Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

PPoS > Intro to CVS (#2) > Flashcards

Intro to CVS (#2) Flashcards

(40 cards)

Start Studying
1
Q

List 3 ways cardiac output is regulated

A
  1. Preload
  2. Afterload
  3. ANS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is preload?

A

degree of stretch at end of diastole just before vent begin to pump

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

How does preload affect CO?

A
  • inc CVP stretches RV which responds by beating more forcefully + pumping more blood into the lungs
  • this inc pul vascular P + therefore P in LV which stretches + beats more forcefully
  • inc CO as pushing heart to work harder
  • also works with EDP (amount of blood in vent just before contraction) as more blood in vent make them more stretched
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How do venous P differ between R + L side of heart?

A
  • CVP on R side

- pul venous P on L side

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

What is afterload + what is it determined by?

A
  • load against which heart works to eject blood

- determined by aortic P

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

How does afterload affect CO?

A
  • inc afterload works against heart which caused dec ejection of blood
  • dec CO
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What causes inc afterload?

A
  • if mean BP v.high

- aortic stiffness - gets stiffer with age - causes inc P within it which inc afterload

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

How does ANS affect CO?

A
  • SNS inc HR, cardiac contractility (strength of contraction) through beta 1 receptors + SV which inc CO
  • PNS dec HR through muscarinic receptors which dec CO
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What happens to ESV at end of systole?

A
  • dec as heart pumped out more blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What does the Frank-Starling curve show?

A

relationship between SV + EDP

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

How does F-S curves affected by inc afterload + inc SNS activity?

A
  • inc afterload: inc EDP means less inc in SV so curve shifts down showing that for any given EDP, SV dec - less blood ejected
  • inc activity of cardiac symp nerve fibres: dec EDP means greater in SV so shifts curve up showing that for any given EDP, SV inc - more blood ejected
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is rel low arterial P gen by + why is it sufficient to drive blood through pul circ?

A
  • gen by RV (~ 16mmHg)

- bc pul vascular R v. low

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

What is Poiseuille’s law?

A

R prop to r to power of 4 of vessel

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

What is r + R of pul arteries + why?

A
  • shorter + so have larger radius which dec R

- also cap network supplying alveoli with blood forms v.dense mesh lowers R

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

What is sig of cap network surrounding alveoli?

A

massive SA for gas exchange of O2 + CO2 between blood + alveoli due to small diffusion distance between them

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

Why must R of lungs be low?

A
  • receiving same vol of blood as rest of body

- R must be low to accomm high CO from R side

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

What is pO2, Hb O2 binding site sat, O2 content of blood in systemic vascular system?

Study These Flashcards
A
  • pO2: ~ 100mmHg (higher due to gas exchange in lungs)
  • Hb O2 binding site sat: >/= 97%
  • O2 content: ~ 200ml/l
18
Q

What is pCO2 + CO2 content of blood in systemic vascular system?

Study These Flashcards
A
  • pCO2: ~ 40mmHg

- CO2 content: ~ 480ml/l (dec as its diffused into alveoli)

19
Q

What is P in aorta in systemic circ?

Study These Flashcards
A
  • 120 (diastolic)/80 (systolic)mmHg

- oscillating P

20
Q

How does diastolic + systolic P change with age?

Study These Flashcards
A
  • diastolic inc until middle age + then dec

- systolic P inc through life so chances of high BP is 50% by 50 which continues to inc

21
Q

What is blood velocity during systole + why?

Study These Flashcards
A
  • ~ 70cm/sec

- blood has lots of momentum as just been pumped out of L vent + quicker than velocity going into heart

22
Q

Describe passage of blood flow from heart to body

Study These Flashcards
A
  1. Blood pumped from LV into aorta
  2. Blood vessels branch out aorta to main organs: heart, brain, muscle, GIT, liver
  3. Blood then flows into microcirc
  4. Blood returned to RA
  5. Enters RV then pumped to lungs
  6. Blood returns to LA
23
Q

What is function of arterial system + its P?

Study These Flashcards
A
  • high P
  • regulates distribution of blood to diff regions of body mainly by small arteries + arterioles
  • does this by changing R through contraction + P of arteries in diff organs
24
Q

What is R of arterial system also known as + why?

Study These Flashcards
A
  • peripheral R
  • systemic peripheral R
  • systemic vascular R
  • TPR
  • biggest contributor to reg of BP +, vas R etc
25
How does liver get arterial supply + why does it need it?
- hepatic artery | - venous blood from GIT goes to liver but not getting enough O2
26
What is portal system and why is it needed?
- blood moves sequentially through 2 cap beds in series connected by a larger vessel - in liver, kidneys + part of brain - process ingested toxins from GIT before it gets to rest of body
27
What is org of microcirc?
large arteries ---> muscular arteries ---> arterioles ---> cap ---> venules ---> small veins ---> large veins
28
What is function of venous system?
collects blood from tissues + returns it to the heart
29
How much blood do the veins contain?
70% - acts as blood reservoir
30
What does contraction of veins cause?
redis blood to arteries, maintaining BP
31
What is arterial BP like?
- pulsatile | - osc between 80 + 120mmHg
32
How do you calc MABP?
diastolic + (systolic - diastolic)/3 or 1/3 pulse P
33
What is the pulse P?
diff between systolic + diastolic P
34
Why is MAP not av of sys + dia?
Heart spends more time in diastole so MABP closer to diastolic P bc its longer than systolic
35
What is incisura/notch due to?
closure of aortic valve
36
What is the P wave that occurs during diastole?
- aorta + arteries already full of blood so need to expand for blood to eject from heart - causes P wave where blood that's entered pushes against blood already there - propagated v. fast along aorta into large arteries which expand so can accept more blood
37
What causes a large pulse P?
large arteries bring blood to vas beds
38
Where is 75% of ejection fraction stored?
- transiently in aorta + large arteries where energy stored in elastic walls - already blood in aorta so expands to take on extra blood entering
39
What causes inc P in aorta?
- vent pump distends aorta | - aortic valve shuts at end of so blood can only go forwards
40
What happens to 25% of blood in aorta?
pushed forward out of other end of aorta into small arteries + rest of body in stuttering motion with each heartbeat

PPoS (11 decks)

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