A lumbar puncture is a procedure for taking spinal fluid and brain (cerebrospinal) fluid. This procedure is performed by inserting a needle into the spinal gap in the lower back.
The lumbar puncture procedure is usually used to check for diseases of the brain and spinal cord, such as meningitis or multiple sclerosis. This procedure may also be performed to insert medication directly into the brain or spinal cord.
LP can be performed on older persons, infants, and children. However, patients who are pregnant, allergic to anesthetics, or who are taking certain medications, such as blood thinners, need to inform their doctor before performing this procedure.
Lumbar Puncture Indication and Purposes
The lumbar puncture procedure can be performed as a method of diagnosis or treatment. The following are some of the purposes of this procedure:
- Taking a sample of cerebrospinal fluid to detect a disease
- Seeing the pressure in the cavity of the head and spine
- Administration of drugs in the nervous system, such as anesthetics or chemotherapy drugs
- Inserting a dye or radioactive substance into the cerebrospinal fluid before performing the scan
Cerebrospinal fluid sample examination
Examination of samples of brain fluid and spinal cord (cerebrospinal fluid) through a lumbar puncture aims to detect abnormalities in the nervous system, such as infection, bleeding, or cancer. Some diseases that may require a lumbar puncture as a method of diagnosis are:
Precautions Before Performing a Lumbar Puncture
Before a lumbar puncture is performed, the patient needs to inform the doctor if he is or has ever had a blood clotting disorder. This is so doctors can anticipate complications that may occur.
Please note, the doctor will give anesthesia before performing a lumbar puncture. Therefore, the patient also needs to tell the doctor if he has an allergy to certain anesthetic drugs, to prevent an allergic reaction to medicine.
Patients also need to tell their doctor if they are taking blood-thinning medications, such as aspirin or warfarin, because it can cause bleeding when a lumbar puncture is performed. Usually, the doctor will ask the patient to stop taking the drug a few days before the procedure.
Lumbar puncture preparation
During the initial examination, the doctor will ask the patient’s medical history and perform a physical examination. The doctor will also perform several supporting examinations, such as blood tests, CT scans, or MRI, if needed.
Other things the patient needs to do are:
- Drink more water for 2 days before the lumbar puncture procedure is done
- Fasting for 3 hours before the procedure, but still allowed to drink water
- Ask friends or family to accompany you, because the patient is not allowed to drive a vehicle or use public transportation alone for 24 hours after the procedure is performed
- Make sure to arrive at the hospital 1 hour before the procedure
- Change clothes with the medical gown provided and remove all jewelry and accessories worn
Lumbar puncture procedure
The following are the steps involved in the lumbar puncture procedure and procedure:
Positioning the patient during the lumbar puncture procedure
The patient will be asked to go up to the examination table and lie on his side, chin to chest, and knees to stomach.
The patient can also sit with the body leaning forward or hugging a pillow. This position will make the space between the spine becomes wider.
Anesthesia in the lower back
Before injecting the anesthetic, the patient’s lower back will be cleaned with an antiseptic solution and covered with a sterile cloth.
Next, the doctor will inject a local anesthetic into the lower back, to numb the area of the body where the needle will be inserted. The anesthetic injection will sting, but can provide some pain relief during the lumbar puncture procedure.
The neurologist will insert a needle into the spinal gap in the lower back. During the process, the patient should not move. After the needle is inserted to the desired level, the patient will be asked to change position so that the cerebrospinal fluid and spinal cord can exit.
The next course of action depends on the purpose of the lumbar puncture. The doctor can measure the pressure inside the spinal cavity, take a sample of fluid, or inject the medication. After that, the needle will be removed and the injection hole will be covered with a bandage.
This procedure usually lasts 30–45 minutes. Although there is no pain during the procedure, the patient will feel a sensation of discomfort and pressure in the back during the needle insertion process.
The results of the lumbar puncture can usually be known 48 hours after the procedure.
Recovery After Lumbar Puncture
After the procedure is complete, the patient will be asked to lie down for at least 1 hour under the supervision of a doctor. The patient may move as long as the head is not lifted from the bed. Usually, the patient has to use the bedpan to urinate.
The bandage used to cover the injection hole should not be removed in 24 hours after the procedure. The patient will be allowed to go home the same day after his condition improves. On the other hand, intensive care is required if the patient suffers from diseases such as: encephalitis.
Patients will also be advised to:
- Avoid strenuous activity for 24 hours after the procedure
- Not working, unless the job does not require moving too much
- Drink more water to reduce the headache risk.
- Drink caffeine-containing drinks, such as tea, coffee, or soda, to help relieve headaches
- Taking pain relievers that contain paracetamol to reduce pain in the head and back, according to the rules of use
Complications and Side Effects of Lumbar Puncture
In general, a lumbar puncture is safe to perform. However, this procedure can also cause complications, such as:
- Discomfort or pain in the back
- Bleeding at the injection site
- Skin infections
- Difficult to urinate
- Numb or tingling in the legs
Dangerous and fatal side effects, such as rupture of blood vessels and displacement of the brainstem, can also occur. However, these complications are very rare.
- Image: BruceBlaus. When using this image in external sources it can be cited as:Blausen.com staff (2014). “Medical gallery of Blausen Medical 2014”. WikiJournal of Medicine 1 (2). DOI:10.15347/wjm/2014.010. ISSN 2002-4436., CC BY 3.0 https://creativecommons.org/licenses/by/3.0, via Wikimedia Commons.
- Video: Design Science
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