A lumbar puncture is a procedure of withdrawing a sample of cerebrospinal fluid (CSF), which surrounds the brain and the spinal cord. It is basically a diagnostic procedure, although it is also employed for therapeutic purposes at times.
The entire procedure involves the insertion of a needle between the third and the fourth lumbar vertebrae, in order to collect a sample of CSF. The needle is pushed into the spinal canal to draw out a small amount of CSF. Ideally, the patient has to lie down in a lateral position with the neck and the knees bent in full flexion, or he or she has to sit with the head and the shoulder bent forward towards the knee. This procedure is also known by the name of spinal tap.
Uses of Lumbar Puncture
It is the most dependable diagnostic test for meningitis, which is characterized by the inflammation of the tissues that surround the brain and the spinal cord. These tissues are known as meninges. The inflammation of the meninges are caused by bacteria. While collecting a sample of the cerebrospinal fluid, a column manometer is used to measure the pressure of the fluid.
The sample of CSF is examined for the presence of blood cells, especially the white blood cells. A number of diseases can be diagnosed with this procedure depending on the result of the examination and the pressure of the spinal fluid. This procedure is mainly employed for diagnosing diseases like hydrocephalus, benign intracranial hypertension, subarachnoid hemorrhage, brain tumors, and the diseases of the brain and the spinal cord like multiple sclerosis.
As mentioned already, this procedure is also used for therapeutic purposes. It is usually employed for injecting medications and anesthetic agents into the cerebrospinal fluid. The medications that are administered with this method are cancer drugs and antibiotics. Occasionally, this procedure is also used to drain spinal fluid, if its pressure increases significantly. This may be the case with diseases like benign intracranial hypertension and hydrocephalus.
Lumbar Puncture Dangers
Despite being a very important diagnostic tool, this procedure is not without its share of complications and side effects. However, if properly carried out, serious side effects are quite rare. Therefore, a spinal tap is generally considered a safe procedure that can be used to collect cerebrospinal fluid, and administer medications into this fluid, in order to treat certain diseases. Nevertheless, the following are some common problems or side effects associated with this procedure.
Headaches are one of the most common complications, which can affect about 40% individuals undergoing this procedure. The pain is usually experienced near the base of the skull or at the front of the head. Such headaches usually resolve within a few days. In the meantime, pain killers or analgesics can be used to relieve the pain, after discussing the issue with a physician.
Cerebrospinal Fluid Leakage
Headaches persisting for several days that do not go away with bed rest can be an indicator of cerebrospinal fluid leakage, which can take place while collecting a sample of the fluid. Such a situation can necessitate treatment with epidural blood patch, where a small amount of blood is injected into the site of the leakage. The blood clots formed help seal off the leakage caused by this procedure.
Back Pain and Nerve Injury
Back pain can also be experienced by some individuals after the procedure. The pain is usually felt in the lower back region. In addition to these, nerve injuries can affect about 1 in 1000 people undergoing this procedure. However, such nerve injuries are usually not of severe nature.
A trauma or injury to the spinal cord or the spinal nerve roots can be termed as one of the serious complications associated with this diagnostic procedure. Sometimes, spinal or epidural bleeding, as well as paraplegia or paralysis of the lower half of the body can also take place. Apart from these, spinal hematomas, subarachnoid cysts, cranial neuropathies, and seizures are some other less common complications associated with a lumbar puncture.
The major complications associated with the spinal tap are more likely to be experienced by patients who have been suffering from conditions like bleeding problems, brain tumors, epidural infections, and bleeding inside the brain. Therefore, this procedure is not recommended for such individuals. It is also not recommended for individuals taking blood thinning medications.
So, the major complications associated with the spinal tap usually develop in patients who have some serious underlying health conditions. Therefore, physicians usually examine and analyze the nervous system and the overall health condition of the patient, before performing a spinal tap or lumbar puncture. This helps them decide if the procedure can be done safely without giving rise to any major complications.
Disclaimer: This HealthHearty article is for informative purposes only, and should not be replaced for the advice of a medical professional.