Download Blood Test

Department of Pathology
Blood Test
What is a blood test?
Blood tests help the doctor with your diagnosis, in monitoring your treatment or reviewing the
levels of some medications.
Are there any complications from blood taking?
Sometimes a bruise develops where the needle was inserted. This is much less likely to
happen if you press over the site with cotton wool for several minutes with your arm straight (not
bent).
As with any wound, an infection may develop where the needle was inserted. Please consult
your GP if the wound site becomes red and/or inflamed.
Rarely, some people feel faint during a blood test. Tell the person doing the test if you feel faint
as you should lie down immediately to prevent fainting. It is helpful to let us know if you have
felt faint before when having a blood test.
Please note that young patients will be offered a gel that numbs the area of the blood test. This
requires a minimum of 30 minutes to work. Redness around the area of the gel is not
uncommon, swelling and itching may also occur.
How is a blood test carried out?
In the Pathology Department, before you are called in for your test it would help us if you
remove your coat/jacket and roll up your sleeve.
Blood tests are taken from a vein, usually on the inside of the arm, near to the elbow. First a
fabric band (tourniquet) is tied around the upper arm to make the vein prominent. The tourniquet
will become tight, but this makes it much easier to take the blood.
A needle is put into the vein – you might feel a slight scratch. The needle will be attached either
to a blood test bottle, or to a syringe. When the necessary amount of blood has been taken, the
needle is removed, the tourniquet released and a little ball of cotton wool is held over the
wound. This should be pressed for 1 – 2 minutes before a dressing is applied.
If you need this information in another format or language 01536 492510
Further information about the Trust is available on the following websites:
KGH - www.kgh.nhs.uk | NHS Choices - www.nhs.uk
Ref: PI 452 September 2014
Review: June 2016
Contact Details
Pathology Department  01536 492694
Monday to Friday 09:00 am – 5:00 pm