When was the first Blood Transfusion?

The first successful blood transfusion on record was performed in 1665 by Richard Lower. Using quills and silver tubes, he transferred the blood from the artery of one dog to the vein of another. Two years later, he transfused a man with the blood of a lamb. He gave a demonstration of this before the Royal Society in London and the incident is recorded in the diary of Samuel Pepys.

Richard Lower was able to perform these transfusions thanks to William Harvey who, in 1628, announced his theory of the circulation of the blood. Before Harvey, people had always realized that blood was vital to life, but they didn't know how it circulated in the body.

A vital development in blood transfusion came in 1900, when Karl Landsteiner demonstrated the different blood groups in human beings. After that, people were transfused with blood of their own group whenever possible.

Nowadays, blood transfusion saves many lives. People can be treated for shock by pumping plasma (the fluid part of the blood) into them. Large reserves of blood are necessary for open-heart operations, sometimes as much as 20 pints a patient.

Why do we Turn White When Frightened?

We turn white when we are frightened because the blood in our cheeks is diverted to do a more urgent job. At the same time our hearts begin to beat much faster, and we breathe more quickly.

When we sit still, our hearts beat at about 70 to 80 times a minute, pumping the blood through our bodies. The blood carries nourishment from food, and oxygen from the air we breathe, both of which are vitally necessary for the body to function.

If we take violent exercise, our muscles need to work much harder and faster than when we are sitting or walking. They therefore need extra nourishment and oxygen. The nerves carry the message to that part of the brain called the hypothalamus, the center of an automatic nervous system in control of internal bodily functions such as the pumping of the heart, breathing and digestion.

Impulses from the hypothalamus travel down the spinal cord and excite other nerve cells - "sympathetic" neurons - which end in the center or medulla of the adrenal glands just above the kidneys. These glands release the hormone adrenalin into the bloodstream which causes the heart to beat faster and more efficiently, dilates air passages in the lungs and the blood vessels that supply the muscles, and increases the concentration of energy-giving glucose in the blood.

In fact, when we are frightened, exactly the same physical changes take place and our bodies are immediately and efficiently prepared for the violent exercise of flight or fight without any voluntary effort on our part.