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What is a lumbar puncture?

  • What is a lumbar puncture?

    A lumbar puncture or spinal tap is the insertion of a needle in between the bones, called vertebrae, that make up the lower portion of the spine (lumbar region) and into the fluid-filled space called the spinal canal. The purpose of this procedure is to withdraw some of the cerebral spinal fluid that surrounds the spinal cord for testing, or to administer a medication into the spinal canal.

    lumbar puncture

    What you should know about this procedure

    • You will be assisted into one of two positions: lying on your side with your legs pulled up to your abdomen and your chin tucked to your chest, as in the above diagram, or sitting on the side of the bed, leaning forward with your arms and head resting on the overbed table.
    • It's very important to maintain the position and remain very still during the procedure to avoid moving the needle.
    • Please tell your doctor if you have an allergy to betadine or xylocaine.
    • Your skin will be cleansed with a solution (usually betadine).
    • The physician will explain the procedure and get your consent if he/she has not already done so.
    • A small amount of local anesthetic (usually xylocaine) is injected into the area to reduce discomfort caused by the needle. With this anesthetic you may still experience some initial discomfort but you should mainly feel pressure from the needle. Please let your doctor know if you are uncomfortable.
    • When the procedure is completed, a band-aid is applied over the area. The doctor will let you know whether you will need to lie flat for a specific period of time.
    • After the procedure, it's common to have a mild to moderate headache. Please inform your doctor if any of the following occurs: difficulty urinating, pain, swelling, drainage or bleeding at the injection site, or any headaches or fevers.
    • If you receive intravenous medication before the procedure to help you relax, you should not operate heavy machinery, drive a car, drink alcohol or make any important decisions for 12 to 24 hours after the procedure. Your doctor will let you know when you can resume your regular activities.
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