Surgeons and Neurologists use information obtained from a patient’s cerebrospinal fluid (CSF) to examine and rule out disease or infection in the brain and spinal cord. Such tests are called lumbar punctures, also referred to as a spinal tap.
Lumbar punctures need the doctor to insert a needle into the patient’s lower (lumbar) back and draw out a small amount of the cerebrospinal fluid for further testing. This procedure is done as needed on adults, elderly, children and infants. More times than not it is performed in an emergency room, hospital or clinic.
This procedure can also be used to determine if cancer cells are present within the fluid. In children it is generally used to diagnose meningitis. Doctors examine the fluid to diagnose other diseases such as encephalitis, causes of seizures, multiple sclerosis, cerebral malaria, tumors, with the possibility of helping to diagnose Alzheimer’s disease. Lumbar punctures help to determine if blood is present in the fluid. If blood is present it is a clear indicator of cerebral hemorrhaging.
Another reason why lumbar punctures are used is to remove excess cerebrospinal fluid where an infection is causing pressure to the brain or spinal cord.
Besides removing fluid from the brain and spinal cord, lumbar punctures provide a means to inject a patient with antibiotics and medicines for the specific ailment, such as with certain cancer patients.
Patients are expected to empty their bladders before undergoing the process. Then he is told to lay on his side with knees to stomach and chin to chest. A nurse will help the patient remain in this position as the area is cleaned, a sterile environment contained, anesthetic is administered and the test performed. A relaxed patient is recommended since tensing may contaminate the test by causing the needled to move and blood to form onto the needle.
There are some risks involved in lumbar punctures though side effects are considerably rare. Patients need to have a driver as they should never drive themselves home after the procedure. A local anesthetic is administered to the spinal cord before the actual puncture. Some patients experience headaches that may last up to five days before fading. Headaches that last longer than seven days should be reported to a doctor. Other side effects include infection, herniation, nerve injury, lower back pain, bleeding in the brain or spine, fainting and movement of the brain if there is abnormal pressure still existent. Patients experiencing any of these side effects need immediate treatment.
Patients requiring lumbar punctures should discuss the procedure, helpfulness and risks involved with their doctor or neurologist.