Can you be put to sleep for a spinal tap

This description is the personal experiences of a woman with MS who underwent a lumbar puncture during her diagnosis

Assuming that this is not an emergency,you will have been given a date and time for your lumbar puncture. If that does not suit you, you can ring up and ask to change it. If you can’t make it, let the hospital know – I have always found them very helpful.

The hospital usually sends information about what to expect and what to bring with you. You may be at the hospital for a few hours, but you are not likely to have to stay overnight. However you may want clothes that are suitable for resting in bed and things you can do whilst resting. You don’t usually have to stop eating or drinking before the test. In fact it may help avoid or reduce any post procedure headache if you are well hydrated. You should take all your medicines, unless told not to do this.

Whether you want someone with you on the day of the test is a personal choice. You may not feel able to go home by yourself and it is not recommended to drive yourself home afterwards, so having someone to go home with you or to take you home may be sensible.

The doctor (or other professional) doing the test will discuss with you what they are going to do. When talking to you, they must check who you are and say who they are. They will explain what they are proposing to do, how they expect to do it, why they think it is appropriate for you, what the common complications are and, if there are any, significant possible complications. This is your opportunity to ask questions. They will also ask you to sign a form consenting to the procedure that they have described to you.

The cerebrospinal fluid is the fluid that surrounds the brain and spinal cord, all within a thin membrane sack (the dural sac). The dural sac is entirely surrounded by the spine, passing through holes in the back of each vertebra. Samples are usually taken from the lower back, in the bottom part of the dural sac, where there is generally a good amount of CSF around the nerves that go to the legs.

When everything is ready to start, the doctor will ask you to get into a position that curls your lower back. This may be lying on your side in a sort of foetal position with your knees up and head down, or sitting up in a chair with your head down towards your knees, possibly leaning over a pillow to get the shape. These positions mean that the spaces between the bony vertebrae in the lower back are as wide as possible, giving a bigger target to aim for and makes the procedure easier.

Getting a sample of cerebrospinal fluid (CSF) is a bit like getting a sample of blood for a blood test. A needle needs to be put in the right place and the fluid can be allowed to flow out or removed with a syringe. When getting a sample the needle has to go between two adjacent vertebrae, through the protective dural membrane and into the CSF.

The doctor will clean your lower back to avoid infection, using iodine or another liquid. This is usually rather cold and iodine leaves a yellowish stain, which may get on your clothes. They will probably then put sterile paper or material sheets around your back. Some local anaesthetic will be put into your skin through a small needle. This stings but only for a moment. They will probably put more in a bit deeper to numb the underlying tissues, which you may or may not feel. The anaesthetic works within seconds, but if you are feeling sharp pains during the lumbar puncture, tell them and they can give you more.

The needle used to collect the CSF is very thin – much thinner than the sort of needle used for a blood test – and may need to be quite long. When the doctor is putting the needle in, it may feel as if someone is pushing on your back, though some people feel nothing. There are lots of nerves within the fluid in the spinal canal but usually they have room to move out of the way. If one of the nerves is touched, it can give a nasty ache or pain, usually in a leg.

Once the needle is in the right place, it takes a few seconds to get the sample. It is important to stay as completely still as possible for the time of collection of the sample, but this is only is a minute or two. Then the needle is removed.

The tiny hole in the membrane caused by the lumbar puncture usually seals itself, although this seal is not very strong. Immediately after the test you will be told to keep still and move carefully. You will probably be told to stay lying flat in bed for an hour or so, possibly up to six hours. If things are straightforward, you may be able to leave after two or three hours.

Because of the loss of the fluid and the change in the pressure around the brain, a post-procedure headache is very common. Unfortunately it can be very unpleasant indeed, but not everyone gets one. The body replaces the missing CSF, but this does take a day or so. The doctor may suggest taking some simple pain relief on the off chance, or they may prefer you to wait until you get a headache. It is thought to be helpful to stay well hydrated after the test and it is probably a good idea to take things a bit gently for a day or so.

You should be supplied with information about what to do if there are any other problems, such as swelling at the site of the puncture or severe headache that doesn’t get better with simple painkillers.

Multiple Sclerosis: Getting Through a Spinal Tap

Can a Spinal Tap Cause Paralysis?

A spinal tap can be uncomfortable, but the fear of a spinal tap causing paralysis is unfounded.

Paralysis can occur when the spinal cord, which runs from the brainstem to the top of the lumbar vertebrae and usually ends in the space between the first and second lumbar vertebrae, is damaged. During a spinal tap, the needle is injected between the third and fourth or fourth and fifth lumbar vertebrae in the lower back, too low to pierce the spinal cord.

In most people, a spinal tap causes no more than a small amount of discomfort. Some may feel some burning and nerve twinges when the needle is inserted.

“I tell women who’ve had epidurals that a spinal tap will feel similar to that,” Dr. Stone says.

Side Effects and Complications

Some people develop a headache — called a “spinal headache” — after a spinal tap. Spinal headaches usually start within a day or two after a lumbar puncture but can occur several days later. They are thought to result from an internal leak at the puncture site in the dura mater, the tough membrane that surrounds the spinal cord.

You’ll know it’s a spinal headache if the pain goes away when you lie down but reappears when you sit or stand.

Home remedies for a mild spinal headache include:

  • Lying down in a comfortable position
  • Drinking liquids
  • Taking an over-the-counter analgesic, such as aspirin

Let your doctor know if you develop a headache following a spinal tap, particularly if your pain or any other symptoms such as nausea are severe or get progressively worse.

According to Orhun Kantarci, MD, an associate professor of neurology at the Mayo Clinic in Rochester, Minnesota, spinal headaches usually last no longer than three days, and they usually go away on their own.

However, Dr. Kantarci says, about one in 25 people needs what’s called a blood patch. For that, a doctor draws blood from your arm and injects it into the area of the lumbar puncture to cause the leakage to clot.

Other potential complications of a spinal tap include infection and bleeding, but both are rare. If you experience signs of infection such as fever, severe neck stiffness, and pain or redness at the puncture site, however, contact your physician immediately.

Lumbar Puncture

A lumbar puncture (LP) or spinal tap may be done to diagnose or treat a condition. For this procedure, your healthcare provider inserts a hollow needle into the space surrounding the spinal column (subarachnoid space) in the lower back to withdraw some cerebrospinal fluid (CSF) or inject medicine.

CSF is a clear fluid that bathes and cushions the brain and spinal cord. It is continuously made and reabsorbed in the brain. CSF is made up of cells, water, proteins, sugars, and other substances that are essential to maintain balance in the nervous system.

Why might I need a lumbar puncture?

A lumbar puncture may be done for various reasons. The most common reason is to remove a small amount of CSF for testing. This can help in the diagnosis of various disorders. The fluid is tested for red and white blood cells, protein, and glucose (sugar). The clarity and color of the fluid are also checked and it is tested to see whether bacteria, viruses, or abnormal cells are present. Excess CSF may also be removed in people who have an overproduction or decreased absorption of the fluid.

A lumbar puncture procedure may be helpful in diagnosing many diseases and disorders, including:

  • Meningitis. An inflammation of the membrane covering the brain and spinal cord. The inflammation is usually the result of a viral, bacterial, or fungal infection.

  • Encephalitis. An inflammation of the brain that is usually caused by a virus.

  • Certain cancers involving the brain and spinal cord

  • Bleeding in the area between the brain and the tissues that cover it (subarachnoid space)

  • Reye syndrome. A sometimes fatal disease that causes severe problems with the brain and other organs. Although the exact cause of the disease is not known, it has been linked to giving aspirin to children. It is now advised not to give aspirin to children during illnesses, unless prescribed by your child’s healthcare provider.

  • Myelitis. An inflammation of the spinal cord or bone marrow.

  • Neurosyphilis. A stage of syphilis during which the bacteria invades the central nervous system.

  • Guillain-Barré syndrome. A disorder in which the body’s immune system attacks part of the nervous system.

  • Demyelinating diseases. Diseases that attack the protective coating that surrounds certain nerve fibers – for example, multiple sclerosis or acute demyelination polyneuropathy.

  • Headaches of unknown cause. After evaluation and head imaging if necessary, a lumbar puncture may be done to diagnose certain inflammatory conditions that can result in a headache.

  • Pseudotumor cerebri (also called idiopathic intracranial hypertension, or IIH). In this condition,pressure within the subarachnoid space is elevated for reasons that are not clear. A lumbar puncture is only done in this condition after evaluation and head imaging.

  • Normal pressure hydrocephalus. A rare condition affecting mainly older people in which there is a triad of loss of urinary control, memory problems, and an unsteady gait. A lumbar puncture is done to see if the pressure of the CSF is elevated or not.

In addition, a lumbar puncture may be used to measure the pressure of the CSF. The healthcare provider uses a special tube (called a manometer) to measures the pressure during a lumbar puncture.

Finally, a lumbar puncture may be done to inject medicine directly into the spinal cord. These include:

  • Spinal anesthetics before a surgical procedure
  • Contrast dye for X-ray studies – for example, myelography
  • Chemotherapy drugs used to treat cancer

Your healthcare provider may have other reasons to recommend a lumbar puncture.

Lumbar Punctures – FAQs and Myths

Lumbar punctures, cerebrospinal fluid, and biomarkers—these are three terms that form the horizon of our center’s research. Biomarkers are biological indicators that may lead us to a prevention or cure for Alzheimer’s disease, cerebrospinal fluid is the substance in which some of these biomarkers are found, and a lumbar puncture is the method used to access cerebrospinal fluid.

Often, when we tell people that lumbar punctures are a common part of our research, we are met with a bit of reservation. That reservation is understandable, but we hope that by providing clear information about the procedures and answering some common questions about the procedures, we can help make lumbar punctures seem less invasive and risky.

The needle location of the lumbar puncture. A lumbar puncture video can be accessed on YouTube.

What is a lumbar puncture?

A lumbar puncture (also called a spinal tap or an LP) is a common medical procedure in which doctors remove a small sample of cerebrospinal fluid (CSF) from a person’s lower back (“lumbar” region). During an LP, participants lie on their side, which allows doctors to easily access the area of the lower back where the LP will occur. Once participants are in position, doctors use a local anesthetic to numb the area and then use a thin needle to draw out a small amount of spinal fluid. Because the anesthetic numbs the area, the LP should not be particularly uncomfortable or painful. After an LP, participants occasionally feel mildly sore as a result of staying in an unfamiliar position during the procedure. If participants are sore after an LP, they can take a standard pain reliever like Tylenol.

Are lumbar punctures safe?

Yes. Our center has improved the procedures for research lumbar punctures and has created safety guidelines that are followed throughout the field. To read more about the safety and acceptability of lumbar punctures, please click here.

Will I have a spinal headache after the LP?

We have performed over 2,000 LPs at the UW ADRC and have improved the procedure to reduce discomfort and to minimize the chance of LP-related headaches (known as spinal headaches). In fact, less than one percent of our participants experience significant spinal headaches. However, when they do occur, these headaches can be quite painful. If someone gets a mild headache following an LP, we treat it with Tylenol and beverages that are high in caffeine. In the rare case of a severe headache, we perform a simple medical procedure called an epidural blood patch to relieve the pain. Most spinal headaches can be avoided by following the instructions and follow-up care provided by our physicians.

What is CSF and why is it so important?

CSF is a clear, colorless liquid that is in direct contact with the brain. It provides a cushion to the brain and spinal cord and may serve some purpose in the chemistry of the brain (which is not clear to us at this point). Importantly, since the CSF interacts very closely with the brain, many researchers believe that it can provide a more direct window into changes that may be occurring there. CSF contains a variety of proteins that researchers measure and analyze. The goal of this analysis is to identify markers (biomarkers) for Alzheimer’s disease that will improve with accurate diagnosis, “preclinical” diagnosis in persons with no memory symptoms who are destined to have Alzheimer’s in the future, and monitoring response to therapies. This type of monitoring will be particularly important as we try to develop new treatments.

What happens to my CSF after it is collected?

At the ADRC, CSF samples are kept within a collection called the ADRC Research Repository. This repository has the largest collection of CSF samples from individuals with no memory complaints (control participants) in the world, and is utilized by a large research community. These samples are particularly important as a group because the collection can be studied for specific research questions related to Alzheimer’s disease.

The Lumbar Puncture Myth Buster

As published in Dimensions

Dr. Elaine Peskind, UW Professor of Psychiatry and former director of the UW ADRC Clinical Core, reinvented the way research lumbar punctures, or spinal taps, are done, making them safer and less painful for research participants. But urban legends and myths of pain, meningitis, and paralysis are still associated with the procedure. Dr. Peskind, who has performed more than a thousand lumbar punctures during her work at the ADRC, takes a look at a handful of these fables and reveals the truth about research lumbar punctures.

MYTH: Lumbar punctures are really painful.

The discomfort associated with a lumbar puncture seems to vary from person to person. Most people report that the only painful or uncomfortable part of the procedure is a very brief sting they experience when the local anesthetic or numbing medicine is injected. This local anesthetic is similar to the one you would receive at the dentist, and it is used to prevent pain during the lumbar puncture. As the needle for the lumbar puncture is positioned to collect spinal fluid, most people describe the feeling as a pressure sensation. In a study we did at the ADRC, we found that, overall, anxiety and pain ratings were low among the research participants who had lumbar punctures. Most people are surprised at how comfortable the procedure is, and occasionally a person will sleep through the procedure.

MYTH: There is a chance that a person could get meningitis by participating in have a lumbar puncture.

People cannot develop meningitis from a lumbar puncture that is conducted properly. The worry over meningitis and lumbar punctures perhaps arose because bacterial meningitis, which is a condition where bacteria makes its way into the spinal canal, is diagnosed by using a lumbar puncture to collect spinal fluid for testing.

MYTH: If a person gets a lumbar puncture, that person will have a bad headache afterwards.

When doctors perform a lumbar puncture, they puncture a fluid-filled sac that surrounds the brain and spinal cord. Spinal headaches occur when the spinal fluid continues to leak (under the skin) from this puncture. A true spinal headache worsens when a person is sitting or standing and improves when that person lies down. After a lumbar puncture that is conducted for medically necessary reasons, 10 to 30 percent of people develop a spinal headache. However, for research lumbar punctures at the ADRC, we use techniques that make the headache rate much lower—less than 1 percent of our subjects report having spinal headaches. This difference is mainly caused by the gauge (thickness) of the lumbar puncture needle and the shape of the needle tip. In the ADRC research lumbar punctures, the needle inserted into the sac has a smaller gauge and duller tip than the needles that are commonly used during medically necessary lumbar punctures. This difference means that in a research lumbar puncture at the ADRC, the tip of the research needle slides between the fibers of the sac that contains the spinal fluid rather than cutting through it. Because those fibers are not cut and because the hole left by the needle is smaller, the puncture site seals quickly and prevents the spinal fluid from leaking out.

MYTH: If the doctor sneezes while someone is undergoing the procedure, that person will become paralyzed.

The spinal cord ends about five inches above the spot where the lumbar puncture needle is inserted. Because the needle is inserted well below where the spinal cord ends, there is almost no chance of nerve damage or paralysis. Nerves branch off the spinal cord and dangle loosely down through the lower part of the spine. Sometimes the needle may brush against one of these nerves, which may cause a brief “electric” twinge to go down the person’s leg but results in no other symptoms, particularly not paralysis. This feeling usually goes away quickly, but if the twinge returns while spinal fluid is being withdrawn, our doctors will quickly readjust the needle, which usually stops this brief discomfort.

Spinal Tap and Lumbar Puncture – FAQ

  • What is it?
  • Will my child need to be hospitalized?
  • Why does my child need it?
  • Will it hurt?

We’ve tried to provide some answers to those questions here, and your child’s doctor can talk more about the test with you when you meet.

Background on the brain and spinal cord – the central nervous system (CNS)

Your child’s central nervous system (CNS) made up of her brain and her spinal cord. It’s responsible from collecting information from and sending information to all parts of her body.

The spinal cord is a long, thin bundle of tissues and cells that extends downward from her brain. It’s nestled in the spinal canal and protected by the vertebrae, just as the brain is protected by the skull.

In the vertebrae, bones are stacked on top of one another and connected by joints, for flexibility. In between are disks that provide cushioning. The disks also create little spaces between the bones, spaces that are covered by a thin membrane. When we perform a lumbar puncture, we go through that thin membrane to get to the spinal canal.

The brain and the spinal cord are also bathed in (and protected by) a fluid produced in the brain called cerebrospinal fluid. This fluid can be useful in diagnosing a condition your child may have.

What is a lumbar puncture?

A lumbar puncture is a common procedure in which we ask your child to curl up in a ball, and then we use a special needle to gain access to her spinal canal through her back. This lets us remove a bit of fluid for testing, deliver medications or measure/relieve pressure in her spinal canal. This sounds invasive and painful, but while it may feel uncomfortable and some children have headaches afterwards, it feels more like a pinch that lasts a few minutes. Most children have lumbar punctures with local anaesthesia, meaning that they’re alert, but the area of the puncture is extremely numb.

Why would my child need a lumbar puncture?

Your child’s doctor might request a lumbar puncture in order to:

  • take a sample of the cerebrospinal fluid so that it can be examined in a lab
  • inject medication (such as anesthesia or chemotherapeutic agents) directly into the CSF, so her body can use it most effectively
  • remove excess cerebrospinal fluid (decreasing spinal canal pressure) in children with hydrocephalus or intracranial hypertension
  • measure the amount of cerebrospinal fluid pressure in the spinal cord

If your child’s nervous system is damaged, it can cause delays in her normal development and functioning. Early detection means that we have a better chance of identifying the cause, can treat her quickly and decrease the chance of long-term complications.

What conditions are associated with lumbar punctures?

Conditions most commonly associated with lumbar punctures include:

  • infections such as meningitis (bacterial, viral, parasitic or fungal)
  • lymphoma
  • leukemia
  • other cancers of the brain or brain system.
  • inflammation of the blood vessels (vasculitis)
  • auto-immune disorders such as multiple sclerosis

How do we prepare for a lumbar puncture?

Most often, no special preparation is needed. If your child will have the procedure under sedation, her doctor will give you some preparation guidelines to follow.

Before coming to the hospital, explain to your child what will happen during the test and encourage her to ask questions and express her feelings.

Will my child be under sedation?

Most children have lumbar punctures with local anaesthesia, meaning that they’re alert, but the area of the puncture is extremely numb. Sometimes, we use intravenous (IV) sedation, which makes your child very sleepy. On rare occasions, the procedure is done under general anesthesia, in an operating room. You and your child’s doctors will decide together what is best for your child.

What happens during the procedure?

1. Once your child is ready for the test, we’ll have her lie on her side and curl up in a tight ball so the physician can access her lower back. A technician or nurse stand beside your child to help her hold still and explain what the physician is doing. Remaining still is very important and will make the test go more smoothly.

2. We feel your child’s back for a space between the bones of the lower part of the spine to insert the needle. He or she will clean the spot with a special solution, and then apply a numbing cream to your child’s skin.

3. We further numb the spot by injecting a special medication. This stings for a few seconds, but it makes the spinal tap less painful. Then, we put the special needle through the numbed skin, and into the space where the CSF is found.

4. Your child feels some pressure while the needle is being pushed in. It’s important she stays still during this time. The cerebrospinal fluid will begin to drip out of the needle and a small amount will be collected in test tubes. We also measures the pressure in her spinal canal.

5. If we need to inject medication in the spinal canal, we give it through the same needle after the cerebrospinal fluid is collected.

6. We remove the needle and clean and bandage the area on your child’s back.

How does a spinal tap measure pressure?

After the needle is inserted, the doctor attaches a hub with a three-way valve. One opening is connected to a manometer (a little tube that measures pressure). Cerebrospinal fluid rises up the manometer just like mercury or water rises up a barometer in response to atmospheric pressure, and can be measured that way.

How long does a lumbar puncture take?

About 30 minutes. We also ask that your child lie down immediately afterwards here at the hospital for several hours before going home. Please be assured that during and after the test, we do everything we can to make sure she’s as comfortable as possible.

Where will it take place?

Lumbar punctures usually take place in a doctor’s office – most often a neurologist – that has been equipped to do this procedure.

Who will be in the room with my child during the procedure?

Your child will be with her doctor or nurse practitioner performing the lumbar puncture, and a nurse or clinical assistant who will help. There may be another doctor in to assist or supervise, too. And parents are always invited to stay, if they think it will be helpful for their child to have them there.

What happens after the test?

After the test, your child will lie down immediately afterwards here at the hospital for several hours before going home. You can read to your child or play quietly with her while she is in bed, and encourage her to drink lots of fluid.

Is there anything special my child should do when we get home?

We recommend rest and quiet activities for 24 hours. If your child has a headache, which is fairly common, have her drink lots of fluids and lie down for a few hours.

Are there any signs I should watch out for once my child is brought home?

Most children do very well after a lumbar puncture, but contact your child’s doctor if:

  • her headache persists into the next day, and she has been taking it easy and drinking a lot of fluids
  • you notice (or your child complains of) anything that may be a neurological concern, such as:
    • changes in vision
    • unsteadiness on her feet
    • significant discomfort at the site of the puncture
    • changes in sensation in her legs

When will we get the results of the test?

This all depends on which tests the lab(s) run. Simple tests are ready the same day, if not within a few hours. If we’re looking for bacteria, we’ll know the results within 72 hours. Other, more demanding tests may be ready in a matter of days or weeks; and specific biochemical tests that are looking for certain antibodies may take six to eight weeks to come back.

Once the results are in, your child’s doctor will explain the lab report to you, and then you’ll discuss next steps together.

Q: Does it hurt?
A: We will give your child local numbing medication, so your child won’t feel anything as the needle goes in and out. Sometimes children have an electrical sensation in the leg, which shouldn’t last. Your child’s muscles may feel a little crampy as have her curl up in a tight ball, but that goes away, too.

Q: Could my child be paralyzed from this?
A: No. Lumbar punctures are done in an area of your child’s body that’s below the spinal cord, so there’s no risk of accidentally contacting it.

Q: How long does it take?
A: The procedure takes about 30 minutes, but we ask that your child lie down here at the hospital for a few hours afterwards.

Q: Are there any risks or complications?
A: As with many medical procedures, there’s a risk of infection or bleeding. But we’re very careful, and the risk of infection here at Children’s is extraordinarily low.

Q: When will we know the results?
A: It depends on the tests – it could be a matter of hours for routine tests, and six to eight weeks for some more in-depth tests.

How does a spinal tap help diagnose multiple sclerosis (MS)?

The spinal tap is a routine diagnostic test that was first performed in 1891. From its beginning, the spinal tap has been the target of a lot of bad press. In reality a spinal tap is a simple, relatively painless procedure done in a doctor’s office, an outpatient clinic or a hospital. After Novocain is administered to the lower back, a needle is inserted and spinal fluid withdrawn. This is done well below where the spinal cord ends, so there is no danger. It is no more traumatic than having blood drawn. But in spite of its benign nature, the average person still views the spinal tap as the one test to fear. This is unfortunate, since various tests on spinal fluid have been very valuable in helping to diagnose multiple sclerosis (MS).

IgG (immunoglobulin G) is the substance that represents increased antibody formation. An elevated level in the spinal fluid suggests the presence of an autoimmune phenomenon. Another type of immune abnormality, the oligoclonal band (OB), has been picked up in the spinal fluid of as many as 90 percent of MS patients. A third abnormal finding is the presence of a breakdown product of myelin called myelin basic protein (MBP). Until the MRI, identifying these through a spinal tap was as close as it was possible to get to a diagnostic test for MS. But increased IgG can also be seen in other diseases such as encephalitis, lupus, meningitis, and Guillain-Barre syndrome. Oligoclonal bands and myelin basic protein can also be found in other demyelinating diseases besides MS.

Today many neurologists do not feel that these laboratory tests are necessarily the best way to confirm an MS diagnosis. Still, a spinal tap may be necessary if problems other than MS are also suspected, such as an infection in the central nervous system.

Lumbar puncture

A lumbar puncture removes a small amount of cerebrospinal fluid (CSF) from the space around the spinal cord so that it can be looked at under a microscope. CSF is the fluid that surrounds and cushions the brain and spinal cord. A lumbar puncture is also called spinal tap and cerebrospinal fluid (CSF) collection.

Why a lumbar puncture is done

A lumbar puncture is done to:

  • examine the CSF for cell counts, and for protein and glucose levels
  • measure the pressure of CSF in the space around the spinal cord
  • remove CSF to decrease pressure in the space around the spinal cord
  • check for cancer of the brain and spinal cord
  • check for cancers that may involve the central nervous system, such as leukemia or lymphoma
  • check for infection or inflammation, bleeding around the brain or spinal cord and diseases of the brain and spinal cord
  • put an anesthetic into the CSF to freeze the spinal cord (spinal anesthetic)
  • inject chemotherapy drugs into the CSF to treat leukemia and other types of cancer of the central nervous system (intrathecal chemotherapy)
  • put a contrast medium into the CSF to make the spinal cord and CSF appear clearer on an x-ray

How a lumbar puncture is done

A lumbar puncture may be done in a clinic or hospital. The entire procedure usually takes 15 to 30 minutes. (The actual CSF collection usually only takes a few minutes.) A healthcare professional will help you get into the proper position and will support you in that position throughout the procedure. It is important to lie or sit as still as possible during a lumbar puncture.

A lumbar puncture is usually done with you lying on one side with your knees drawn up toward your chest and your chin tucked into the chest, sort of like a letter C. It may also be done with you sitting up and leaning forward with your back to the doctor. These positions help widen the spaces between the bones of the spine (called the vertebrae) so that the needle can be inserted more easily.

The skin on your back is cleaned with an antiseptic solution. A local anesthetic to numb the area is injected into the skin over the lower spine. You may feel a burning sensation as the anesthetic goes in.

A spinal needle is inserted through the skin and then through the space between the vertebrae until it enters the space that contains the CSF. The needle does not enter the spinal cord because it is inserted in the lower back. The spinal cord doesn’t extend this far.

Most people feel pressure or a stinging sensation when the spinal needle is inserted. If the needle touches a nerve, you may also feel tingling down one of your legs. This is temporary.

A small amount of CSF is collected and sent to the lab to be looked at or more CSF is removed to lessen the pressure around the spinal cord. Chemotherapy or other medicine may be injected into the CSF if that is part of your treatment plan.

The needle is then removed, the area cleaned and a small bandage is put on.

To lessen the chance of headache after the procedure you will be told to lie on your back for about 1 to 2 hours. You will be encouraged to drink extra fluids and to rest for several hours after the test.

Side effects

Serious problems from a lumbar puncture are not common. Potential side effects may include:

  • headache
  • backache
  • nausea and vomiting
  • dizziness
  • irritation of a nerve may cause temporary numbness, tingling or pain down your legs
  • infection where the needle was inserted
  • bleeding into the spinal canal

Call the doctor if you have:

  • a severe headache or a headache that lasts longer than a week
  • signs of infection, such as fever or chills
  • redness, swelling, pain, bleeding or discharge from the area where the needle was inserted
  • tingling or numbness in your lower back or legs

What the results mean

The CSF, which is generally clear and colourless, is examined and tested in the laboratory.

  • Cloudy CSF or a high white blood cell count in the CSF may mean you have an infection.
  • Blood or red blood cells in the CSF may mean there is bleeding in or around the brain or spinal cord.
  • Cancer cells in CSF may indicate primary or metastatic brain tumours, leukemia or lymphoma.
  • Large amounts of protein may suggest infection, bleeding or disease.
  • A low glucose level may mean you have an infection.
  • Increased CSF pressure may be caused by swelling or bleeding in the brain, infection or other problems.

What happens if the result is abnormal?

Depending on the result, your doctor will decide if you need more tests, any treatment or follow-up care.

Special considerations for children

Preparing children before a test or procedure can lower anxiety, increase cooperation and help them develop coping skills. Preparation includes explaining to children what will happen during the test, including what they will see, feel, hear, taste or smell.

You may be able to be in the room with your child during the test.

Keeping still or holding a certain position for a long time can be stressful for a child. Rehearsing the position before the test can help the child feel more in control and understand what they need to do. A nurse may help children stay still by holding them in place during the procedure.

Depending on the age of the child, sedation may be used. If sedation is used, your child may not be allowed to eat or drink several hours before the test and may have an IV.

A cream may be given to numb the area where the needle will be inserted. If you need to put the cream on at home beforehand, the doctor or nurse will show you what to do.

Preparing a child for a lumbar puncture depends on the age and experience of the child. Find out more about helping your child cope with tests and treatments.

Lumbar Puncture (Spinal Tap)

A lumbar puncture, also called a spinal tap, is an image-guided procedure performed on the lower back which removes fluid that surrounds the brain and spinal cord to examine it for cancer cells or infection. This fluid is called cerebrospinal fluid or CSF and is a clear liquid that delivers nutrients to the brain and cushions the spinal cord and brain. A lumbar puncture may also be performed to inject medication into the spinal column. Children and adolescents are usually given anesthesia or sedation before a lumbar puncture is performed.

The above video demonstrates a lumbar puncture in a child undergoing cancer treatment. This video was designed to educate parents and caregivers by showing an actual patient being accessed for treatment. Our intent with this video is to help you, and your child if you chose to show it to them, understand what will happen when your child has this procedure.

This activity is supported by a contribution from Lilly USA, LLC.

Performing the Procedure

  • A child will usually lie on his or her side, chin tucked to the chest and knees pulled up to the chest. A staff member will help your child get into the proper position and support that position throughout the procedure.
  • Lying still can be stressful for children. Rehearsing the position before the test can help your child feel more in control and understand what he or she needs to do.
  • In some cases, older children can sit up and curl the back by tucking the chin to the chest.
  • When the back is in a curved position, a needle is placed between the bones of the spine (vertebrae) below the level of the spinal cord.
  • Fluid from the spinal canal is then removed through the needle and collected into a tube that is sent to a laboratory to be tested.
  • For some types of cancer, chemotherapy may be given into the spinal canal through the same needle after the cells are removed for testing.

Spinal Tap (Lumbar Puncture)

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What Is a Spinal Tap/Lumbar Puncture?

A lumbar puncture, or spinal tap, is a medical test that involves collecting a small sample of cerebrospinal fluid (CSF) for examination. This clear, colorless liquid helps “cushion” the brain and spinal cord, or central nervous system.

Doctors use the fluid sample to look for signs of possible infections or other illnesses.

Why Are Spinal Taps Done?

The central nervous system is made up of the brain and spinal cord. It’s the “command center” for the body. The spinal cord sends signals to and from the brain and the brain interprets them.

Cerebrospinal fluid constantly flows around the central nervous system while protecting it. Becausee it “bathes” the central nervous system, CSF can also pick up chemicals and impurities in the brain and spinal cord.

A fluid sample can provide a lot of important information about a person’s health. So a lumbar puncture can help doctors find or rule out many diseases or conditions.

Most often, a spinal tap is done is to see if a child has meningitis (inflammation and infection of the covering of the brain and spinal cord). Other conditions that can be detected include Guillain Barré syndrome, multiple sclerosis, cancer that affects the nervous system, and bleeding in the brain.

Spinal taps also can be used to add medicine, anesthesia, or dye (for specialized X-rays) directly into the cerebrospinal fluid. Occasionally, they’re done to help relieve pressure in the brain when a condition causes the body to make too much CSF.

What Happens Before a Spinal Tap?

If your child needs a lumbar puncture, you’ll have an opportunity to ask questions first. Then, you’ll be asked to sign an informed consent form, stating that you understand the procedure and its risks and give your permission for it.

Most spinal taps are done in the emergency department. The doctor doing it will know your child’s

but might ask a few questions, such as whether your child is allergic to any medicines.

Some parents choose to be in the room with their child during the spinal tap, while others are more comfortable in a waiting area. You can ask the doctor if it is OK for you to stay.

What Happens During a Spinal Tap?

A spinal tap is a common procedure that takes about 30 minutes or less.

The spinal cord extends from the lower part of the brain down to the upper lumbar area. A spinal tap is done in the lower lumbar area, below the point where the spinal cord ends. So, the risk of harming the spinal cord is avoided.

A lumbar puncture is not a surgery. So someone getting one might be awake during it, and won’t need stitches or extended recovery time. If a child seems anxious or agitated, the doctor will recommend a sedative (a type of medicine that helps the patient relax during the procedure). The sedative can be given by mouth, nose, or through an IV.

Patients should be positioned with the back curved out so the spaces between the vertebrae are as wide as possible. This makes it easier for the doctor to insert the needle.

Older children may be asked to either sit on an exam table while leaning over with their head on a pillow or lie on their side. Infants and younger children are positioned on their sides with their knees under their chin. For these children, nurses or aides hold them securely in position.

When the patient is in position, a doctor will use sterilizing soap to clean the area where the needle will go in.


A small area on the lower back is numbed by a type of liquid anesthesia (medicine that helps prevent pain) given through a tiny needle. Often, a numbing cream is applied to the skin before this. The cream eases the discomfort of the injection, although the liquid medicine may burn a little.

The Spinal Needle

The spinal needle is the most important tool of this procedure, and functions as the “tap.” The needle is thin and the length varies with the size of the patient. It has a hollow core. Inside the hollow core is a “stylet,” another type of thin needle that acts kind of like a plug. When the spinal needle is inserted into the lower lumbar area, the stylet is carefully removed, letting the CSF drip into the collection tubes.

“Tapping” the Cerebrospinal Fluid

Making sure the patient is in the proper position, a doctor carefully inserts the spinal needle between two vertebrae. The needle is carefully passed through skin and ligaments, and then through a tough membrane called the dura mater. Doctors can tell that the needle is in the right place when they feel a “pop,” which means the needle passed through the tough membrane. When the needle reaches an area called the spinal canal, the stylet is slowly pulled out to allow the cerebrospinal fluid to flow.

Occasionally, a small tool called a manometer is hooked up to the end of the needle. A manometer is basically a gauge that measures pressure of the CSF. High fluid pressure can be an indicator of some serious conditions, like tumors or hydrocephalus (excessive buildup of fluid in the brain).

Collecting the CSF sample usually takes about 5 minutes. Then, the needle is withdrawn and a small bandage is placed on the site. Collected samples are sent to a lab for testing.

What Happens After a Spinal Tap?

If you were not in the room with your child during the test, you can come in after the samples have been collected. Depending on the doctor’s recommendations, your child might have to lie down on his or her back for an hour or so after the procedure.

Some results are available within 30 to 60 minutes. But to look for specific bacteria growing in the sample, a bacterial culture is sent to the lab. These results are usually available in 48 hours. If there might be an infection, the doctor will start antibiotic treatment while waiting for the culture results.

Lab technicians look for several things when examining the cerebrospinal fluid sample, including:

  • General appearance: CSF is usually clear and colorless like water. Cloudy spinal fluid or any blood in the sample may indicate an infection or other problem.
  • Cell count: This includes the number and type of white blood cells. Too many white cells indicate an infection.
  • Protein: Large amounts of protein in the CSF can suggest an infection or other diseases.
  • Glucose: In bacterial infections of the central nervous system, the glucose level of the CSF is sometimes low.

Lab technicians also do a Gram stain and culture on the sample. A Gram stain detects bacteria in a sample. This involves adding a kind of dye to it, then checking it for bacteria. Then the sample is cultured (put in special conditions to see if any germs grow from the CSF). This helps identify the specific type of infection.

What Are the Risks of a Spinal Tap?

A spinal tap is a safe procedure with few, if any, risks. Rarely, complications can include:

  • Headache: After a lumbar puncture, a patient should lie down for a few hours and drink plenty of fluids, which can help prevent a headache. Babies do not need to do this. If your child gets a headache, acetaminophen or another non-aspirin type of pain reliever usually helps. If a headache lasts for more than 2 days, call your doctor.
  • Infection: In rare cases, infection can happen if bacteria get into the skin when the puncture is done. This is very rare because doctors always use sterile techniques to do the test.
  • Bleeding: If a small blood vessel under the skin is nicked during the spinal tap, there may be some bleeding.

When your child is having any kind of procedure, it’s understandable to be a little uneasy. But it helps to know that spinal taps are brief, common procedures and complications are rare. If you have any questions or concerns, talk with your doctor.

Reviewed by: KidsHealth Medical Experts

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