Lumbar Puncture: What to Expect
Answering the three most common questions for MS patients about an LP procedure.
When I tell my patients that I feel they are going to need an LP, they are naturally full of many questions. Let me answer the three most common questions here.
- Will it hurt? It might. Where I practice, we are spoiled in having radiologists perform the procedure. They are able to use imaging to help guide the needle right where it needs to go. In most offices however, the LP is performed at the bedside by a neurologist who guides the needle by feel alone. In all cases, a local anesthetic will be applied to numb the area. Naturally, the ease of this depends on the experience of the neurologist and the body size of the person undergoing the procedure. In my experience, there is a huge range of how people tolerate the procedure. I had one patient fall asleep during what is usually the most painful part, while other patients have screamed in pain when I washed their back! The procedure does involve a needle being placed into someone’s back, so most people can expect some degree of pain. If someone is terrified about having an LP, they can request a mild sedative such as Valium to help them better tolerate the procedure.
- Is it dangerous? In a word: no. When done properly, there is no risk for any serious complication, such as paralysis, from an LP. The procedure does have to be done in a sterile fashion to minimize the risk of infection. This does not mean that it has to be done in a sterile operating room, however. An LP should not be performed on someone with disordered blood clotting.
- What are the risks? There are only two real risks from having an LP. The first, as discussed above, is pain from the actual procedure. The second is that a minority of patients develop a headache after the procedure. This headache, while not serious, can be extraordinarily painful. It is termed a positional headache in that the headache lessens when people lie down, but returns with a vengeance when people stand up. Fortunately, there is a simple cure for this, called a blood patch. Like a lumbar puncture, this sounds worse than it actually is. In a blood patch, a doctor will inject a patient’s own blood at the same location as the original LP. This procedure is highly effective in almost all patients in permanently eliminating the headache.
Fortunately, an LP is a procedure that someone with a possible diagnosis of MS needs only once. It usually takes about 30 minutes from start to finish, and patients can leave as soon as it is over, though they are advised to relax for the rest of the day. So, while it can be painful and scary, it should not be viewed as a “major procedure” or something that carries significant risk of permanent damage.
I am available via e-mail address at firstname.lastname@example.org and will try to answer all questions.