Lumbar puncture: its functions, procedures and preparation

Lumbar puncture is a test performed for diseases related to the brain and spinal nervous system. The procedure is performed by taking cerebrospinal fluid (CSF) which is present in the protective membrane of the central nervous system. A number of cerebrospinal fluid will be taken through a needle that is injected into the lower part of the spine (lumbar area) for further analysis in the laboratory.

Usefulness of lumbar puncture examination

Lumbar puncture aims to collect cerebrospinal fluid (CSF) samples in the spine. The cerebrospinal fluid is the lining of the meninges that protects the brain and spinal cord. This CSF functions to maintain the balance of the nervous system.

This method is generally effective in diagnosing diseases affecting the brain and spinal cord systems. Lumbar puncture can be performed when the disease is not known at all or to find out the cause of a certain disease.

So far, lumbar puncture has been the main test to diagnose meningitis. Through this method, not only can meningitis be detected, but the cause of meningitis can also be identified with certainty.

According to John Hopskin Medicine, several conditions and diseases that can be diagnosed through lumbar puncture include:

• Meningitis or inflammation of the protective membranes of the brain and spinal cord
• Severe headache with no known exact cause
• Inflammation of the brain (encephalitis)
• A condition characterized by increased pressure on the brain
• Diseases caused by inflammation of the nervous system, such as multiple sclerosis and Gullain-Barre's syndrome
• Cancer or tumors that attack the brain and spinal cord
• Leukemia
• Inflammation of the spinal nervous system (myelitis)
• Alzheimer's disease and other conditions associated with decreased nervous system function
• Neurosyphilis, which is syphilis that has attacked the nervous system

If you experience symptoms of meningitis, such as fever, headache, stiff neck or other disorders from the above diseases, you will need to undergo a lumbar puncture to determine the cause.

Lumbar puncture for treatment

Apart from diagnosing diseases, lumbar puncture can also serve as a medical treatment. Some medical conditions that can be optimally treated with the help of spinal fluid collection include:

• Knowing the level of cerebrospinal fluid pressure in the spinal cord and brain.
• Reduces pressure on the spine and brain
• Inject drugs directly into the nervous system, such as chemotherapy drugs, antibiotics, or anesthetics.
• Inject dye and radioactive substances to obtain diagnostic images for certain neurological conditions.

Risks of lumbar puncture examination

Although this procedure is generally quite safe to perform, there are a number of side effects and complications that may arise. The reason is, lumbar puncture involves the brain and spinal nervous system so that it tends to cause several disorders.

The risks and side effects of the lumbar puncture procedure include:

• Headache due to a small amount of cerebrospinal fluid leaking when the needle is injected
• Nausea and vomiting
• Feet and back feel numb or numb
• Pain or aches from the back to the feet
• Risk of infection in the skin due to needles
• Risk of bleeding around the spinal cord

There may also be other risks depending on your health condition. Therefore, make sure you always consult your doctor or medical personnel before performing this procedure.

What preparations need to be made?

Before a lumbar puncture is performed, you are usually asked to undergo several other medical tests. As in the examination of meningitis, the doctor will first perform a physical examination, blood tests, and a CT scan or MRI to determine the location of the inflammation.

Some of the things you need to prepare before undergoing a lumbar puncture include:

• Increase fluid intake by drinking water or juice, unless it is not recommended by a doctor or health worker because it is related to health conditions.
• On the day of the procedure, you must not eat 3 hours before the lumbar puncture is performed.
• You should arrive at the hospital 1 hour before the procedure. Next, you will be asked to change clothes and remove the jewelry used.

In addition, you also need to inform about your health condition and current medication before carrying out procedures, such as:

• Take antibiotics to stop the infection. If you have fever, the lumbar puncture will be postponed until you recover.
• Have an allergy to certain anesthetics, such as lidocaine. The doctor can change the anesthetic that is injected before a lumbar puncture is performed to prevent an allergic reaction.
• Take blood thinners, such as warfarin, clopidogrel or pain relievers such as aspirin and ibuprofen. This medicine can cause side effects of bleeding when the procedure is carried out so you need to stop taking it temporarily.
• Are pregnant or in a pregnancy program. You need to consult a doctor to consider the risks that may occur.

How is the lumbar puncture process done?

Lumbar puncture is usually performed in a hospital or other health facility by a neurologist and nurse. The procedure for taking CSF from the spine will generally take 45 minutes to 1 hour.

To prevent the needle from going too far, a radiographic scan will also be performed via a fluoroscopy procedure using X-ray radiation.

The following are the steps for examining a lumbar puncture:

• You will be asked to sit with your chin close to your chest and your knees in front of your stomach so that the space in your spine becomes wider.
• A local anesthetic or anesthetic will be injected into the lower back. The anesthetic injection will indeed sting for a while, but it will reduce the pain when a lumbar puncture is performed.
• The doctor will inject a thin, hollow needle into the lower back, which is in the spine or lumbar area.
• The needle will continue to enter until it reaches the target point. During this procedure, you may feel pressure in your back.
• You will be asked to change position slightly so that the needle can draw in the cerebrospinal fluid (CSF). The doctor will measure the pressure inside the lumbar area.
• The steps taken will depend on the purpose of the lumbar puncture examination. To diagnose meningitis, the doctor will take a CSF sample with a needle. Meanwhile, for treatment, the drug will be inserted through the needle.
• After the procedure, the needle is removed and the injection point is covered with a bandage.

Post-examination recovery

As long as the needle is injected, you will feel uncomfortable. After the procedure is done, the nurse will ask you to lie down to help relieve headaches from the effects of the procedure. You also need to increase your fluid intake again.

For a more optimal recovery, you need to rest completely after the procedure, for at least 1 day. You can stay overnight or return home, but make sure you don't do strenuous physical activity.

If needed, you can take pain relievers, such as ibuprofen or paracetamol to treat the side effects of headaches and back pain. However, you need to contact your doctor immediately if side effects occur, such as:

• Numbness or frequent tingling of the feet
• Bleeding at the point of injection
• Difficulty urinating
• Headaches that don't go away

Results of lumbar puncture examination

The CSF sample taken will be analyzed in the laboratory. Results generally last 1-2 days, but may take longer.

The results of the laboratory analysis will also be combined with the results of the pressure tests during the procedure. Reporting from the Mayo Clinic, some things that can be found out from the results of a lumbar puncture examination are:

• Cerebrospinal conditionsl: If normal, the liquid is colorless. Yellowish and reddish color may indicate bleeding. Meanwhile, the color of the liquid that is green or bluish can indicate an infection or the content of bilirubin.
• Protein: A protein level of more than 45 mg / dL can indicate infection or inflammation.
• White blood cell: CSF normally contains 5 leukocytes per microliter. A higher number can indicate an infection.
• Sugar: Low blood sugar levels can indicate infection.
• Microorganisms: The presence of certain microorganisms, such as bacteria, viruses, or parasites can determine the cause of infection or inflammation.
• Cancer cells: The sample can show the presence of tumor cells in the CSF that could indicate certain types of cancer.

Lumbar puncture has many uses in the diagnosis, examination of diseases affecting the central nervous system, and in medical treatment. Although it can cause pain, discomfort and certain side effects, it is a fairly safe procedure to do.

Make sure you discuss with your doctor the risks and benefits as clearly as possible to find out your best option.