Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

555- Physiology & Pathophysilogy > Exam 9 - Short Term Control Of BP > Flashcards

Exam 9 - Short Term Control Of BP Flashcards

(44 cards)

Start Studying
1
Q

Local flow to tissues

A
  • Depends on constant pressure drop across tissues

- MAP - CVP = constant

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

Arterial compliance

A

2 mls/mmHg

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

Venous compliance

A

100 mls/mmHg

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

Hormonal mechanisms for controlling BP

A
  • Aldosterone

- Renin-angiotensin-vasoconstriction

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

Nervous mechanisms for BP control

A
  • Baroreceptors (moment to moment / normal changes)
  • Chemoreceptors
  • CNS ischemic response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Physiologic mechanisms for BP control

A
  • Capillary fluid shift (normal to abnormal changes)

- Stress relaxation of vasculature (normal to abnormal changes)

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

Renal mechanism for BP control

A
  • Renal-blood volume pressure control

- long term control….everything else short term

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

Filtration/absorption rate

A
  • If MAP increase….filtration increase

- If MAP decrease….absorption increase

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

4 quickest activated mechanisms

A
  • Within seconds
  • Baroreceptors
  • Chemoreceptors
  • CNS ischemic response
  • Stress relaxation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

2 average reaction time mechanisms

A
  • Within minutes
  • Renin-angiotensin-vasoconstriction
  • Capillary fluid shift
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

2 slowest reacting mechanisms

A
  • Within hours
  • Aldosterone
  • Renal-blood volume pressure control
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

5 average strength mechanisms

A
  • Max feedback of 4% increase relative
  • Bring BP back CLOSE to normal
  • Chemoreceptors
  • Stress relaxation
  • Renin-angiotensin-vasoconstriction
  • Capillary fluid shift
  • Aldosterone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

2 strong mechanisms

A
  • Max feedback of 7 & 11
  • Bring BP back CLOSE to normal
  • Baroreceptors
  • CNS ischemic response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

1 infinite strength response

A
  • Renal-blood volume pressure control

- Can bring BP back to NORMAL

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

Which mechanisms play role on bypass

A
  • All except Aldosterone and Renal-blood volume pressure
  • CPB not on long enough to activate those two
  • Average case only 90 minutes
  • These two take 4 hours to activate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Which change in BP to these mechanisms respond to

A
  • Mostly drops in BP

- Except Baroreceptors…they do both

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

Innervation of the heart

A
  • Sympathetic and Parasympathetic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Innervation of arterioles

19
Q

Parasympathetic control

Study These Flashcards
A
  • Regulates HR
  • Small/No affect on contractility
    - only atrial filling
  • Minimal regulation of circulation
20
Q

Sympathetic control

Study These Flashcards
A
  • Regulate contractility

- Regulates circulation

21
Q

Vasomotor center pathways

Study These Flashcards
A
  • Efferent pathways
  • Parasympathetic impulses via vagus nerve
  • Sympathetic impulses via spinal cord and peripheral sympathetic nerves to arteries, arterioles, and veins
22
Q

Sympathetic nerve fibers

Study These Flashcards
A
  • Exit spinal cord via thoracic spinal nerves and first 2 lumbar
  • Enter sympathetic chains either side of spinal cord
  • To circulation 2 ways:
    • specific nerves directly to heart and internal viscera
    • peripheral portions of spinal nerves to peripheral vasculature
23
Q

Which vessels innervated by sympathetic

Study These Flashcards
A
  • Arteries / Arterioles - change resistance and flow to tissue
  • Veins / Venuoles - change volume held…changing return
  • SOME metarterioles and pre-cap sphincters of mesenteric
    - most are not
  • Most are vasoconstrictors: kidney/ intestines/ spleen/ skin
    - weak vasoconstriction in skeletal muscle / brain
  • When impulses sent to vessels…also sent to adrenal medulla
    - releases Epi and NE
24
Q

Vasomotor center location

Study These Flashcards
A
  • Bilateral
  • all efferent neurons come out of here
  • In medulla and lower third of pons
  • regulates amount of vascular constriction AND cardiac activity
    - like HR and contractility
25
3 parts of vasomotor center
- Vasoconstrictor - Vasodilator - Sensory
26
Vasoconstrictor area
- Bilateral - Anterolateral part of upper medulla - sends out efferent neurons to all areas of spinal cord - excite vasoconstrictor neurons of sympathetic - increase cardiac activity (sympathetic)
27
Vasodilator area
- Bilateral - Anterolateral part of lower medulla - Sends efferent neurons to vasoconstrictor area - fibers inhibit vasoconstrictor area - decrease cardiac activity (parasympathetic)
28
Sensory area
- Bilateral - In medulla and lower pons (tractus solitarius) - Receives signal via vagus and glossopharyngeal nerves - Sends output to vasoconstrictor and vasodilator areas - based on input from circulatory system
29
Vasomotor center cardiac control
- Lateral portions: excitatory impulses to heart - Sympathetic - Medial portion: impulses to vagus nerve which sends parasympathetic impulses to heart -> inhibitory - Parasympathetic
30
Sympathetic vasoconstrictor tone
- more impulses -> constrict - less impulses -> dilate - vasoconstrictor center sends 1.5-2.0 impulses/sec - normal vasomotor tone - If efferent paths blocked....MAP will drop by at least half
31
Vasomotor center control by CNS
- Pons / mesencephalon / diencephalon - lateral/superior portions: excite - medial/inferior portions: inhibit - hypothalamus - posterolateral: excite - anterior: mild excite or inhibit.....depends which part - cerebral cortex - motor cortex: excites - other areas: excite or inhibit depending
32
Effect of CNS control
- Can produce rapid increase in BP - double within 5-10 seconds - stimulate vasoconstrictor area - stimulate increase in cardiac activity - inhibit parasympathetic Vargas signals to heart
33
If MAP drops...what is CNS response
- constriction of most arterioles - increase SVR -> increase MAP - strong constriction of veins and larger arteries - move volume -> more preload -> more SV -> increase MAP - increase cardiac performance - increase HR (major effect) -> more CO -> increase MAP - increase contractility -> up SV -> up MAP (curve up and left)
34
Barroreceptors
- Stretch receptors in large arteries of thorax and neck - aortic and carotid bodies are big areas - Carotid: Hering nerve to glossopharyngeal nerve to sensory area - Aortic: vagus nerve to sensory area of vasomotor center - help maintain more constant MAP - If removed....MAP is all over the place - CAN normalize to if pressure changes and remains at new level - takes 1-2 days / no matter which way pressure changes - may mediate changes of tone to kidneys
35
Carotid barroreceptors
- In play more often - responds to lowest of 50 - 60 mmHg - then stretch happens
36
Aortic barroreceptors
- In play when MAP is a bit higher - 80 - 90 mmHg - receptors produce greater response when pressure is changing - not standing still....same with carotid receptors
37
Chemoreceptors
- sensitive to lack of O2 and excess CO2/H ions - In carotid bodies (2) - In aortic bodies (3) - excite nerve fibers through Herring's nerve and vagus nerve - If flow to receptor drops -> impulse increase -> excites vasomotor - kick in when pressure drops below 80 mmHg
38
CNS ischemic response
- Very powerful - direct response of vasomotor center to ischemia - increased levels of CO2 - can increase BP to 250 mmHg - will cut off flow to less important tissues - kicks in when BP below 60 mmHg - greatest level of stimulation at 15-20 mmHg
39
Atrial / Pulmonary stretch receptors
- low pressure receptors - minimize changes in atrial pressure due to sudden changes in blood volume (baroreceptors respond to stretch....these to flow) - bigger help in maintaining BP due to increase in volume
40
Atrial reflex and Kidney - A
- increase atrial stretch - reflex dilation of afferent arterioles in kidney - increase glomerular cap pressure - increase glomerular filtration - increase urine output - decrease CBV - decrease venous return - decrease CO - brings pressure down / happens slowly
41
Atrial reflex and Kidneys - B
- Increase atrial stretch - hypothalamus makes less ADH - decrease reabsorption of H2O in renal tubes - increased urine output - decrease CBV - decrease venous return - decrease CO - brings pressure down / happens slow...but little quicker than A
42
Bainbridge reflex
- increase atrial stretch -> increase in HR - via vagus nerve - 40-60% boost
43
Respiratory waves
- Change in arterial pressure 4-6 mmHg during each breath - Inspiration: pressure negative...vessels expand...decrease CO - Expiration: positive pressure...vessels constrict...increase CO - These can trigger vascular and atrial stretch receptors
44
Vasomotor waves
- slow oscillation of MAP of 10-40 mmHg - dynamic equilibrium - cycle is 7-10 seconds - oscillation due to baroreceptors / chemoreceptors

555- Physiology & Pathophysilogy (12 decks)

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