Respiration - Mechanics Flashcards

1
Q

What is oxygen pressure in blood at rest?

A

PO2 = 100+/-2 mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is carbon dioxide pressure in blood at rest?

A

PCO2 = 40+/-2 mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the oxygen exchange at rest?

A

250ml/min

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is carbon dioxide exchange at rest?

A

200ml/min

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the oxygen exchange and carbon dioxide exchange when walking 3mph?

A

800ml/min
750ml/min

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the oxygen exchange and carbon dioxide exchange when exercising extremely?

A

5000ml/min
6000ml/min

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the function of the upper airways?

A

conduct air into lungs
humidify air
warm air
filter air

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the lining of the upper airways

A

pseudo-stratified ciliated columnar epithelium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the value of ventilation at rest?

A

6-7 L/min

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How many breathes are taken per min at rest?

A

12-15 breathes of 500ml

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is max value of ventilation?

A

160 L/min

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are max breathes taken per min?

A

40 breathes of 40L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is cardiac output, bpm and blood per beat during rest?

A

5L/min, 70bpm, 70ml/beat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is max cardiac output, bpm and blood per beat?

A

25L/min, 200bpm, 125ml/beat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

In quiet breathing what process is active and what process is passive?

A

inspiration = active
expiration = passive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What happens during inspiration in quiet breathing?

A

diaphragm contracts downwards pushing abdominal contents outwards

external intercostal muscles pull ribs upwards and outwards

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What happens during expiration in quiet breathing?

A

elastic recoil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

In strenuous breathing what process is active and what process is passive?

A

inspiration = active
expiration = active

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What happens during inspiration in strenuous breathing?

A

greater contraction of diaphragm and external intercostal muscles

inspiration accessory muscles are activated (sternocleidomastoid, alae nasi, genioglossus)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What happens during expiration in strenuous breathing?

A

abdominal muscles are engaged (internal and external oblique, rectus abdominus, transverse abdominus)

internal intercostal muscles oppose external intercostal muscles pushing ribs down and inwards

21
Q

What happens to the diaphragm during inspiration?

A

domes flatten as the muscle contracts

22
Q

What are the muscles of inspiration (main + accessory)?

A

main - diaphragm, external intercostals
accessory - sternocleidomastoid, alae nasi, genioglossus

23
Q

What are the muscles of forced expiration?

A

internal intercostal, abdominal muscles, (rectus abdominus, transverse abdominus, external/ internal oblique)

24
Q

What do the internal intercostal and abdominal muscles do?

A

depress ribs

25
Q

What is pleural pressure?

A

pressure surrounding the lung, within the pleural space.

generated by the opposing elastic recoils of the lung and chest wall and the forces generated by respiratory muscles.

26
Q

What is alveolar pressure?

A

pressure inside of the alveoli

27
Q

What is transpulmonary pressure?

A

Transpulmonary pressure is the difference between the alveolar pressure and the intrapleural pressure in the pleural cavity.

28
Q

What is the alveolar pressure at the beginning of inspiration?

A

= barometric

29
Q

What happens to the pleural pressure when muscles contract during inspiration?

A

becomes more negative

30
Q

What happens when the alveolar volumes increases during inspiration to the alveolar pressure?

A

becomes negative

31
Q

What is the barometric/atmospheric pressure?

A

the air pressure outside the body

32
Q

When does inspiration end and therefore flow?

A

when the alveolar pressure and the barometric pressure are equal

33
Q

What happens at the start of expiration?

A

thoracic volume decreases and pleural and transpulmonary values return to pre-inspiration

34
Q

When does air flow out of lungs?

A

when alveolar pressure is higher than barometric

35
Q

Why does air enter and leave the lungs?

A

air travels from high pressure to low pressure

36
Q

Describe volume changes and pressure during inspiration

A
  1. Beginning of inspiration - alveolar P = barometric P
  2. Muscles contract, increasing thoracic volume - pleural P becomes more negative, increase in transpulmonary P
  3. Lungs expand and alveolar volume increases, air enters into alveoli from a high to low concentration - alveolar P becomes negative (less than barometric)
  4. End inspiration, muscles stop contracting thorax stops expanding -alveolar P = barometric P
37
Q

Describe volume changes and pressure during expiration?

A
  1. Beginning of expiration, thoracic volume decreases, pleural P and transpulmonary P return to pre-inspiration values
  2. thorax and lungs recoil, air in alveoli becomes compressed and exits - alveolar P becomes higher than barometric P
38
Q

What’s the difference of depth of diaphragm contraction in relaxed vs strenuous breathing?

A

1cm relaxed
up to 10cm strenuous

39
Q

How much oxygen per litre breathed in healthy relaxed lungs?

A

1ml (2% of resting energy expenditure)

40
Q

What breathing is more efficient and less turbulent?

A

low level breathing (less muscles used)

41
Q

What is the functional residual capacity (FRC)?

A

Volume of air in lungs at the end of expiration during quiet breathing

ERV + residual volume

Outward and inward forces and equal and chest is relaxed

42
Q

Why does the FRC decrease in patients with neuromuscular disorders?

A

chest muscles are weaker therefore lung elastic recoil is greater and forces are unbalanced

43
Q

What is the tidal volume (TV)?

A

volume during relaxed breathing
usually 500ml

44
Q

What is the inspiratory reserve volume (IRV)?

A

forceful inhalation
3300ml

45
Q

What is the expiratory reserve volume (ERV)?

A

forceful exhalation
1000ml

46
Q

What is residual volume?

A

air present we cannot exhale
1200ml

47
Q

What is the vital capacity?

A

the TV + IRV + ERV

48
Q

What is the total lung capaccity in males vs females?

A

males = 6000ml
females = 4200ml

49
Q

What is the FVC?

A

forced vital capacity - similar to VC however it is the maximum air inhaled and exhaled