Brainscape's Knowledge GenomeTM

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


See full index

Respiratory Physiology > Quiz 6 > Flashcards

Quiz 6 Flashcards

1
Q

What are the three groups of neurons located in the brainstem?

A
  1. Dorsal Respiratory.
  2. Ventral Respiratory.
  3. Pneumotaxic center
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which neuron group plays the most fundamental role in control of breathing?

A

Dorsal Respiratory

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

Which two nerves deliver sensory information to DRG

A

The Vagal (X) nerve and Glossopharyngeal (IX)

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

What is an inspiratory RAMP signal?

A

Motor signal transmitted from the DRG to the diaphragm is NOT an instantaneous action potential burst. Begins weakly and increases (ramp like) manner for 2 seconds to cause contraction of diaphragm.

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

What does the pneumotaxic center do for breathing?

A

Functions to limit inspiration phase of breathing cycle and secondarily to increase rate of breathing.

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

How does the VRG function differently from DRG?

A

VRG inactive during normal quiet respiration.

Stimulates abdominal muscles to assist in forced exhalation. Contributes to respiratory drive but NOT rate

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

What is the Hering-Breuer Reflex ?

A

Protective feed-back reflex which limits the over inflation of lungs. This reflex also increases the rate of respiration (versus size of breath)

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

What does excess carbon dioxide do to the respiratory center?

A

Act directly on respiratory center to increase strength of both inspiratory and expiratory motor signals.

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

Does oxygen have a direct effect on respiratory centers?

A

No

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

Where does oxygen have its effect for respiratory drive?

A

On peripheral chemoreceptors in carotid and aortic bodies

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

Which has a greater effect on stimulating chemosenstiive neurons- pH or CO2?

A

CO2 is believed to cause stimulation of these neurons.

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

What is the relationship of CO2 between the blood and the brain?

A

CO2 is highly permeable to blood-brain barrier so blood and brain concentrations are equal

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

How does chronic increased CO2 concentration differ from acute?

A

Changes in blood CO2 concentration has potent acute effect on controlling respiration drive but a weak chronic effect after a few days of adaptation

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

What type of patient might have blunted responses to increased CO2

A

Chronic Obstructive Pulmonary Disease

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

Which has a greater effect on alveolar ventilation- PCO2 or pH?

A

PCO2 changes rapidly change in rate of pulmonary ventilation

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

Does oxygen have an effect on respiratory center to alter respiratory drive?

A

No changes in oxygen have virtually no direct effect on respiratory center.

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

At what PO2 are peripheral chemoreceptors sensing a low oxygen level?

A

Blood oxygen levels below PO2 of 70mmHg are sensed by peripheral chemoreceptors

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

Where are the two major peripheral chemoreceptors located?

A

Carotids and aorta

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

Which afferent nerve fiber sense back to DRG from the carotid bodies?

A

CN IX (glossopharyngeal)

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

Which afferent nerve fiber sense back to DRG from the Aortic body?

A

CN X (vagus nerve)

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

What is acclimatization?

A

When mountain climbers slowly ascend to higher elevation to withstand lower atmospheric oxygen concentrations.

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

How does low arterial oxygen effect ventilatory drive?

A

When CO2 and pH remain normal; ventilatory drive y low blood oxygen content is not significant until PO2 falls below 100mmHg.
Ventilation doubles when PaO2 falls below 60mmHg

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

What causes increase in ventilation during exercise?

A

Multiple factors:
Muscle/joint movement proprioceptors send.
Hypoxia in muscles elicits afferent nerve signals to excite resp center.
PCO2 and PO2 changes stimulate respiration

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

What are Lung J Receptors?

A

Sensory nerve ending in alveolar walls juxtapose the pulmonary capillaries.
They become stimulated when engorged by blood or with pulmonary edema occurring in CHF.
Their excitation may give the feeling of dyspnea

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

How does brain edema effect breathing?

A

Resp center activity is depressed or inactivated by acute brain edema.
Blood flow reduction affects cellular metabolism and function.
Cheyne-Stokes breathing is the terminology?

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

What causes Cheyne-Stokes breathing?

A
  1. Long delay in transport of blood from lungs to brain (Low CO).
  2. Increased negative feedback gain (brain damage) due to hypoxia or severe metabolic abnormality.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

At what PaCO2 and PaO2 does the nervous system try to keep the blood at?

A

PaCO2=40 and PaO2=100

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

What does the DRG control?

A

Inspiration and respiratory rhythm.

29
Q

Which 2 nerves deliver sensory information to DRG?

A

Vagal and Glossopharyngeal

30
Q

What three sources send signals to DRG?

A
  1. Peripheral chemoreceptors.
  2. Baroreceptors.
  3. Lung receptors
31
Q

Is motor signal from DRG to diaphragm an instantaneous action potential burst or not?

A

It is not an instantaneous action potential burst

32
Q

What is a RAMP signal?

A

Motor signal from DRG to diaphragm. It ‘ramps’ up (not instantaneous)

33
Q

Why is the RAMP signal good?

A

It causes a steady increase in inspiratory volume

34
Q

What happens to the RAMP signal from DRG to diaphragm after it signals a breath?

A

It abruptly stops for next 3 seconds to allow relaxation of diaphragm

35
Q

What are the two ways the RAMP is controlled/altered?

A
  1. Control of the rate of ramp signal increase. (lungs fill more rapidly).
  2. Control of limiting point at which ramp ceases (increase frequency)
36
Q

What does the pneumotaxic center do for breathing?

A

Limits inspiration phase of breathing cycle and therefore increases the rate of breathing

37
Q

What happens with a weak pneumotaxic signal?

A

Longer inspiration time
&
Reduced RR

38
Q

What happens with a strong pneumotaxic signal?

A

Shorter inspiration time
&
Increased rate

39
Q

Does the VRG help with normal quiet respiration?

A

No; the VRG is inactive during normal quiet respiration and does not participate in basic rhythmic oscillation which controls respiration.

40
Q

What does the VRG do for respiration?

A

Stimulates the abdominal muscles to assist in forced exhalation

41
Q

What is the Hering-Breuer Reflex?

A

Protective feed-back reflex that limits over-inflation of lungs

42
Q

Which nerve transmits signals to DRG when lung is overstretched? (Hering-Breuer Reflex)

A

Vagus nerve

43
Q

What is the ultimate goal of respiration?

A

Maintain proper concentrations of oxygen, carbon dioxide, and hyrodgen ions in the tissues

44
Q

Which molecule acts directly on the respiratory center to increase strength of both inspiratory and expiratory motor signals?

A

Carbon Dioxide

45
Q

Where does the Oxygen molecule have a direct effect on breathing?

A

Peripheral chemoreceptors in carotid and aortic bodies

46
Q

What area of the brainstem is highly sensitive to CO2 changes?

A

Ventral Medulla surface

47
Q

Changes in blood CO2 concentration has weak (chronic or acut) effects after a few days on controlling respiration drive, but potent (chronic or acute) effect on controlling respiration drive?

A

Weak=chronic.

Potent=acute

48
Q

What is the CO2 of the brain if the CO2 of the blood is 30?
40?
60?

A

30, 40, 60

49
Q

Which molecule actually has a potent direct effect on chemosensitive areas of the brain stem? (NOT CO2)

A

H+ ions

50
Q

What happens to CO2 in interstitial fluid of medulla or CSF?

A

CO2 and H20 create carbonic acid. This gets broken down into H+ and HCO3 ions

51
Q

Which has a greater effect on alveolar ventilation, PaCO2 or pH?

A

PaCO2 has a greater effect and more rapid effect.

52
Q

At what PO2 do peripheral chemoreceptors sense as low?

A

PO2<70

53
Q

Carotid sends nerve impulse via what nerve to DRG?

A

CN IX= Glossopharyngeal

54
Q

Aorta sends nerve impulse via what nerve to DRG?

A

CN X=Vagus nerve

55
Q

What is faster/what is stronger- stimulation of central respiratory groups or peripheral chemoreceptors via CO2 and pH?

A

5 times faster via peripheral chemoreceptors.

7 times stronger via central receptors

56
Q

If CO2 and pH remain normal, at what point does PO2 level double ventilation efforts?

A

at 60mmHg

57
Q

What muscles are stimulated by the VRG?

A

Abdominal muscles for forced expiration

58
Q

What happens to the CO2 curve as exercise is began?

A

Initially PCO2 decreases.
Then begins to increase with exercise.
Alveolar ventilation picks up and tries to drive CO2 down.

59
Q

What are the two factors that are interrelated during exercise?

A

Neurogenic factors stimulat O2 supply and CO2 removal.

Chemical factors provides adjustment to keep CO2 and pH normal

60
Q

Is voluntary control of respiration mediated through respiratory center?

A

No; Cortex and higher centers downward through cortispinal tract to spinal neurons that drive respiratory muscles.

61
Q

Which receptors are stimulated when engorged with blood or when pulmonary edema from CHF occurs?

A

Lung “J Receptors”

62
Q

What ‘might’ the J Receptors role be?

A

Their excitation may give the feeling of dyspnea.

63
Q

What are two treatments for brain edema?

A

Hyperventilation and hypertonic diuresis.

64
Q

Describe Cheyne-Stokes Breathing:

A

Pattern of short intervals of deep breathing followed by periods of shallow or absent breaths.

65
Q

What causes the cyclical presentation of Cheyne-Stokes breathing?

A

Over breathing causes low CO2 and high O2 in lungs.
Transmitted to brain as excess ventilation so response to to slow down. The pause causes increased CO2 and low O2 which started the process over again

66
Q

Which two pathological cause Cheyne-Stokes breathing?

A
  1. Low CO (delay in transport of blood from lungs to brain.

2. Brain damage/Stroke (increased negative feedback gain due to hypoxia or severe metabolic abnormality.

67
Q

Who has the potential for Cheyne Stokes breathing?

A

The potential for C-S breathing is present in everyone.

68
Q

What patients are at increased risk of C-S breathing?

A

Stroke and heart failure patients

Respiratory Physiology (7 decks)

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