It can happen from time to time that a doctor will tell you that you will have to go for a blood test. There can be a lot of reasons for this and many illnesses or problems with your organs like your liver and your heart can be picked up by having your blood tested.
Specifically, blood tests can help doctors: Evaluate how well organs—such as the kidneys, liver, thyroid, and heart—are working. Diagnose diseases and conditions such as cancer, HIV/AIDS, diabetes, anemia (uh-NEE-me-eh), and coronary heart disease. Find out whether you have risk factors for heart disease.
You can read more about blood tests on http://www.lancet.co.za/wp-content/uploads/2015/07/WHY-DO-YOU-NEED-BLOOD-TESTS.pdf
It can be a scary idea to have to go for a blood test, but if you know what to expect, it can make it a bit easier.
The person who will be taking your blood is called a 'phlebotonist', but in most countries a nurse or doctor can or will also do the procedure.
In some instances, the doctor will order a 'fasting blood test'. This means that you may not eat 10 hours before the blood test. One of the reasons why this will be done is to test the glucose in your blood and see if you maybe have diabetes.
The time you have to fast before you can go for the test, will be determined by the type of test you need to go for, but your doctor will inform you of how long and if you will have to fast.
There will also be different amounts of blood that will be taken, depending on what the doctor will have to test for. The more tests that they need to do, the more blood they will take. The laboratory will need enough blood in order to do the tests successfully.
When you are done with the test, it is always a good idea to drink something like a juice. Some people feel a bit faint after a blood test and the juice will help to restore your blood sugar. Also sit still for a few minutes after the test, especially if they have taken a lot of blood. It can happen that if you get up too quickly, you will faint.
The nurse or doctor will look at the veins on the inside of your arm where your elbow is, or on the back of your hand and decide which one will be the best to use to get the right amount of blood in the shortest time.
The nurse will tie a tight band around your upper arm to make sure that the vein fills with blood and it is easy to get the blood. It can happen that they do not get enough blood with the first try, but do not stress about that. Most nurses have been doing it for such a long time or so many times that they get it right the first time.
They will clean the area where the vein is and if you are very scared of needles, you can ask for a numbing ointment or spray.
A needle will be inserted into the vein to be able to draw the blood. You may feel a pinch, but it is not so sore. It is one prick and it is over. So just hold on, it will be over before you know it.
Do not tense up or scream. This will make the job of the nurse more difficult. The calmer you stay, the quicker it will all be over.
It is a better idea not to look when they insert the needle, but if you feel you can handle it, you may have a look why they do it.
Once the right amount of blood has been drawn, they will take out the needle and hold a piece of gauze over the place where the needle was. Apply a little pressure and the blood flow will stop quickly.