The purpose of a spinal tap, also called lumbar puncture or LP, is to get a sample of the fluid from the spinal column to find out if there is an infection or bleeding. The most common reasons people need this procedure include severe headache, fever with a stiff neck or vomiting, or confusion.

There are many other reasons to do a spinal tap and it is a very common, safe, and simple procedure done in emergency rooms and medical offices every day. People of all ages, from newborns to the elderly, may need this procedure. It can be done by a variety of healthcare providers including doctors, nurse practitioners, and physician assistants.

Information About Your Spinal Tap

The Preparation

You do not need to do anything to prepare for the spinal tap. You may be asked to confirm that the procedure has been explained to you and that you understand the risks. If you are allergic to numbing medications, like lidocaine, or cleaning agents, like Betadine, be sure to tell your provider.

The Procedure

A spinal tap usually takes about 10-15 minutes. You will be asked to lie on your side with your knees to your chest or to sit up and lean over. Both positions cause your back to arch, which opens the space between the bones of the spine making the procedure easier.

It will take a few minutes to prepare the tray for the procedure. Hold as still as possible so you stay in position. Certain areas of your body will be used as landmarks so the provider may need to feel your pelvic bone and spine to locate the right place. Your back will be cleaned with an antiseptic scrub then covered with sterile drapes. Be sure not to reach back or touch these drapes. A numbing medication will be injected before the spinal needle is inserted. This will usually cause a brief burning or stinging sensation.

The spinal needle will be inserted over the spine in your lower back. It will take 2-3 minutes to collect about a teaspoon of spinal fluid. The spinal needle is then removed and a bandage placed over the puncture site.

After the Procedure

You may be asked to lie flat on your back or stomach to reduce the possibility of developing a spinal tap headache. The puncture site may be sore for 1-2 days, but should not become red or drain pus. If this happens contact a healthcare provider immediately.

Initial test results of the spinal fluid may take 1-2 hours. Other tests, like cultures, may take a few days to weeks and requires follow up with your healthcare provider.

Benefits of a Spinal Tap

A spinal tap can find out if there is an infection, such as spinal meningitis, or bleeding, such as a brain hemorrhage. Because these conditions can be serious and require urgent treatment, having the spinal tap done right now is necessary. Also, since most spinal taps are negative, it can eliminate these conditions as the cause of your illness.

Risks of a Spinal Tap

A spinal tap is a very safe procedure and serious complications are rare. The spinal cord stops well above the level where the spinal tap is done and is not in danger of being injured. However, like all procedures, there are certain known possible complications as well as the risk of unforeseen complications. We will now discuss the common risks.

  • Spinal Tap Headache
    The most common complication is a “spinal tap headache.” This happens when the spinal fluid continues to leak from the puncture site. It can begin up to 2 days after the procedure and usually lasts for less than 2 days. This kind of headache gets worse when you sit up and better when you lay down. You can reduce the symptoms of a spinal tap headache by drinking plenty of fluids, especially those with caffeine. If these symptoms are severe or persistent you may require an additional simple procedure to alleviate the symptoms.
  • Bleeding
    Occasionally bleeding occurs during the procedure resulting in a “bloody tap”. This may require the spinal tap to be repeated at a different level or at a later time. There is an extremely rare chance that there could be enough bleeding into the spinal column that a procedure to stop the bleeding would be necessary. If you are taking blood thinners like warfarin, Coumadin, or heparin, or have a bleeding disorder like hemophilia, notify the doctor or nurse prior to the spinal tap.
  • Infection
    Sterile technique is used to avoid causing an infection, but there is a rare chance it could happen. If this occurs you may need to be treated with antibiotics. See your healthcare provider or return to the emergency room if you get redness, drainage, or severe pain around the puncture site. If you currently have fever or headache, they should resolve within 2-3 days. You should also seek immediate attention if you get a new fever or severe headache or have a significant change in your current symptoms.
  • Other Risks
    It is impossible to cover every potential risk. However, the benefit of having the spinal tap to check for a serious problem outweighs all of the potential risks. Even if a complication occurs, it does not mean anything was done wrong.

When to Seek Medical Care

After you go home, you should contact your healthcare provider or return to the emergency room if any of the following occur:

  • Redness, increasing pain, or drainage at the puncture site.
  • A new fever or severe headache.
  • Weakness or loss of sensation in your legs.
  • Inability to control your bowel or bladder.
  • Your symptoms do not get better as expected.

If you are discharged home, you will usually be instructed to follow up with your healthcare provider in 1-3 days.

What We Have Learned

  1. A spinal tap gets a sample of spinal fluid to find out if there is an infection or bleeding.
    True or False
    The Answer is True.
  2. Lying flat on your back or stomach after a spinal tap does not reduce the risk of developing a spinal tap headache.
    True or False
    The Answer is False
  3. You should contact a healthcare provider immediately if the puncture site becomes red or drains pus.
    True or False
    The Answer is True

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Special Thanks to Medtronic for their help in the making of this production.

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