Physiology 1 & 2 Flashcards

1
Q

Internal respiration?

A

Intracellular mechanisms that produce O2 and use CO2

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

External respiration?

A

Sequence of events that lead to the exchange of O2 and CO2 between the external environment and the cells of the body

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

4 steps of external respiration?

A

Ventilation (mechanical process of moving air into and out of the lungs)Gas exchange between the alveoli and bloodGas transport in blood (between lungs and tissue)Gas exchange at tissue level

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

Boyle’s law

A

At any constant temperature, the pressure exerted by a gas varies inversely with the volume of the gas

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

Why does air move into the lungs during inspiration?

A

During inspiration, the inspiratory muscles contract causing the thorax and lungs to expand. This causes the intra-alveolar pressure to become less than the atmospheric pressure due to Boyle’s law causing air to flow down the concentration gradient into the lungs

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

What holds the thoracic wall and lungs in close proximity? (2)

A

Intrapleural fluid cohesivenessNegative intrapleural pressure

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

What is the intracellular fluid cohesiveness?

A

Water molecules in intrapleural fluid are attracted to each other and resist being pulled apart causing the plural membranes to stick together

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

Negative intrapleural pressure?

A

The intracellular pressure is below atmospheric pressure which creates a transmural pressure gradient forcing the lungs outwards and chest inwards

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

Atmospheric pressure value?

A

760mmHg

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

Intralveolar pressure value?

A

760mmHg

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

Intrapleural pressure value?

A

756mmHg

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

Is inspiration an active or passive process?Expiration?

A

ActivePassive

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

Major inspiratory muscle?

A

Diaphragm

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

Inspiratory muscles?

A

Diaphragm and external intercostal muscles

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

what gives motor innervation to the diaphragm?

A

Phrenic nerves formed from C3, 4, 5 nerve roots

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

When does air stop entering the lungs?

A

When intra-alveolar pressure equals atmospheric pressure

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

How does expiration occur?

A

Relaxation of the inspiratory muscles causes the chest wall and lungs to recoil to their perspiratory size due to their elastic propertiesThis causes the intra-alveolar pressure to rise due to boyle’s law forcing air out of the lungs down the pressure gradient until intra-alveolar pressure = atmospheric pressure

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

Pneumothorax definiton

A

Air in the pleural space (causes the lung to collapse)

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

Types of pneumothorax?

A

Traumatic (hole in chest wall)Spontaneous (hole in lung wall)

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

What causes a lung to recoil during expiration?

A

Elastic connective tissueAlveolar surface tension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Alveolar surface tension?

A

Attraction between water molecules at liquid air interface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What reduces the alveolar surface tension?

A

Surfactant (lowers surface tension of smaller alveoli more than larger alveoli)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

La Place’s law?

A

P=2T /r (the smaller alveoli have a higher tendency to collapse)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is surfactant made of?

A

Lipids and proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is surfactant secreted by?

A

Type II alveolar cells

26
Q

Respiratory distress syndrome of the newborn?

A

Developing metal lungs are unable to synthesise surfactant until later in the pregnancy meaning premature babies may not have enough surfactant

27
Q

What helps to keep the alveoli open?

A

SurfactantAlveolar interdependancetransmural pressure gradient

28
Q

What is alveolar interdependence?

A

If an alveolus starts to collapse the surrounding alveoli are stretched and then recoil exerting expanding forces in the collapsing alveolus

29
Q

When does respiration become active (2)?

A

Due to exercise or disease

30
Q

Accessory muscles of inspiration? (2)

A

SternocleidomastoidScalenus

31
Q

What instrument is used to measure the air capacity of the lungs?

A

Spirometer

32
Q

Tidal volume?Value for a normal healthy adult male

A

Normal volume of air displaced between normal exhalation and inhalation when extra effort is not applied 500ml

33
Q

Residual volumeValue

A

Amount of air left in the lungs after a forced exhalation1200ml

34
Q

Functional residual capacityValue

A

Volume air left in the lungs at the end of passive expiration 2200ml

35
Q

Vital capacityValue

A

Maximum amount of air a person can expel from the lungs after a maximum inhalation4500ml

36
Q

Total lung capacityValue

A

Most air you can inspire into your lungs5700ml

37
Q

Inspiratory reserve volume Value

A

Additional air that can be forcefully inhaled after the inspiration of a normal tidal volume3000ml

38
Q

Inspiratory capacityValue

A

volume of air that can be inspired after a normal expiration 3500ml

39
Q

Expiratory reserve volumeValue

A

additional air that can be forcefully expired after the expiration of a normal tidal volume 1000ml

40
Q

FEV1 full name and explanation?

A

Forced Expiratory volume in one second (dynamic volume)Volume of air that can be expired during the first second of expiration in an FVC

41
Q

FVC stands forExplanation

A

Forced vital capacitymaximum volume that can be forcefully expelled from the lung following a maximum inspiration

42
Q

FEV1 % (ratio) =

A

FEV1/FVC

43
Q

What type of curve can be used to determine FVC and FEV1

A

Volume time curve

44
Q

FEV1/FVC normal and asthmatic

A

Normal = >75%Asthmatic (obstructive) =

45
Q

FVC and FEV1 for restrictive disease

A

FVC = lowFEV1 = lowRatio = normal

46
Q

Airway flow =

A

F= change in pressure/ Resistance

47
Q

Sympathetic/ parasympathetic stimulation causes bronchoconstriction/ bronchodilation

A

Para. = bronchoconstrcitonSym. = bronchodilation

48
Q

Does airway resistance make it more difficult to inspire or expire

A

Expire

49
Q

What happens to the intracellular pressure during inspiration and expiration?

A

Inspiration = fallsExpiration = rises

50
Q

Why are the alveoli and airways compressed during active expirationWhat is this calledWho does this cause a problem for

A

Due to rising pleural pressureDynamic airway compressionPatients with airway obstruction

51
Q

What helps push air out of compressed airways

A

Increased pressure upstream increases the driving pressure between the alveolus and airway therefore pushing air out of the alveoli

52
Q

What happens during dynamic airway compression if there is an obstruction?

A

The driving pressure is lost over the obstructed segment causing a fall in the airway pressure along the airway downstream resulting in airway compression by the rising pleural pressure during active expiration (made worse if patient also has decreased elastic recoil of the lungs)

53
Q

What is a peak flow meter useful for assessing patients with?

A

Obstructive conditions

54
Q

Pulmonary compliance

A

measure of the effort that has to go into stretching or distending the lungs (volume change per unit of pressure change across the lungs)

55
Q

What does less compliant lungs mean?

A

More work is required to produce a given degree of inflation

56
Q

Some factors that decrease pulmonary compliance

A

pulmonary fibrosiSPulmonary oedemaLung collapsePneumoniaAbsence of surfactant

57
Q

What type of pattern can decreased compliance show in spirometry

A

Restrictive pattern

58
Q

When can compliance become abnormally increased

A

When the elastic recoil of the lungs is lost e.g. emphysema

59
Q

What happens to compliance as you age

A

It increases

60
Q

4 situations when work of breathing is increased

A

Pulmonary compliance is decreasedAirway resistance is increasedElastic recoil is decreasedneed for increased ventilation