Systems: Integration

Front 1

What is the venous pressure that results in filling of the heart in diastole, and is largely dependent on venous return?

Back 1

Preload

Front 2

What is preload?

Back 2

Venous (return) pressure that is responsible for filling.

Central venous pressure

Front 3

What is afterload?

Back 3

The pressure the heart must work against to eject blood.
Aortic pressure
Peripheral resistance

Front 4

What is cardiac output?

Back 4

volume ejected/time

Front 5

What is stroke volume?

Back 5

volume ejected/beat
EDV - ESV = SV
(filled volume - volume after ejection)

Front 6

What comprises the central venous pool?

Back 6

Great veins in the thorax and the right atrium

Front 7

What factors determine cardiac output?

Back 7

Heart rate
Contractility
Preload
Afterload

Front 8

What is the name of the resistance felt by blood as it moves from the arterial side to the venous side?

Back 8

Total Peripheral Resistance

Front 9

What vessels are the major regulators of peripheral resistance?

Back 9

Arterioles

Front 10

How are cardiac output, heart rate, and stroke volume related?

Back 10

CO = HR X SV
v/t = beat/t (x) v/beat

Front 11

What is inotropy?

Back 11

Something that changes the strength of muscular contraction

Front 12

What is the relationship of cardiac output, mean arterial pressure, and total peripheral resistance?

Back 12

MAP = CO X TRP

CO = MAP/TRP

Front 13

An increase in blood pressure will result in a decrease in the tone of VSMC. How?

Back 13

An increase in BP is sensed in the carotid sinus (CN IX afferent). The signal in modulated in the medulla, which will decrease the sympathetic to VSMC. This will decrease tone and reduce BP via decreased resistance.

Front 14

What factors make up the extrinsic regulation of the heart rate?

Back 14

ANS
Humoral factors

Front 15

Preload and afterload will effect which component of stroke volume?

Back 15

ESV

Front 16

What is the efferent limb of the baroreceptors?

Back 16

ANS

Front 17

What is the effect of gravity on the vessels below the heart?

Back 17

Increases the pressure

Front 18

What is the effect of gravity on the vessels above the heart?

Back 18

Decreases the pressure

Front 19

How does prolonged standing effect capillary hydrostatic pressure?

Back 19

Increase

Front 20

How does prolonged standing effect interstitial fluid pressure?

Back 20

Increases

Front 21

How does prolonged standing effect lymph flow?

Back 21

Increases

Front 22

How does prolonged standing effect baroreceptor firing? What does this cause?

Back 22

Decreases
Increase SNS response

Front 23

How is heart rate effected moving from supine to upright?

Back 23

Increases

Front 24

How is cardiac output effected moving from supine to upright?

Back 24

Decreases

Front 25

How is total peripheral resistance effected by moving from supine to upright?

Back 25

Increases

Front 26

How is the central blood pool effected when moving from supine to upright?

Back 26

Decreases

Front 27

How do baroreceptor reflexes compensate for a drop in BP when moving from supine to upright?

Back 27

Increase HR
Increase TPR

Front 28

How does the renin-angiotensin system response when moving from supine to upright?

Back 28

Increase in renin
Increase in Aldosterone

Front 29

What is the function of renin?

Back 29

Cleaves angiotensinogen into angiotensin I

Front 30

What is the function of aldosterone?

Back 30

Reduce the excretion of sodium and water
Increase BP

Front 31

What is the antagonist to aldosterone?

Back 31

ANP
atrial natriuretic peptide

Front 32

How does the brain respond to moving from supine to upright?

Back 32

Cerebral dilation and increased oxygen extraction via autoregulation to maintain constant oxygen consumption.

Front 33

Will a hemorrhage increase or decrease the rate of baroreceptor activity? Why?

Back 33

Decrease
BR increase activity in response to increased BP

Front 34

A decrease in baroreceptor activity will activate which efferent limb? To which organs?

Back 34

SNS to the heart
SNS to the vessels

Front 35

How does increased SNS effect the heart?

Back 35

Increase HR and contractility

Front 36

How does increased SNS effect the vessels?

Back 36

Increased vasoconstriction

Front 37

How will the renin-angiotensin system respond to hemorrhage?

Back 37

Increased renin
Increased angiotensin II
Increased aldosterone

Front 38

What is the immediate response to a hemorrhage (general)?

Back 38

Reflex compensation

Front 39

What is the most prolonged response to a hemorrhage?

Back 39

Decreased renal excretion
Increased ingestion of salt/water

Front 40

How much can the renin-angiotensin system compensate after a severe hemorrhage?

Back 40

Can return half the arterial pressure

Front 41

The carotid sinus reflex which will increase SNS will constrict all vessels, except where?

Back 41

Heart
Brain

Front 42

What is the threshold to elicit CNS ischemic response and activation of SNS?

Back 42

BP below 60 mmHg

Front 43

What cells release oxygen radicals during prolonged ischemia?

Back 43

Immune cells

Front 44

What is the major disturbance for hypotension or hemorrhage?

Back 44

reduced arterial blood pressure leading to reduced cardiac output

Front 45

What is the effect of exercise on cardiac output?

Back 45

increased

Front 46

What is the status of total peripheral resistance during exercise?

Back 46

reduced

Front 47

Exercise increases SNS to what organs?

Back 47

Muscle vasculature (dilation)
Non-exercising arterioles (constriction)

Front 48

Why is there a cutaneous vasodilation in response to exercise?

Back 48

increasing body temperature

Front 49

What is the purpose of decreasing peripheral resistance during exercise?

Back 49

Reduce MAP since we have increased CO
Direct CO to exercising muscles

Front 50

What are the vasodilators responsible for local control in exercise?

Back 50

Adenosine
Potassium
Lactate

Front 51

How many fold increase can oxygen consumption experience in the muscles during exercise?

Back 51

100 fold

Front 52

How is blood flow to the brain altered during exercise?

Back 52

it is not

Front 53

How is blood flow to the skin altered during exercise?

Back 53

it is not

Front 54

How is blood flow to the heart altered during exercise?

Back 54

increased (x4)

Front 55

What can cause hypertrophy in the heart?

Back 55

obstruction to flow

Front 56

What are three mechanisms of heart failure due to cardiac muscles?

Back 56

systolic dysfunction (poor contraction)
diastolic dysfunction (poor filling)
Hypertrophy

Front 57

What is the effect of systolic dysfunction on ESV and EDV?

Back 57

Decreased SV
Increased DV
Fluid retention

Front 58

Why does EDV increase with systolic dysfunction (heart failure)?

Back 58

to try to increase CO

Front 59

Why does end diastolic volume pressure rise with progressive heart failure?

Back 59

Increased fluid retention leading to stretching of the ventricle and reducing the ability to contract.

Front 60

A decreased EDV in heart disease signifies what?

Back 60

Diastolic dysfunction
Reduction in ventricular compliance
Hypertrophy

Front 61

How is stroke volume effected in diastolic dysfunction?

Back 61

reduced

Front 62

Why does CHF lead to edema?

Back 62

retain Na/water to maintain blood pressure since you have decreased CO.

This increase in pressure causes fluid to be lost into the interstitial space.

Front 63

What drug is used to increase cardiac contractility?

Back 63

digitalis

Front 64

What drug can be given to heart failure patients to reduce edema?

Back 64

diuretics

Front 65

What drug can be given to heart failure patients to increase vasodilation and lower BP?

Back 65

ACE inhibitors