Brainscape's Knowledge GenomeTM

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


See full index

respiratory > Physiology > Flashcards

Physiology Flashcards

1
Q

what does medulla rhythmicity control?

A

basic level control
inspiratory (DRG) and expiratory areas (VRG)

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

what is the pneumotoaxic area?

A

helps coordinate the transition between inspiration and expiration

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

what is the apneustic group?

A

sends impulses to inspiratory area that activate it and prolong inspiration and inhibit expiration

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

what is the dorsal respiratory group?

A

input from IX and X nerves into medulla
input ends inspiration

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

what is ventral respiratpry group?

A

inactive in normal/ quiet breathing as DRG is active
expiration is passive
activity increases with exercise, dyspnoea, lung disease

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

what is the function of respiratory control?

A

maintain homeostasis - gases/ pH
maximises mechanical activity for efficiency
adapts to needs
speech, coughing, exercise, disease

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

what does cortical control include?

A

brainstem control - pons medulla
ventilatory pump - resp muscles
sensors - chemoreceptors/ mechanoreceptors

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

what is the function of cortical control?

A

negative feedback
modifies amount and type of breathing
modifies chemical and mechanical state

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

where are the two higher centres responsible for rhythm control?

A
  1. cerebral cortex
  2. hypothalamus and limbic system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what does the cerebral cortex do in relation to rhythm control?

A

voluntarily changes breathing patterns, overridden by stimuli of increased arterial [H+] and [CO2]
- if you hold breathing then faint, normal breathing continues - kids who hold breath, brainstem will override

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

what does the hypothalamus and limbic system do in relation to rhythm control?

A

emotional changes

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

how does ventilation rate and depth increase?

A
  • Voluntary hyperventilation by cerebral cortex
  • Anticipation of activity via stimulation of limbic system (behaviour and emotion)
  • Increase in arterial [H+] above 40mmHg, dramatic decrease in O2 detected by central and peripheral chemoreceptors
  • Increase in sensory impulses from proprioceptors in muscles and joints and increase in motor impulses from motor cortex
  • Decrease in blood pressure detected by baroreceptors
  • Increase in body temp
  • Prolonged pain
  • Stretching and sphincter
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

how does ventilation rate and depth decrease by?

A
  • Voluntary hypoventilation controlled by cerebral cortex
  • Decrease in arterial [H+]
  • Decrease in sensory impulses from proprioceptors (movement receptors) in muscles and joints and decrease in motor impulses
  • Increase in Bp detected by baroreceptors
  • Severe pain (nociceptors) causes apnoea
  • Irritation of pharynx/ larynx by touch/ chemicals causes apnoea followed by coughing/ sneezing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are the two types of peripheral chemoreceptors?

A

carotid and aortic

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

what is the role of the peripheral chemoreceptors?

A

send signals via glossopharyngeal (carotid) and aortic (vagus)
respond by altering firing rate
negative feedback mechanism
respond to O2, pH and hypercapnia

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

how does the peripheral chemoreceptor’s respond to oxygen?

A

respond to PaO2 - drop must be very dramatic so it doesn’t interact with daily breathing
hypoxia potentiates other responses

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

how does peripheral chemoreceptors respond to arterial pH?

A

more sensitive response
more [H+] - acidosis - more firing for more ventilation
less [H+] - alkalosis - decreased ventilation

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

how does peripheral chemoreceptors respond to CO2?

A

can respond to hypercapnia but fairly insensitive

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

describe the carotid bodies?

A

both small nodules (2mg), highest blood flow in any tissue
very high metabolic rate
type I glomus cells - chemosensitizer cells of carotid
can detect hypoxia - only peripheral chemoreceptor which can

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

what effect does the aortic chemoreceptors have?

A

systemic
can lower blood flow - affected by anaemia, sepsis, hypotension

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

what is the role of central chemoreceptors?

A

main source of tonic drive (slow/ graded) quiet breathing - eupenic control
powerful influence on respiratory centre - primary source for feedback for assessing ventilation effectiveness

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

what do central chemoreceptors primarily respond to?

A

PaCO2 - changes to CSF pH
insensitive to hypoxia

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

what is chronic hypercapnia?

A
  • Respiratory acidosis
  • Bicarbonate compensations return the brain pH back to normal so central chemoreceptors are less sensitive to further changes in PaCO2
  • Central chemoreceptors drive depressed – minute ventilation depends on hypoxia via carotid bodies
  • If pure O2 given – depresses carotid response and will reduce hypoxic ventilation drive
  • Could depress ventilation, increase PaCO2, induce come (CO2 narcosis)
  • Increase in partial pressure above 45mmHg
  • Causes – COPD, lung diseases, renal impairment – decompensation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what does chronic hypercapnia do to ventilation?

A

chemoreceptor adaptation and depressed ventilation

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

how does the parasympathetic NS control respiration?

A

slows breathing rate down
causes bronchial tubes to narrow and pulmonary vessels to widen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

how does sympathetic NS affect respiration?

A

increases breathing rate
causes bronchial tubes to widen and pulmonary blood vessels narrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what do sensors within airways do?

A

detect lung irritants
sensory trigger sneezing/ coughing
chemoreceptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what is central sleep apnoea?

A

brain temporarily stops sending muscles needed to breathe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what is hypoxemia?

A

low oxygen levels within the blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what is hypoxia?

A

low oxygen levels within tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what can cause hypoxemia?

A

ventilation/ perfusion mismatch
diffusion impairments - emphysema, scarring of the lungs
hypoventilation
low oxygen environments
right to left shunting

32
Q

what is partial pressure?

A

pressure of single type of gas within a mixture

33
Q

what is daltons law?

A

behaviour of gases when they come into contact with liquid
conc of gas in a liquid is directly proportional to the solubility and partial pressure of that gas

34
Q

what is ventilation?

A

movement of air in and out the lungs

35
Q

what is perfusion?

A

flow of blood in the pulmonary capillaries

36
Q

what factors are important for good gas exchange?

A

pressure gradient - allows the movement
thin capillary membrane and thin alveoli
alveoli have large surface area

37
Q

what occurs during times of poor ventilation?

A

body redirects blood flow in alveoli to areas of better ventilation - constricts bronchioles to direct
arteries serving alveoli with good ventilation will vasodilate - greater blood flow

38
Q

what is external respiration?

A

occurs at alveoli

39
Q

what is internal respiration?

A

gas exchange at tissues

40
Q

what do central chemoreceptors detect?

A

detect change in CO2/ H+ within brain

41
Q

what do peripheral chemoreceptors detect?

A

faster detection responds to changes in PO2 and PCO2
sense hypoxia

42
Q

what can acute exacerbations of asthma be triggered by?

A

resp viruses. Can be bacterial infections, allergens, pollutants and occupational exposure

43
Q

which sex is more likely to develop asthma during childhood?

A

male

44
Q

which sex is more likely to have persistent asthma into adulthood?

A

female

45
Q

when is asthma worse during the day?

A

diurnal - at night or early morning

46
Q

what resp conditions could be potential differential diagnoses?

A

bronchiectasis, COPD, fibrosis, PE, infection (pertussis and TB), lung cancer

47
Q

what is a differential diagnosis GI related for asthma?

A

gastro-oesophageal reflux

48
Q

what is a cardiac differential diagnose for asthma?

A

HF

49
Q

why would a sputum sample be useful for asthma diagnosis?

A

blood clots
bacterial infection - green

50
Q

what FEV1/FVC score would indicate asthma?

A

<70%

51
Q

what decrease in FEV1 between no treatment and then bronchodilator would indicate asthma?

A

improving by 12%

52
Q

what is the use of fractional exhaled NO?

A

confirms eosinophil inflammation within asthma

53
Q

what should be included within an annual asthma reveiw?

A

symptoms/ control, smoking status, inhaler technique and adherence. PEFR and vaccination status (should be up to date). Lifestyle – smoking cessation and healthy BMI promoted

54
Q

what would you put inside an inhaler?

A
  • Inhalers: lowest possible dose of inhaled steroid – escalate as appropriate
    1. Symptomatic asthma – short acting beta 2 agonist (SABA) as required
    2. Add low dose of inhaled corticosteroid (ICS)
    3. Add long acting beta 2 agonist (LABA)/ trial of leukotriene receptor antagonist (LTRA)
    4. Increase dose of ICS or trial TTRA
    5. ICS increased to high and specialist
    6. Specialist – theophylline/ biologic agents
55
Q

what are complications of asthma?

A

pneumonia, collapse and pneumothorax, resp failure, status asthmaticus

56
Q

what is status asthmaticus?

A

emergency - asthma exacerbation

57
Q

what happens if the pressure drops across the lungs?

A

lung will collapse

58
Q

what is intrapleural pressure?

A

pressure in pleural cavity (less than atmospheric – more negative). Pressure between parietal and visceral. It does change during different phases of breathing

59
Q

what is intra-alveolar pressure?

A

pressure within alveoli, which changes depending on phases of breathing. Alveoli are connected to atmosphere via tubing or airways. The interpulmonary pressure of alveoli always equalised with atmospheric pressure

60
Q

what is transpulmonary pressure?

A

difference between intrapleural and alveolar pressure. A higher transpulmonary lung would indicate a larger lung

61
Q

what is more soluble in water O2 or CO2?

A

Carbon dioxide is more soluble in water than oxygen
- Oxygen is mainly bound to haemoglobin
- Carbon dioxide is primarily bicarbonate

62
Q

define pneumonia

A

infection triggering inflammation which causes capillaries to leak hence the fluid. It is characterised by consolidation

63
Q

how is diffusion defined by Ficks Law?

A

by Fick’s Law: gas flow, diffusion area, thickness, diffusion constant sol-das solubility and gas molecular weight.

64
Q

what fluid lines alveoli?

A

surfactant
- Layer of fluid lining alveoli – some mucus. Not thick and helps with O2 diffusion

65
Q

what happens with more fluid gathers around alveoli?

A
  • Pathology is when this fluid thickens – extra fluid or more mucous build up – caused by infection, fibrosis
66
Q

what is bulk flow?

A

process used by small lipid- insoluble proteins to cross capillary walls
- Alongside diffusion this is responsible for most gas transport

67
Q

does anaemia effect diffusion with gas exchange?

A
  • Diffusion of gases will be affected by condition of alveolar membrane and increases with blood flow and decreases with anaemia (diffusion is dependent on blood supply)
68
Q

what is the oxygen dissociation curve?

A

Oxygen dissociation curve – the haemoglobin affinity for oxygen

69
Q

why would the oxygen dissociation curve shift to the right?

A
  • Shift to right: reduced affinity - gives up oxygen more easily – high CO2, lower pH, higher temp (in fever, haemoglobin gives up oxygen more easily to help keep tissues perfused)
70
Q

why would the oxygen dissociation curve shift to the left?

A
  • Shift to left: higher affinity – prevents oxygen leaving haemoglobin – lower CO2, higher pH, lower temp
71
Q

what are the 4 things contributing to hypoxaemia?

A
  1. Hypoventilation – less oxygen getting in – reduced resp rate
  2. Diffusion – gas exchange issues eg fluid (pneumonia) or NO (anaesthetic)
  3. Shunt – blood supply has been redirected
  4. Ventilation – perfusion mismatch: the amount of oxygen going to alveoli doesn’t match the blood supply to remove the oxygen
72
Q

what occurs in left to right pulmonary circulation shunt?

A
  • Left -right shunts: true anatomical – blood form bronchial circulation joins pulmonary vein. Some coronary venous blood drains into LV. Disease – shunting can be greater
73
Q

describe the apex of the lung in terms of ventilation

A
  • More negative intrapleural pressure – more pulling
  • Alveoli have larger volume
  • Smaller compliance – less elastic
  • Less ventilation
74
Q

describe the base of the lung in terms of ventilation?

A
  • Less negative intrapleural pressure
  • Alveoli with smaller volume and more of them
  • Larger compliance – more elastic
  • More ventilation
    There is more blood flow and the base of the lung
75
Q

can hypoxia vasoconstriction help with severity of mismatch?

A

yes can redirect blood to areas of better match

76
Q

what can regions of lower V/Q result in?

A

in constriction of airways, inflammation and secretion

respiratory (10 decks)

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