A lumbar puncture (spinal tap) is done to test the fluid (cerebrospinal fluid or CSF) around the
spinal cord and brain. By placing a thin hollow needle between the bones of the lower back, a
small sample of fluid can be taken for testing.
There are many diagnoses that can be made from a lumbar puncture. They include:
You will be asked to lie on your side with your knees drawn up and your head bent down. You
must remain as still as you can during the procedure. You will receive a shot to numb the
puncture site. You will feel pressure as the doctor inserts the needle. Let the doctor or nurse
know if you feel any pain. Breathe deeply and slowly. The CSF will come out through the
needle drop by drop. Once enough fluid has been taken for testing, the needle will be pulled out.
A band-aid may be placed over the site. The entire test will last about 20 to 30 minutes. You
will need to lay flat for about 60 minutes.
As with any procedure, there are risks. Some of the risks include:
ξ Pain – Patients may feel a poke as the doctor inserts the needle into the back. Numbing
drugs are used to lessen the pain. Once the needle is in, the pain is often mild and goes
ξ Headache – This may occur after the test. It is often mild and goes away on its own. Let
your nurse know if your headache is severe.
ξ Bleeding – When the doctor inserts the needle, there is a risk of bleeding at the site. If
this happens, the bleeding is often minimal or stops on its own. Rarely, bleeding can
occur into the spinal cord.
Your health care team may have given you this information as part of your care. If so, please use it and call if you
have any questions. If this information was not given to you as part of your care, please check with your doctor. This
is not medical advice. This is not to be used for diagnosis or treatment of any medical condition. Because each
person’s health needs are different, you should talk with your doctor or others on your health care team when using
this information. If you have an emergency, please call 911. Copyright © 6/2015 University of Wisconsin Hospitals
and Clinics Authority. All rights reserved. Produced by the Department of Nursing. HF#6345