 for COPD

Answer 25

88-92

Question 26

What does a shift of the Hb-O2 dissociation curve to the right mean?

Answer 26

Lower affinity for O2

Question 27

Conditions that shift dissociation curve to right:

Answer 27

``` High H+ Low pH High CO2 High BCG High temp ```

Question 28

What does a shift of the Hb-O2 dissociation curve to the left mean

Answer 28

Higher affinity for O2

Question 29

Conditions that shift dissociation curve to the left

Answer 29

``` Low H+ High pH Low CO2 Low BCG Low temp ```

Question 30

Systems that regulate acid-base balance:

Answer 30

Chemical Respiratory Renal

Question 31

Chemical buffers:

Answer 31

HCO3- PO4- Proteins

Question 32

Respiratory buffers

Answer 32

HCO3-

Question 33

Renal buffers

Answer 33

HCO3- PO4- NH3-

Question 34

Acidaemia =

Answer 34

pH <7.35

Question 35

Alkalaemia

Answer 35

pH >7.45

Question 36

Type 1 respiratory failure =

Answer 36

Low pa(O2), low/normal p(CO2)

Question 37

Types 2 respiratory failure =

Answer 37

``` Low p(O2) High p(CO2) ```

Question 38

In restrictive lung disease air is doing what normally?

Answer 38

Flowing

Question 39

Ex of obstructive lung disease =

Answer 39

Asthma COPD Bronchiectasis

Question 40

Ex of respiratory disease =

Answer 40

Pulmonary fibrosis Obesity Chest wall deformities Neuromuscular disorders

Question 41

What happens to lungs in fibrosis?

Answer 41

Small lungs with reduced compliance