Brainscape's Knowledge GenomeTM

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


See full index

PHSL 232 > L25 (pathophysiology) > Flashcards

L25 (pathophysiology) Flashcards

1
Q

does the heart spend more time in diastole or systole

at rest?
during exercise?
what effect does this have on MAP

A

at rest diastole however during exercise it is systole

this means that MAP is closer to the diastolic pressure than the systolic pressure

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

what is the equation for MAP

A

DAP + 1/3(SAP-DAP)

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

define hypertension

A

high arterial blood pressure at rest

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

what is the range for prehypertension/elevated blood pressure

A

SAP = 120-129mmHg

DAP < 80

therefore it is when only SAP has increased

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

what is the range for stage 1 and stage 2 hypertension

A

stage 1

  • SAP = 130-139
  • DAP = 80-89

stage 2

  • SAP >140
  • DAP > 90

for both stage 1 and 2 you only need to have in increase in diastolic or systolic pressures

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

what is the prevalence of hypertension in NZ

and why could this be underestimated

A

21.4% of NZders or 1:5
this means 1 million people in NZ have hypertension

this could be underestimated because it is only including people that are taking medication to reduce their blood pressure and not everyone knows that they have it and if they have it it doesn’t mean that they ae on medication for it

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

what is hypertensions relationship with age and gender

A

the prevalence increases with age

there is no difference between gender

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

what is the main cause of hypertension

A

TPR

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

what determins TPR

A

Vessels in series and parallel determine TPR

resistance cant cause resistance

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

where is the largest pressure drop

A

Largest pressure drop
in small arteries and arterioles
(resistance vessels)

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

what are the physical factors that cause hypertension

A

Arterial blood volume increase

Arterial compliance decrease

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

how is arterial blood volume regulated

A

by the kidney in the long term

osmoreceptors detect increased osmotic pressure causing the release of ADH from posterior pituitary which acts on the blood vessels causing vasoconstriction-> increased BP

baroreceptors in the aortic arch and carotid sinus detect blood pressure, this causes ADH to be released from the posterior petuitory which acts on the kidney to increase water reabsorption which leads to increased blood volume and pressure

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

what is the difference between Arteriosclerosis and Atherosclerosis

A

aRterIosclerosis = disease of the media and alters the stiffness of the vessels (media thickening)

atherOsclerosis = disease of the intam which alters the conduct (blockage)

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

define aRterIosclerosis

A

disease of the media and alters the stiffness of the vessels

Media thickening in large or resistance arteries
Increasing stiffness of the arteries

happens because of hypertension (ageing)

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

define atherOsclerosis

A

disease of the intam which alters the conduct

Changes of the intima causing blockage of the arteries (plaque formation)

caused by Coronary and peripheral artery disease

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

describe the relationship between arterial compliance and age

A

older people have less arterial compliance

when pressure increases in the vessels that do not expand as much

Less compliant vessels with age - reduced arterial compliance = hypertension

17
Q

whoops

A

whoops

18
Q

why does hypertension increase with age

A

as you age the vessel wall has less and less elastin and more collagen

the collagen that you get with ageing is different to the normal collagen in the wall as this collagen is stiffer as it makes more crosslinks

collagen is 1000x stiffer than elestin therefore with the increase in collagen and the decrease in elestin you REALLY increase the stiffness of the arterial wall increasing peripheral resistance therefore causing hypertension

19
Q

describe collagen as we age

A

the collagen that you get with ageing is different to the normal collagen in the wall as this collagen is stiffer as it makes more crosslinks

collagen is 1000x stiffer than elestin therefore with the increase in collagen and the decrease in elestin you REALLY increase the stiffness of the arterial wall causing increase in resistance

20
Q

normal blood pressure is 120/80

Elevation in peripheral vascular resistance
(due to decrease in arterial compliance) can increase the systolic and diastolic pressures by how much

A

DAP + 10-40 mmHg

SAP + 50-100 mmHg

21
Q

what are flow waves

A

they are generated by the heart in systole when it pumps out blood

flow waves are the flow of blood

22
Q

In systole, flow waves are generated by the heart

what is their relationship with the compliance of the aorta

A

Storage of stroke volume in conduit vessels – distensibility of aorta

In diastole, recoil of aorta maintains capillary flow

23
Q

describe flow waves in the aorta vs the capillaries

why is this

A

Pulsatile flow into the aorta, but continuous/constant flow through the capillaries

Compliance of the aorta is essential to dampen the pulsatile flow wave of the heart

24
Q

in hypertension the systolic pressure increases more than the diastolic pressure, why is this

A

The aorta is the major contributor for dampening the pulsatility of the heart

With hypertension the aorta becomes stiffer therefore there is not storage of SV during systole. once the valve closes then there is no flow through the aorta as there is little elastic recoil

Therefore the aorta becomes less flexible with age which increases and decrease the pressure therefore creating pulsatile flow

25
Q

what is hypertensions effect on gas exchange in the capillaries

A

it causes the capillary flow to become pulsatile which is bad for exchange (decreases it)

this is because the aorta is not acting as an elastic reservoir

26
Q

During systemic hypertension, the compliance of the aorta:

A. decreases, which decreases the pulsatility of blood flow through the capillaries.

B. decreases, which increases the pulsatility of blood flow through the
capillaries.

C. increases, which decreases the pulsatility of blood flow through the
capillaries.

D. increases, which increases the pulsatility of blood flow through the
capillaries.

A

B

27
Q

what is a pulse wave

A

they are generated by the heart, independent of blood flow (not a flow wave)

this is the contraction moving through the wall of the vessel

28
Q

what are the velocity values of a flow wave compared to a pulse wave

A

flow wave = 0-20cm/s

pulse wave 2-12m/s

note PW is in m/s and flow is cm/s

29
Q

in the aorta how many x faster is the pulse wave compared to the flow

A

100x

30
Q

what happens when a pulse wave hits a bifurcation

A

a reflection wave is formed

31
Q

describe the forward and reflected wave

A

these are both pulse waves

when the forward wave his a bifurcation it forms a reflected wave which moves in the opposite direction

the reflected wave is always slightly behind the forward wave

32
Q

what is the observed wave

A

it is the combonation of the forward and the reflected wave

this is what you measure when you are taking blood pressure

33
Q

Proximal vessels compliant whereas the Distal vessels are stiffer

what does this mean in terms of the pulse waves

A

Pulse wave travels faster in distal than proximal vessels

Aorta 3-5 m/s
Radial artery 5-12 m/s

this is because the stiffer the vessel the faster the wave

34
Q

what does the diffeent stiffness of the vessels mean fo the observed blood pressure

A

Distal vessels are stiffer (faster pulse wave) they have larger contribution of reflections compared to proximal vessels meaning that the pressure in the distal arteries will be slightly higher

this is a minor difference (5-10mmHg) compared to the classification of hypertension which has ranges of 20mmHg (therefore you don’t have to worry about it that much)

35
Q

describe pulse wave velocity as we age

A

Reduced compliance of conduit arteries increases pulse wave velocity

higher contribution of reflected wave

The observed wave will be higher because of stiff arteries which they will contribute more to reflection

36
Q

who does the reflected wave being faster increase the observed wave (and therefore BP)

A

the more the waves overlap the more they add together

when the wave is faster it adds together with the forward wave more

37
Q

in compliant vessels what happens when the reflected wave is reflected back to the heart

A

normally when the reflected wave reaches the heart the valves are closed therefore it contributes to

when the reflected wave comes back in increases the BP slightly and enters the coronary circulation

38
Q

in hypertension what happens when the reflected wave is reflected back to the heart

A

As the arteries become more stiff there is a greater observed wave and pulsatility of the capillaries. This means that the reflected wave will be reflected back before the valves close which will increase afterload.

the coronary blood supply is affected in this as well

39
Q

The pulse wave velocity of the aorta decreases with older age

BECAUSE

at older age remodeling of the arterial wall results in a faster reflected pulse wave

A

the first statement should say increases

therefore the first statment is incorrect and the second statment is correct

PHSL 232 (30 decks)

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