Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Respiratory > Physiology of Respiratory > Flashcards

Physiology of Respiratory Flashcards

1
Q

What are the main functions of nasal breathing?

A

Heating and moistening the air

Removing particulate matter

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

How long does it take for inhaled particles to be removed?

A

15 minutes if they deposit in the nasal cavity and 60-120 days if they reach the alveolus

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

How does nasal breathing protect against bacterial infection?

A

Nasal secretions contain IgA antibodies, lyzosomes and interferons
Cilia also sweep the mucus gel rapidly to the back of the oropharynx where it’s swallowed

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

How do viruses attack the nasal airway?

A

They bind to receptors on the epithelial cells, most rhinoviruses bind to intercellular adhesion molecule 1 (ICAM-1) which is shared by neutrophils and eosinophils

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

What is Boyle’s Law?

A

At any constant temperature the pressure exerted by a gas varies inversely with volume of gas (as the volume of gas increases the pressure the gas exerts decreases)

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

The thorax and lungs are linked by what 2 forces?

A

The intrapleural fluid cohesiveness – water molecules in the intrapleural fluid are attracted to each other and resist being separated so the membranes tend to stick together
The negative intrapleural pressure – the sub-atmospheric intrapleural pressure creates a pressure gradient across the entire lung wall and chest wall hence the lungs are forced to expand out and the chest is forced to squeeze inwards

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

The main inspiratory muscles are

A

The diaphragm and external intercostal muscles (responsible for moving the ribcage and sternum)

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

What are the accessory muscles of inspiration? (when forceful inspiration is needed)

A

sternocleidomastoid, scalenus and pectoral

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

What happens in expiration?

A

The lungs recoil to their original shape and alveolar surface tension causing the intra-alveolar pressure to increase and air to leave the lungs

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

What are the accessory muscles for active expiration?

A

abdominal muscles and internal intercostal muscles

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

Where do the motor nervous discharges originate from?

A

The respiratory centre in the brainstem, they travel down the phrenic and intercostal nerves

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

What is the main driver of respiration in healthy individuals?

A

Arterial pH – closely linked to arterial CO2

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

How does airflow velocity change through the lung?

A

It decreases as you move to the periphery, it is greatest in the trachea and in the terminal bronchioles air only moves by diffusion

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

Tidal Volume (TV)

A

volume of air entering or leaving the lungs in a single breath

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

Inspiratory reserve volume (IRV)

A

extra volume of air that can be maximally inspired over and above typical resting TV

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

Expiratory reserve volume (ERV)

A

extra volume of air which can be actively expired by maximal contraction beyond the normal volume of air after a resting TV

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

Residual volume (RV)

A

minimum volume of air which remains in the lungs even after maximal expiration

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

Inspiratory Capacity (IC)

A

Maximum volume of air that can be inspired at the end of a normal quiet expiration IC=IRV + RV

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

Functional Residual Capacity (FRC)

A

Volume of air in lungs at the end of normal passive expiration FRC=ERV + RC

20
Q

Vital Capacity (VC)

A

maximum volume of air that can be moved out during a single breath following maximal inspiration VC=IRV + TV + ERV (very important measure)

21
Q

Total Lung Capacity (TLC)

A

Total volume of air the lungs can hold TLC=VC + RV. As residual volume can’t be measured by spirometry TLC can’t be measured by spirometry, residual volume will increase as elastic recoil of the lungs is lost e.g. in emphysema

22
Q

What stimulates the carotid and aortic bodies to cause respiration?

A

The arterial pressure of oxygen to be below 8kPa, this is known as hypoxic drive and doesn’t stimulate respiration in healthy people but does in some people with COPD

23
Q

What rhythm does airway tone show?

A

Carcadian

24
Q

What stimuli can result in bronchoconstriction via the vagus?

A 
Cigarette smoke
Solvents
Inert dust 
Cold air 
This is worse in asthmatic patients
25
Q

Alveolar pressure =

A

Pleural pressure + elastic recoil pressure of the lung

26
Q

Where is the ventilation and perfusion greater?

A

In the bases of the lungs rather than the apices

27
Q

What ratio of ventilation perfusion is optimum?

A

A match between V/Q

28
Q

What is the natural V/Q mismatch in heathy lungs?

A

Ventilation exceeds perfusion in the apices and perfusion exceeds ventilation in the bases

29
Q

What causes are there for V/Q mismatch?

A

Anatomical deadspace

Shunting of deoxygenated blood through the lung bypassing the alveoli

30
Q

Hypoxaemia is compensated for by

A

A physiological shunt causing more alveolar deadspace as increased ventilation of the well perfused areas wouldn’t help

31
Q

CO2 is carried in the blood as

A

Bicarbonate, carbamino compounds and in simple solution in a volume proportional to the partial pressure

32
Q

O2 is carried as

A

A chemical combination with haemoglobin in red blood cells in a non-linear relationship with the partial pressure

33
Q

Hyperventilation affects pCO2 by

A

Reducing PaCO2 due to the diffusion of CO2 out of the blood, therefore preventing hypercapnia

34
Q

Hyperventilation affects pO2 by

A

As haemoglobin is already saturated increase in alveolar PO2 will have no effect it won’t help to stop hypoxaemia due to physiological shunting

35
Q

What is the most common cause of arterial hypoxaemia?

A

V/Q mismatch

36
Q

What about the alveoli would make it difficult for the lungs to distend?

A

The surface tension which acts on the curved surface

37
Q

What substance helps to prevent alveolar collapse?

A

Surfactant produced by type II pneumocytes

38
Q

How does surfactant work?

A

It stops alveolar collapse by forming a thin monomolecular layer at the air-fluid interface

39
Q

What alveoli have the lowest chance of collapse?

A

The larger alveoli are where the surfactant has lowered the surface tension the most and therefore they will not collapse

40
Q

What is the purpose of sighs and deep breaths as part of normal breathing?

A

To reinflate the areas of the lung which have collapsed as part of normal breathing

41
Q

What can cause patchy basal lung collapse?

A

A fractured rib as the mechanism of sighs and deep breaths is disturbed preventing the reinflation of the collapsed alveoli

42
Q

What is respiratory distress syndrome of the new-born?

A

A condition which many premature babies suffer from because their lungs have not finished developing until birth. They don’t have proper perfusion to the lungs which is preventing the production of surfactant.

43
Q

How can pulmonary embolism lead to the characteristic areas of lung collapse?

A

Poor perfusion is thought to decrease surfactant production

44
Q

Forced Vital Capacity (FVC)

A

maximum volume that can be forcibly expelled from the lungs following a maximum inspiration

45
Q

Forced Expiratory Volume in 1 second (FEV1)

A

volume of air that can be expired during the 1st second of a FVC determination

46
Q

FEV1/FVC ratio

A

the proportion of the FVC which can be expired in the 1st second FEV1/FVC x 100 should normally be > 70%

Respiratory (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions