HF 4229

Musculoskeletal Radiology: Lumbar Puncture

Your lumbar puncture is scheduled on ______________________________ at UW Hospital.

Please report to Radiology (G3/3) on the 3rd floor at _____________. 

Your doctor has ordered a test for you called a lumbar puncture (also known as a spinal tap). This handout explains what will happen before, during, and after the test. Your nurse will go over this sheet with you. Please ask questions. If you have questions or concerns after you go home, please call the numbers listed at the end of this handout.

Please let your doctor or nurse know if: 

  • You are allergic to novocain or lidocaine. 

  • You have had previous back surgery. 

  • You take a medicine that is a blood thinner.

What is a lumbar puncture?

A lumbar puncture involves placing a needle between the bones of the lower back. The purpose of the spinal tap is to test the fluid, known as cerebrospinal fluid or CSF, which flows around the spinal cord and the brain. This fluid acts as a shock absorber for the central nervous system. Tests on CSF can tell many things about your body.

The procedure is done at the bedside or in the clinic. The use of fluoroscopy allows the doctor to guide the needle into the right position. This can make the procedure easier; but, it does not mean that there will be less pain or you will be less likely to have complications.

Before the Procedure

  1. Please arrange to have someone drive you home.

  2. Bring along any medicines you will need to take during the day including acetaminophen (Tylenol®).

  3. Before the exam, your doctor may order blood tests. They want to know that your blood will clot in a normal way. This will let the doctors in Radiology know that it is safe to do the procedure.

The Procedure

You will be asked to lie down either on your stomach or side on the exam table. You must remain as still as you can during the procedure.

The doctor will decide where to insert the needle by looking at the X-rays and feeling your back. The doctor will put on sterile gloves and clean your back. A sterile towel will be draped over your back. Do not touch your back or the sterile towel.

Next, you will receive a shot to numb the site where the puncture will be. This is much like the dentist giving you novocain before filling your teeth. The site will become numb in less than a minute. Then the doctor will insert a needle between the bones at the chosen spot. 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 doctor may attach a gauge to the needle to measure the fluid pressure. Then, some of the CSF will drain into several tubes. The CSF will come out through the needle drop by drop, much like a dripping faucet. Once enough fluid has been taken for testing, the needle will be pulled out. Your back will be cleaned, and a band-aid will be placed over the site. The entire test will last about 30 to 45 minutes.

After the Test

You will need to lie flat in bed for up to 1 hour so you don’t get a headache. If you are an outpatient you will need to be watched in the Radiology Recovery Unit. You may lie on your side, back, or abdomen, but do not lift your head for long periods of time

You should drink plenty of fluid after the test and over the next 1 – 2 days. These fluids will help replace the CSF fluid that was taken for tests. Your nurse will check the puncture site for redness or swelling before you leave.


The length of time before you have the results of your test varies. Some results are ready in 1 to 2 days. Others may take weeks. Results will be sent directly to the doctor that ordered your test – ask in the recovery unit if you are not sure.

Home Care

  • Keep resting for the rest of the day. Plan to do quiet things like reading, watching TV, etc.

  • Recline in bed or on a sofa, until the next morning.

  • Keep drinking plenty of fluids. It is best if they contain caffeine.

  • The morning after the test, you may take a bath or shower and remove the band-aid. You may also resume your normal routine.

  • If you get a headache after starting activity, return to resting, lay flat and increase your intake of fluids with caffeine.

  • You may take any over the counter pain killer (ibuprofen, Tylenol®, naproxen) you may have at home for any pain.

  • No heavy lifting, twisting, bending or strenuous exercise for one week to allow the puncture site to heal.

When to Call the Doctor

  • A severe headache that is not relieved by aspirin or acetaminophen (Tylenol®)

  • Dizziness

  • A stiff neck

  • Nausea or vomiting

Phone Numbers

If you need to speak to someone about the procedure call the Neuroradiology Clinical Program Coordinator at (608) 890-7291

After hours or weekends, please call the hospital paging operator at (608) 262-2122 and ask to talk to the Neuroradiology Fellow on-call.

If you have a question about the results, please call the doctor that ordered the study.