Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

PHYL 4504 > Control of Breathing > Flashcards

Control of Breathing Flashcards

(92 cards)

Start Studying
1
Q

what are the three elements of respiratory control?

A

Sensors, Central controller, Effectors

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

WHat do sensors do?

A

gather information and feed it up

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

What does the central controller in the brian do

A

coordinates informaiton and sends inpulses down

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

What does the effectors do?

A

affect ventilation (respiratory muscle)

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

in the medulla: dorsal respiratory group (DRG)

A

nucleus tractus solitarius - recieved afferent input from 9th and 10th cranial nerves

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

in the medulla - ventral respiratory group (VRG)

A

rostral nucleus retrofacialis, caudal nucleus retroambiguus, nucleus paraambiguus, contains both inspiratory and expiratory neurons

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

Inspiration begins with _____

A

increased discharge from cells in nucleus tractus solitarius, nucleus retroambiguus and nucleus paraambiguus - leads to contraction of respiratory muscles

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

at the end of inspiration -

A

decrease in neuronal diring results in relaxation of respiratory muscles = exhalation

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

Basic rhythm of respiration is set by

A

DRG

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

DRG mainly causes

A

inspiration

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

VRG mainly causes

A

expiration

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

Pneumotaxic area is in the ____ and mainly controls ___ and _____

A

superior pons…. rate and depth of breathing

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

during normal respiration, nervous signals start ___ and then ____ steadily

A

weakly and increase steadily - ramps up for 2 seconds - inspiration

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

nervous signal ceases for next 3 seconds, which turns off the excitation to the diaphraghm which permits…

A

elastic recoil of chest wall and lungs = expiration, cycle repeats

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

a ramp allows what?

A

steady increase in volume of lungs rather than a sudden gasp

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

inspiratory ramp input can be controlled by

A

increase rapidly so lungs can fill rapidly…

limit point at which ramp suddenly turns off - increases the ventilatory frequency

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

Pneumotaxic area is located…

A

dorsally in the nucelus parabrachialis of upperpons

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

pneumotaxic area send inputs to..

A

inspiratory area

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

pneumotaxic area controls the..

A

switch off point of respiratory ramp, so controlling the duration of the filling phase of the breathing cycle

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

when pneumotaxic signal is strong…

A

inspiration is short

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

when signal is weak

A

inspiration last longer, overfilling the lungs

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

the function of the pneumotaxic area is to

A

limit inspiration and so regulate inspiratory volume

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

secondary effect on pneumotaxic area is to

A

increase breahting rate - limiting inspiration also shortens expiration, so frequency increases

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

penumotaxic area may also_ ______ the respiratory rhythm because a normal rhythm can exist in its absence

A

fine tune

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What other factors affect respiration
cortex, pulmonary mechanoreceptors
26
the cortex can override the brainstem to a point how does this affect PaCO2
hyperventilation decreases PaCO2 resulting in alkalosis - hypoventilation results in changes
27
pulmonary mechanoreceptors - herring breuer inspiratory inhibitory reflex
stimulated by increases in lung volumes, especially those associated with increases in ventilatory rate and tidal volume
28
herring breuer inspiratory inhibitory reflex
stretch reflex mediated by vagal fibres, and results in cessation of inspiration by activation of "off" neurons in medulla. Inactive during quiet breahting - important in newborns
29
Diving reflex
cold water stimulates nasal or facial receptors to stop breathing (apnea) which protects against aspiration of water
30
Sneeze reflex
receptors in nose
31
aspiration or sniff reflex
stimulation of mechanical receptors in nasopharynx and pharynx. strong short duration inspiratory effort that moves material from nasopharynx to pharync, swallowed
32
hering breuer inflation reflex..
inspiratory inhibitory reflex that arises from afferent sretch receptors located in ASM - reflex effect is to slow respiration via increase in expiratory time, becomes activated when tidal volume exceeds 1500mL (vagal nerve),negative feedback mechanism
33
what are the three sensory receptors in the tracheobronchial tree that respond to stimuli to affect aspects of pulmonary physiology?
Irritant receptors, slowly adapting pulmonary stretch receptors, and juxta-alveolar capillary (J) receptors
34
Irritant receptors
rapidly adapting pulmonary stretch receptors: stimulated by inhaled dust, noxious gas and cigarette smoke
35
where are irritant receptors located?
in trachea and large airways - located between epithelial cells lining airways - transmit information via myelinated vagal afferent fibres
36
Stimulation of irritant receptors results in
increase in airway resistance via reflex constriction stimulation, activated musce, reflex apnea and cough
37
slowly adapting pulmonary stretch receptors respond to
mechanical stimulation, activated by lung inflation
38
slowly adapting pulmonary stretch receptors transmit information via
myelinated vagal afferent fibres
39
Juxta-alveolar capillary receptors are located
in alveolar walls, near capillary bed
40
J receptors are activated by
engorgement of pulmonary capilaries with blood and increases in interstitial fluid volume - results in an increased breathing rate
41
J receptors mediate the change in ___
breathing pattern, inducing rapid, shallow breathing a sensation of dyspnea
42
Joint and muscle receptors
mechanoreceptors in joints and muscles that detect movement of limbs and instruct the inspiratory centre to increase breathing rate - important in the early response to exercise (annticipatory)
43
What is dyspnea?
Subjective feeling of shortness of breath
44
Sensors - Chemoreceptors are located where?
peripheral - carotid and aortic bodies
45
What to chemoreceptors do?
trasmit afferent information to central resp control centre - only chemoreceptor that responds to changes in PO2 - repsonsible for 40% of ventilatory response to CO2 - small and highly vascularized structures
46
Chemoreceptors are made up of what cells?
type 1 (glomus) cells - rich in mitochondria and ER and cytoplasmic granules containing NTs DA, ACh, NE and neuropeptides
47
What to type 1 glomus cells sense
PO2, PCO2 and pH - respond to arterial levels, not venous
48
What are chemoreceptors stimulated by?
decrease PO2, increase H+, increase PCO2
49
There is a _____ response to PO2
non-linear
50
Stimulated to increase breathing rate for what 3 things
significantly decreased PO2 (hypoxia) - less than 60mmH, decrease arterial pH (metabolic acidosis) - resp compensation- independent of changes in arterial PCO2 and mediated by carotid bodies, increase PCO2 (resp acidosis) - less inportant response, but rapid and useful in matching ventilation to abrubpt changes in PCO2
51
What happens if response to arterial PO2 is not present
severe hypoxemia may depress ventilation - ex: bilateral carotid body resection - complete loss of hypoxic ventilatory drive
52
people exposed to chronic hypoxia develop ___
carotid body hypertrophy
53
Chemoreceptors - central - on the ventral surface of the medulla respond to
directly to changes in the pH of CSF and indirectly to changes in arterial PCO2
54
decrease in pH leads to
increased breathing rate
55
what are the most important receptors involved in minute to minute control of ventilation
central chemoreceptors
56
central chemoreceptors are surrounded by
brain ECF - composition of ECF governed by CDF, local bood flow, and metabolism
57
CSF deperated from blood by
Blood brain barrier - impermeable to H+ and HCO3-, but not CO2
58
As blood pH increases, CO2 does what?
diffuses into CSF and H+ ions are generated
59
Normal CDF pH =
7.32
60
CSF contains less _____ so it has less ____ capacity
proteins, buffering
61
What is the most important factor for control of ventilation
PCO2 arterial - very sensitive - held within 3mmHg
62
Ventilatory response to PCO2 is reduced by
sleep, increasing age, exercise tolerance, barbituates
63
Increased depth and rate of ventilation due to
central chemoreceptors and peripheral chemoreceptors
64
PaCO2 greater than 100mmHg is a respiratory ___
depressant
65
Ventilation increases rapidly when PCO2 increases, what does lowering PO2 do
ventilation is higher and slope is steeper
66
Alveolar PO2 can fall to ___ before increased ventilaiton occurs
50mmHg
67
increasing PCO2 ____ ventilation at an PO2
increases
68
When PCO2 increases, a PO2 less than 100 mmHg causes
some stimulation of ventilation via peripheral chemoreceptors
69
when you increase PCO2 and breath a hypoxic gas mixture, ventilation ____
increases more rapidly
70
patients with compensated metabolic acidosis have lower pH and low PCO2 show
increased ventilation (reduced PCO2)
71
OSA
obstructive sleep apnea
72
apnea results in
significant decreases in PO2 and increases in PCO2
73
most common type of sleep apnea
OSA
74
when does OSA occur?
when the upper airway (hypopharynx) closes during inspiration
75
OSA is similar but more severe than ___
snoring
76
Airway is ____ and airflow___
totally obstructed, stops
77
X and Y also occur in OSA
hypercapnia and hypoxemia
78
Pleural pressure osciallations ____ as CO2 rises
increases
79
resistance to airflow is very ____ as a result of the upper airway obstruction
high
80
Risk factors for OSA
age, male, obesity, increased neck circumference, alcohol and sedative use, weight gain and craniofacial abormalities
81
Symptoms of OSA
daytime sleepiness, restless sleep, morning dry mouth and headaches, mod changes, snoring, nocturnal chocking and cardiac arrhythmia, erythorcytemia
82
Treatment for OSA
CPAP, dental appliances, surgery
83
Central sleep apnea is characterized by
breathing that stops and starts during sleep
84
CSA occurs when
CNS drive to the ventilatory muscles transiently stops
85
What is the difference between OSA and CSA
lack of resp effort in CSA
86
Causes of CSA
damage to central resp areas or abnormalities of the neruomuscular aparatus, high altitude
87
Repeated epidosed of apnea during which patient makes ___
no resp effort
88
no attempt to breath demonstrated by ___
lack of oscilations in pleural pressure
89
Breathing pattern - when remove sensory input from lungs
cycle is lengthened and tidal volume increased so alveolar ventilation is not affected
90
Apneustic breathing
input from cerebral cortex and thalamus eliminated with vagal block = loss of resp inhibition activity results in loss of inspiratory drive = prolonged inspiration activity broken after several second by brief expiration (apneusis)
91
Cheynes Stokes breathing
abrnormality of ventilatory control, varying tidal volume and centilatory frequency - after apnea, VT and resp frequency increase over several breaths, then decrease until another apnea
92
What changes in blood gas occur in cheynes stokes breathing
increase PACO2 decrease PAO2

PHYL 4504 (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions