Lumber Puncture

What is a Lumbar Puncture?

A lumbar puncture is a special test used to look at the fluid that is in your spine. This fluid is called CSF or Cerebrospinal Fluid.

This clear fluid flows around your brain and your spine. It can give the doctor information about how your body is working and what they need to do to help you.

Your spine is made up of many small bones. If you make a fist and look at your knuckles, the bones in your knuckles look like the bones in your spine. Just like there are gaps between your knuckles there are also gaps between the bones in your spine. The CSF is found in the gap between the bones of your spine.

Why do I need to have a Lumbar Puncture?

You are having a lumbar puncture because the doctor needs to check your cerebrospinal fluid (CSF) to find out what is making you feel sick and how they can help you.

What happens when I have a Lumbar Puncture?

A porter will come to bring you to the special room to have the lumbar puncture. A nurse will greet you and explain what will happen. Sometimes this test can happen in your hospital room. Some boys and girls get a special sleepy medicine before the test starts. The doctor will give you a special mask to breathe through. It may be a little smelly, but it helps you fall asleep. If you are asleep during your lumbar puncture, you will not hear, see or feel any part of the test. When you wake up, it will be all done. Your back may feel a little sore afterwards.

If you do not have the sleepy medicine for your lumbar puncture, someone like your mom or dad may be able to stay in the room with you (this decision is up to your doctor). The nurse will help you get up on the bed and tell you how to lie down for the test. Usually you will be lying down on your side, with your knees curled up to your chest. This position helps to make the gaps between the bones in your spine wider to help the doctor get the CSF that he needs.

When it is time for the test, the doctor will first use special soap to clean the area on your back where the test will be done. Then the area will be covered with specially cleaned towels (sterile towels). This helps to keep germs away from your body.

Many hospitals have special creams (often called Emla cream) that you can put on top of your skin on your back where the test will be done. This is so that you will not feel too much of the pinch from the needle, but will feel pressure.

The doctor will then take a skinny needle and put it into the space between the bones on your spine. The doctor will collect a little CSF from your spine.

It is important to remember to stay still while you are having the test, this will make it easier and not as long. It may also help you relax by taking deep breathes.

When the doctor is finished, he will cover up the area with a dressing (Band-Aid). You may be sore in this area for a little while, especially after the numbing or freezing wears off. Sometimes after having this test, you may get a headache; the doctor may tell you to lie down for a while after the test to rest so that you do not get a headache.

What will the Lumbar Puncture feel like?

* The special soap used to clean your back may feel cold and wet.

* If you are not asleep for the test, you might feel some pain or pressure when the doctor puts the needle in to collect the fluid, sometimes it may have to move a bit and you may feel this as well.

* If you are awake for the test, it may get uncomfortable staying in the same position on your side.

* It is very important to stay still during the test if you are not asleep.

* After the test, your lower back may be sore for a while

* You may get a headache after having the test, so it is important for you to rest and lie down for a while after the test.

Preparing for the test

Your nurse will give you the information you need to help you get ready to have your lumbar puncture. Sometimes you may be given special sleep medicine for the test. This means that you would be asleep for the test, and not feel, hear or see anything. Or they may give you some special medicine to help you relax and make you feel sleepy. Ask your nurse or doctor if you will be asleep for the test.

When it is time for the test, remember to relax, breathe and stay still.

Remember

If you have any questions about the test, always ask!

This content has been reviewed and approved by health care team members at McMaster Children’s Hospital in Hamilton, Ontario. All content is for educational purposes only. For further information, please speak with your health care team.