Cardiac Output

Question 1

What is the quantity of blood pumped into the aorta each minute by the heart as well as the blood that flows through the circulation?

Answer 1

Cardiac Output

Question 2

What is the sum of all blood that flows to the tissues of the body?

Answer 2

Cardiac Output

Question 3

CO = ___ x ___

Answer 3

SV x HR

Question 4

For CO, the pre-load is the ____ diastolic volume

Answer 4

EDV

Question 5

For CO, the after-load is the ____

Answer 5

MAP

Question 6

Venous Return (VR) is the quantity of blood flowing from the veins into the _______ each minute

Answer 6

right atrium

Question 7

What 2 things must equal each other (except for a few heartbeats at time when blood is temporarily stored in or removed from heart and lungs)?

Answer 7

CO and VR

Question 8

What factors directly affect CO?

Answer 8

1. Metabolism
2. Physical Activity
3. Age
4. Body Size (sex differences)

Question 9

CO ____ in proportion to body surface area (BSA)

Answer 9

increases

Question 10

Cardiac Index (CI) is the CO per ____ ___ of BSA

Answer 10

square meter

Question 11

Normal human weighs 70kg with BSA 1.7m^2, which means their Cardiac Index is equal to ____L/min/m^2 of BSA

Answer 11

3

Question 12

Cardiac Index ____ over the lifespan

Answer 12

steadily decreases

Question 13

CO is regulated throughout life almost directly in proportion to overall _____

Answer 13

metabolic activity

Question 14

CO is controlled mainly by peripheral factors that determine ____ return

Answer 14

venous

Question 15

____ blood flow stretches the walls of the heart chambers, cardiac muscle ___ with increased force, resulting in the ____ of the extra blood

Answer 15

increased
contracts
emptying

Question 16

Stretch of the Sinus Node in the wall of the ___ atrium has a direct effect on the rhythmicity of the node to increase the HR as much as ___-___%

Answer 16

right

10-15%

Question 17

Bainbridge Reflex (atrial reflex): an ___ in HR due to an ___ in central venous pressure signals the cardiovascular regulation center of brain to signal sympathetic and vagi nerves to ___ HR (by __%)

Answer 17

increase
increase
increase
15%

Question 18

Which organ/tissues have the most cardiac output?

Answer 18

splanchnic (liver area)

Question 19

CO is determined by the sum of all the factors that control

Answer 19

local blood flow

Question 20

The sum of local blood flows form what?

Answer 20

venous return

Question 21

The heart automatically pumps returning blood back into the ____ to flow through the system again

Answer 21

arteries

Question 22

Blood flow increases mainly in proportion to each tissue’s

Answer 22

metabolism

Question 23

Ohm’s Law: ___ = MAP/TPR

Answer 23

cardiac output

Question 24

Normal Cardiac Output Curve shows a normal ___ in CO with ___ in right atrial pressure

Answer 24

increase; increase

Question 25

Which CO Curve shows a plateau of approx. 13 L/min (2.5x normal CO?)

Answer 25

Normal CO Curve

Question 26

Without any stimulation, this CO curve can pump a venous return up to about 2.5x normal before the heart becomes limiting factor

Answer 26

Normal CO curve

Question 27

The Hyperreflexive Heart is caused by ___ stimulation, which increases ___ and ___

Answer 27

nervous; HR; contractility

Question 28

____ stimulation and ____ inhibition causes Hyperreflexive Heart CO Curves

Answer 28

sympathetic stim

parasympathetic inhib

Question 29

_____ can occur as result of a hyperreflexive heart, which means elite athletes like marathon runners can increase their heart mass by __-__%

Answer 29

Hypertrophy; 50-75%

Question 30

When nervous stimuli and hypertrophy are COMBINED in marathon runners, the total effect can allow the heart to pump as much as __-__ L/min or 2.5x the level a normal person can achieve

Answer 30

30-40

Question 31

Hypoeffective Heart has ___ arterial pressure against which the heart has to pump, leading to severe ___

Answer 31

increased; hypertension

Question 32

Hypoeffective Heart has ___ of nervous excitation

Answer 32

inhibition

Question 33

What pathological facts can cause a Hypoeffective Heart?

Answer 33

Abnormal Rhythms
Abnormal Rate of Heartbeats
Coronary Artery Blockage (MI)
Valvular Heart Disease
Congenital Heart Disease
Myocarditis (inflammation of heart muscle)
Cardiac Hypoxia

Question 34

Measuring CO by using an instrument is determined by a electromagnetic or US flowmeter by measuring the

Answer 34

pulsatile output

Question 35

Under MOST normal unstressed conditions, CO is controlled MAINLY by ____ factors that determine ____ return

Answer 35

peripheral; venous

Question 36

What determines VR? (3)

1. ___ ___ pressure
2. ____ ____ filling pressure
3. ____ to VR

Answer 36

1. PRA - Right Atrial Pressure
   (normal: 0mmHg)
2. Mean Systemic Filling Pressure (Psf)
   (normal: 7mmHg)
3. Resistance to Venous Return (RVR)
   (normal: 1.4mmHg/L/min)

Question 37

If VR = 5 L/min, what is CO?

Answer 37

CO = VR, so CO should also be 5L/min