Question 1

is fever an indicator of an increase in cardiac output?

Accepted Answer

No but it is a cause: Fevers cause your heart rate to increase. Cardiac output is determined by heart rate x stroke volume. So if you increase hr you increase cardiac out put.

Question 2

how do beta-clockers increase cardiac output?

Accepted Answer

They don't: Beta blockers do not increase cardiac output.  If anything, they reduce cardiac output by reducing heart rate and the strength of contraction (contractility).

Question 3

can you tell me if cardiac output increases / decreases?

Accepted Answer

Both: In a normal person, cardiac output increase with exertion then returns to a normal or resting level.  With a malfunctioning heart, cardiac output is frequently considered low or subnormal.

Question 4

if cardiac output of 4 l/min is exercised maximally, and cardiac output increases to 8 l/min. what is the cardiac reserve?

Accepted Answer

Cardiac reserve: It is the difference between resting and maximum cardiac output, so 4 L/min

Question 5

will acetylcholine raise cardiac output?

Accepted Answer

Not expected to: Acetylcholine (parasympathetic nervous system) should have the opposite effect from Epinephrine (sympathetic nervous system) and therefore should slow the heart rate and decrease the force of contraction of the heart. Both effects would tend to lower the cardiac output (stroke volume times the heart rate). The stroke volume is the amount of blood ejected with each heart beat.

Question 6

will epinephrine increase cardiac output?

Accepted Answer

Yes: It makes the heart contract more forcefully and makes it beat faster. Both effects will increase the cardiac output.

Question 7

how does the heart increase cardiac output?

Accepted Answer

Two ways: Either by pumping out more blood with each beat (by squeezing harder) or by beating faster. The output is the heart rate times the stroke volume. (the amount of blood pumped out with each beat).

Question 8

how do beta-blockers increase cardiac output?

Accepted Answer

They don't: Cardiac output is the product of heart rate and stroke volume. Beta blockers decrease heart rate and the strength of contraction (contractility). Thus, beta blockers would not be expected to increase cardiac output.

Question 9

how does hypertension increase cardiac output?

Accepted Answer

It doesn't: In a physiologic model, increased blood pressure or "hypertension" or increased "afterload" tends to decrease cardiac output. In a complete animal or human model, there are various reflexes that work to maintain cardiac output in the face of increased afterload but they shouldn't cause an increase in cardiac output relative to the baseline.

Question 10

why is there increased cardiac output in anemia?

Accepted Answer

Contracts harder: The cardiac output is the stroke volume times the heart rate. So the heart has to contract harder and/or faster. Typically, in severe anemia, an echocardiogram would show the heart contractng harder than normal.

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Doctor answers about:

Will a fever increase cardiac output

A member asked:

Is fever an indicator of an increase in cardiac output?

A member asked:

How do beta-clockers increase cardiac output?

A member asked:

Can you tell me if cardiac output increases / decreases?

A member asked:

If cardiac output of 4 l/min is exercised maximally, and cardiac output increases to 8 l/min. what is the cardiac reserve?

A member asked:

Will acetylcholine raise cardiac output?

A member asked:

Will epinephrine increase cardiac output?

A member asked:

How does the heart increase cardiac output?

A member asked:

How do beta-blockers increase cardiac output?

A member asked:

How does hypertension increase cardiac output?

A member asked:

Why is there increased cardiac output in anemia?

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