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Flashcards in Venous Return Deck (16)
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1

Venous return refers to the amount of blood and blood flow

returned back to the heart from veins

2

Therefore, since CO is 5 L/min, venous return

also equals 5 L/min.

3

Arthur Guyton correlated the relationship between 2 things to control venous return.

mean systemic filling pressure (MSFP) and right atrial pressure (RAP)

4

MSFP is approx
RAP is approx
CO is appr

7 mm Hg
0 mmHg
5L/min

5

As CO (or venous return) increases, CVP

Decreases and more blood is pumped from veins to the right atrium.

6

Consequently, increases in MSFP or decreases in RAP lead to

increased venous return

7

Venous return increases as the pressure difference
between

RAP and MSFP increases.

8

If RAP (or CVP) is low and MSFP high, then there will be a

maximum change in
pressure and a maximum venous return of blood to the right
heart.

9

On the other hand, if RAP increases, but there is no
change in MSFP, then there will be a small difference between the two variables and venous return will

decrease

10

Anything that causes volume retention

increases MSFP.

11

Alternatively, situations that decrease blood volume, such as hemorrhage and dehydration,

decrease MSFP and venous return.

12

Peripheral veins have _____ valves that.

one-way direct flow of blood away from the limbs and toward the heart

13

Muscle contraction causes venous_________, and muscle relaxation causes venous ______

compression;decompression.

14

The alternative contraction and relaxation patterns cause blood to be pumped

back to the heart, and unidirectional valves prevent blood from flowing back toward the limbs, enhancing venous return

15

Respiratory activity influences venous return to the heart by

augmenting the pressure difference between abdominal veins and the right atrium.

16

Inspiration and intrathoracic pressure

decrease in intrathoracic pressure.