Lumbar Puncture Side Effects

Lumbar puncture is a diagnostic procedure employed for collecting a sample of cerebrospinal fluid or CSF, the fluid that surrounds the brain and the spinal cord. The cerebrospinal fluid is then tested for diagnosing a number of conditions including bacterial meningitis. Rarely, lumbar puncture is also used for therapeutic purposes, especially for injecting medications into cerebrospinal fluid in certain illnesses. Lumbar puncture is also known by the name of spinal tap lumbar puncture. Before discussing the spinal tap lumbar puncture side effects, let's have a brief look at the procedure and why it is carried out.

Procedure of Lumbar Puncture
Lumbar puncture typically involves the insertion of a needle between the third and fourth lumbar vertebrae, in order to collect cerebrospinal fluid. But, before inserting the needle, the patient is usually asked to lie down in a lateral position, with the neck and knees bent fully. The knees should be ideally bent up to the chest. Rarely, the procedure is also carried out with the patient sitting on a chair or stool, with his or her head and shoulder bent forward towards the knees. Local anesthesia is applied on the skin of the lumbar area, after which a needle is inserted between the appropriate lumbar vertebrae and pushed into the spinal canal to collect the cerebrospinal fluid. While collecting this fluid, a column manometer is used to measure the pressure of spinal fluid.

Why it is Performed?
Lumbar puncture is usually performed when meningitis is suspected, as it the most reliable tool for diagnosing this disease. Other than meningitis, medical conditions that can require lumbar puncture procedure include subarachnoid hemorrhage, hydrocephalus, benign intracranial hypertension, tumor, multiple scelrosis and other diseases of the brain and spinal cord. Diagnosis of these diseases are mainly carried out on the basis of the pressure of the cerebrospinal fluid, and the presence of blood cells in it, especially, the white blood cells like granulocytes. Occasionally, lumbar puncture or spinal tap lumbar puncture is also used for administering certain medications like cancer drugs, antibiotics, etc., into the cerebrospinal fluid. It is also employed for removing spinal fluid in conditions like hydrocephalus, and benign intracranial hypertension in order to reduce spinal fluid pressure.

Lumbar Puncture Side Effects
Lumbar puncture is by and large, a safe procedure; serious side effects being very rare. The most commonly encountered side effect of lumbar puncture is headache, that usually lasts for two to three days. This can be relieved by regular analgesics or pain killers. But, if the headache persists for several days, and occurs when sitting up, then it can be an indicator of cerebrospinal fluid leak. If the condition does go away with enough bed rest, then physicians can treat it with epidural blood patch. In this method, patient's own blood is injected into the site of the leakage, so that the blood clot formed could seal off the leakage.

Headaches caused by lumbar puncture are generally felt either at the front of the head or near the base of the skull and is experienced by about 40% of people who have gone through the procedure. Apart from headaches, a few patients (approximately 1 in a population of 1000) can get minor nerve injury. As has been mentioned above, serious lumbar puncture side effects are very rare. Such serious complications can include spinal or epidural bleeding, and trauma or injury to the spinal cord or spinal nerve roots and paraplegia or paralysis of the lower half of the body. Injury or trauma to the spinal cord or spinal nerve can result in loss of sensation. Tonsillar herniation, cranial neuropathies, spinal hematomas, vasovagal syncope, subarachnoid cysts and seizures are some other rare lumbar puncture side effects. Back pain, especially on the lower part is however, not so uncommon.

Considering the lumbar puncture side effects, especially the more serious ones, the procedure is not recommended for those having epidural infection, bleeding problems, brain tumor and infection and bleeding inside the brain. The procedure is also not recommended for those taking blood thinning medications. Conditions like brain tumor, infection or bleeding in the brain raises the pressure inside the brain, which can lead to some serious side effects. Therefore, physicians usually examine the entire nervous system including brain and spinal cord before performing lumbar puncture. Many times, CT scan and MRI of the brain is done to decide whether lumbar puncture can be done safely. Thus, the physicians carry out a complete analysis and evaluation of a patient's health condition, before opting for lumbar puncture procedure, which is generally recommended only in the case of potentially serious medical conditions.