Physiology 2

Question 1

Major inspiratory muscles

Answer 1

External intercostal muscles

Diaphragm

Question 2

Accessory muscles of inspiration?

Answer 2

Pectoral
Sternocleidomastoic
Scalenus

Question 3

What do accessory muscles of inspiration do?

Answer 3

Contracts only during forceful respiration

Question 4

Muscles of active expiration?

Answer 4

Internal intercostal muscles

Abdominal Muscles

Question 5

What do muscles of active expiration do?

Answer 5

Contracts only in active expiration

Question 6

Total lung capacity?

Answer 6

Over 7L

Question 7

Tidal Volume?

Answer 7

Volume of air entering or leaving lungs during a single breath
TV
0.5L

Question 8

Inspiratory Reserve Volume?

Answer 8

Extra volume of air that can be maximally inspired over and above the typical resting tidal volume
IRV
3.0L

Question 9

Expiratory Reserve volume?

Answer 9

Extra volume of air that can be actively expired by maximal contraction beyond the normal volume of air after a resting tidal volume
ERV
1.0L

Question 10

Residual Volume?

Answer 10

Minimum volume of air remaining in the lungs even after a maximal expiration
RV
1.2L

Question 11

Inspiratory Capacity?

Answer 11

Maximum volume of air that can be inspired at the end of a normal quiet expiration
IC
3.5L

Question 12

Equation for Inspiratory capacity?

Answer 12

IC= IRV + TV

Question 13

Functional Residual Capacity?

Answer 13

Volume of air in lungs at end of normal passive expiration
FRC
2,2L

Question 14

Equation for FRC?

Answer 14

FRC=ERV+RV

Question 15

Vital Capacity?

Answer 15

Maximum volume of air that can be moved out during a single breath following a maximal inspiration
VC
4.5L

Question 16

Vital Capacity Equation?

Answer 16

VC= IRV + TV + ERV

Question 17

Total Lung Capacity?

Answer 17

Total volume of air the lungs can hold
TLC
5.7L

Question 18

Total lung capacity equation?

Answer 18

TLC= VC + RV

Question 19

What can not be measured by spirometry?

Answer 19

Residual Volume - hence not able to measure total lung volume by spirometry

Question 20

When does residual volume increase?

Answer 20

When the elastic recoil of lungs is lost eg emphysema

Question 21

What are dynamic lung volumes useful in?

Answer 21

Diagnosis of obstructive, restrictive lung disease

Question 22

Spirometry results for an airway obstruction?

Answer 22

FVC= low or normal
FEV1=low
FEV1/FVC= low

Question 23

Spirometry Results for a Lung restriction

Answer 23

FVC= Low
FEV1=low
FEV1/FVC=normal

Question 24

Spirometry results for combo of obstructuve and restrictive?

Answer 24

FVC=low
FEV1 =low
FEV1/FVC=low

Question 25

Airway resistance equation?

Answer 25

F= change in P/ r F=Flow P=Pressure R= Resistance

Question 26

Primary determinant of resistance?

Answer 26

Radius of conducting airway

Question 27

Parasympathetic Stimulation causes?

Answer 27

Bronchoconstriction

Question 28

Sympathetic Stimulation causes?

Answer 28

Bronchodilatation

Question 29

What happens during inspiration?

Answer 29

Airways are pulled open by the expanding thorax | Intrapleural pressure falls during inspiration

Question 30

What happens during expiration?

Answer 30

Chest Recoils | Intrapleural pressure rises

Question 31

What helps push air out of the lungs?

Answer 31

Pressure applied to alveolus

Question 32

Dynamic airway compression in normal people?

Answer 32

Causes no problem Increased airway resistance, increases in airway pressure upstream which helps open up the airways by increasing the driving pressure between the alveolus and the airways (the pressure downstream)

Question 33

Dynamic airway compression in people with obstruction?

Answer 33

Causes a problem Driving pressure is lost between alveolus and airway over obstructed segment- causes fall in airway pressure along the airway downstream = airway compression by rising pleural pressure during active expiration

Question 34

When does dynamic compression of airways become worse in patients with an obstruction?

Answer 34

When the patient has decreased elastic recoil of lungs

Question 35

What does a peak flow meter do?

Answer 35

Gives an estimated of peak flow rate

Question 36

When is a peak flow test useful?

Answer 36

With patients who have an obstructive lung disease

Question 37

How is peak flow rate measured?

Answer 37

Patient does short sharp blow into machine, best of 3 attempts is taken

Question 38

What is pulmonary compliance?

Answer 38

A measure of how much effort has to go into stretching or distending the lungs

Question 39

The less compliant the lungs are...

Answer 39

The more work is required to produce a given degree of inflation

Question 40

Pulmonary compliance is decreased by?

Answer 40

``` Pulmonary oedema Pulmonary fibrosis Lung collapse pneumonia Absence of surfactant ```

Question 41

Decreased pulmonary compliance causes?

Answer 41

A greater change in pressure is needed to produce a given change in volume = shortness of breath

Question 42

Increased pulmonary compliance?

Answer 42

May occur if the elastic recoil of lungs is lost | Occurs in emphysema

Question 43

What does compliance increase with?

Answer 43

Increased age

Question 44

Energy required for quiet breathing?

Answer 44

3% of total energy expenditure

Question 45

When is work of breathing increased?

Answer 45

Pulmonary compliance decreases Airway resistance increases Elastic recoil is decreased Need for increased ventilation