Circulation aids

Question 1

What are circulation aids?

Answer 1

• Artificial blood
• Artificial hearts and heart valves
• Stents

Question 2

What is artificial blood?

Answer 2

It is a blood substitute, which is used to replace the lost volume of blood.

Question 3

How can artificial blood keep you alive in an emergency?

Answer 3

When you loose a lot of blood, the heart can still pump the remaining red blood cells around to get oxygen to your organs, as long as the volume of blood can be topped up (it can keep you alive even if 2/3 of your red blood cells are lost).

Question 4

Is artificial blood safe?

Answer 4

It’s safe as long as no air bubbles get into the blood.

Question 5

When will a patient need a blood transfusion?

Answer 5

If the patient does not have enough time to produce new red blood cells.

Question 6

What are artificial hearts?

Answer 6

Mechanical devices that are put into a person to pump blood if their own heart fails.

Question 7

What are artificial hearts usually used as?

Answer 7

A temporary fix, to keep a person alive until a donor heard Is found.

Question 8

Occasionally what are artificial hearts used as?

Answer 8

A permanent fix, reducing the need for a donor heart.

Question 9

What’s the main advantage of an artificial heart?

Answer 9

They’re not rejected by the body’s immune system.

Question 10

Why aren’t artificial hearts rejected by the body’s immune system?

Answer 10

Because they’re made from metals or plastics, so the body doesn’t recognise them as ‘foreign’ and attack in the same way as it does with living tissue.

Question 11

What are the disadvantages of artificial hearts?

Answer 11

• Surgery to fit them can lead to bleeding and infection.
• They don’t work as well as healthy natural hearts.
• Parts of the heart could wear out.
• The electrical motor could fail.
• Blood doesn’t flow through artificial hearts as smoothly, which can cause blood clots and lead to strokes, meaning the patient has to take drugs to thin their blood (which can cause problems with bleeding If hurt in an accident).

Question 12

If only heart valves are defective, what can they be replaced with?

Answer 12

Mechanical valves.

Question 13

What happens when we replace a valve with a mechanical one?

Answer 13

Replacing a valve is much less drastic, although major surgery is till required to fit them and problems still can occur with blood clotting.

Question 14

What are stents?

Answer 14

They are tubes that are inserted inside arteries.

Question 15

What do stents do?

Answer 15

They keep arteries open, making sure blood can pass through to the heart muscles (keeping a persons heart beating, and them alive).

Question 16

What disease may require the aid of stents?

Answer 16

Coronary heart disease, as they lower the risk of heart attack in that person with this disease.

Question 17

What is coronary heart disease?

Answer 17

When the arteries that supply the blood to the muscle of the heart get blocked by fatty deposits, causing arteries to become narrow restricting blood flow, which can result in a heart attack.

Question 18

What can happen to an artery with stents over time?

Answer 18

They can irritate the artery making scar tissue grow, causing the artery to narrow again (the patient also has to take drugs to stop blood clotting in the stent).