A lumbar puncture, or spinal tap, is done to collect some of the fluid around the brain and spinal cord for testing. This fluid is known as cerebrospinal (sare-REE-bro-spine-al) fluid or CSF. This procedure is generally safe and only
During the lumbar puncture, a thin needle is placed into your child’s back. The needle goes into the spinal column below the spinal cord into an area called the subarachnoid (sub-a-RACK-noid) space. When the needle enters the spinal fluid space, the fluid will slowly drip through the needle into a test tube. Usually, less than one teaspoon of fluid is taken. The doctor may need to take more if special tests need to be done. The doctor will send the spinal fluid to a lab for testing and will discuss the test results with you when the tests are done.
Complications are rare with a spinal tap and most last only a short time. The following can happen:
- A headache that lasts from several hours to two days, with possible dizziness and nausea—feels better when patient is lying down
- An infection where the fluid was taken out
- Pain, discomfort, or numbness in the lower back
- A tingling sensation in the legs
Your child’s healthcare provider may numb the skin where the needle passes through, usually by putting a cream on the skin 1 to 2 hours before the procedure. The cream cannot be used in children under 1 month of age. If the cream cannot be used, your child’s doctor may give a numbing medicine using a small needle.
The lumbar puncture should take about 15 minutes or less. Your child will be asked to either sit or lie on one side. Next, your child will be asked to bring their knees to their chest and stay very still. If your child isn’t able to stay still, we may ask your permission to give your child a medicine to make them sleepy or less anxious.
The doctor will carefully clean the lower back. Next, they will place a sterile paper cloth with a hole in the center over your child’s back. This gives the healthcare provider a clean area to work so no germs will get on the needle or the providers’ hands. The doctor may then inject some numbing medicine, which can feel warm or sting as it goes into the back.
When the needle is inserted, your child may feel pressure or pain. You can help your child stay calm during the lumbar puncture by telling a favorite story, counting until the procedure is over, or blowing together slowly.
After your healthcare provider collects the cerebrospinal fluid, the needle is removed and a Band-Aid® is put on your child’s back. After the procedure, the doctor may want your child to remain lying down for 4 to 6 hours. This helps prevent your child getting a headache.