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How is it performed? of Blood tests

Usually the sample is taken out of a blood vessel in your arm. The arm is a convenient part of the body to use, as it can be easily uncovered. The usual place for a sample is the inside of the elbow or wrist, where the veins are relatively close to the surface.

Blood samples from children are usually taken from the back of the hand. The child’s hand will be anaesthetised with a special cream before the sample is taken.

A tight band is usually put around your upper arm. This squeezes the arm, temporarily slowing the flow of blood out of the arm, and causing the vein to swell with blood.

Before taking the sample, the doctor or nurse may wipe the area with a cotton wool pad containing antiseptic, to prevent infections. 

A needle attached to a syringe, or  to a special blood collecting container, is pushed into the vein and the syringe is used to draw out a sample of your blood. You will just feel a tiny pricking feeling as the needle goes in and it should not be painful at all. If you don’t like needles and injections, tell the person who is taking the sample, so that they can make you more comfortable. If you feel faint, you should lie down.

Sometimes only a tiny sample of blood is needed, so your finger can be pricked and a few drops of blood squeezed out.

When the sample has been taken, a plaster (sticky bandage) may be put over the tiny break in the skin.

For certain types of blood tests you may be asked not to eat for a while before the test.

The sample of blood is put into a bottle and labelled with your name. It is then sent to a laboratory where it is examined under a microscope or tested with chemicals, depending on what is being checked. The results get sent back to the hospital or to your GP and you will be told when and how you will be given them.