Venous Return And Starlings Law

Question 1

What is venous return

Answer 1

Venous return is the return of blood to the right side of the heart via the vena cava

Question 2

What is starling law

Answer 2

During exercise, more blood is being pumped back to the heart (venous return) this means that more blood needs to be pumped back out of the heart, increasing stroke volume. This is starlings law

Question 3

What are the venous return mechanisms

Answer 3

Skeletal pump

Respiratory pump

Pocket valves

Gravity

Smooth muscle in the walls of veins

Question 4

What is the skeletal pump

Answer 4

When muscles contract and relax they shape. This change in shape causes the muscles to press on nearby veins and squeeze the blood towards the heart

Question 5

What is the respiratory pump

Answer 5

When muscles contract and relax during breathing. Pressure changes in the chest and abdominals. This change in pressure causes a press on nearby veins forcing blood back to the heart

Question 6

What is pocket valves

Answer 6

Blood in the veins must only flow in one direction. Valves ensure this. As blood flows through it the valves close, preventing back flow

Question 7

Systolic blood pressure

Answer 7

The pressure in the blood vessels when the ventricles are contracting

Question 8

Diastolic blood pressure

Answer 8

The pressure of the blood vessels when the ventricles are relaxing

Question 9

What is the equation the links to the increase and decrease of venous return

Answer 9

Venous pressure - right atrial pressure/ venous vascular resistance