LP involves inserting a small needle between the vertebrae below
the base of spinal cord. A small amount of fluid is collected. There
is no risk for paralysis.
What is a lumbar puncture?
Lumbar Puncture (LP), also called a spinal
tap, is a procedure used to obtain a sample of cerebrospinal fluid (the
fluid that surrounds the brain and spinal cord) for testing and/or pressure
measurements. When performed by an experienced practitioner, the LP is
safe and involves minimal risks or discomfort.
Is there any preparation for an LP?
You need to inform your physician
if you are on any blood thinning medications (such as Coumadin, Plavix,
or Aggrenox). You will be asked to stop taking these medications for
72 hours prior to the LP. You may also be asked to increase your fluid
intake the day before (no alcohol). Have a light meal the morning of
your LP and wear loose fitting clothing to the office.
How is the LP performed?
You will be asked to sit on the edge of the
exam table, in a hunched forward position by hugging a pillow OR you
will lie on your side with your knees drawn up toward your chin. Your
lower back will be scrubbed with a Betadine cleaning solution (let us
know if you have any allergies to iodine). A local anesthetic medication
is then injected into the skin to numb the site. The initial injection
of the anesthetic stings for a brief moment - we will inform you when
you will feel this so that you hold as still as possible. When the skin
is numb, a small spinal needle is inserted into the back at the level
of your waist. The spinal cord ends just above this level so there is
no risk of injury to the spinal cord. The needle is passed gently between
(not through) the bones of the spine until the spinal fluid is found.
Approximately 3-4 tablespoons of fluid are removed and put into sterile
Are there risks involved?
You may experience minor pain, bruising or
swelling of the skin where the needle was inserted. A post LP headache
can also occur. Less than 10% of those having an LP report a headache.
These headaches are usually mild and last 0-2 days and rarely may last
as long as a week. More severe headaches or headaches lasting longer
than a week may require an additional procedure called a "Blood
Persons who faint or feel nauseous when having their blood
drawn may have a similar flushing/fainting experience in response to
an LP. All precautions are taken to anticipate these potential problems
and minimize these risks. A very rare occurrence is infection from the
tap itself; the risk for such infection is less than that of a regular
What should I do after the procedure?
You will have a small band-aid
covering the site, which you can leave on for a couple of hours. You
may be asked to rest in office for 30 - 60 minutes and given fluids to
drink. Continue to drink plenty of fluids (except alcohol), during the
next 12 hours. Avoid heavy lifting and strenuous physical activity for
24 - 48 hours.
What should I do if I do get a headache?
The cause of the headache is
leakage of spinal fluid around the puncture site. It will be important
for you to lie down and keep your head flat. Only move in a slow manner
- no jerking your head which can increase your headache, and no straining
your back which may further cause a leak. Continue to drink plenty of
fluids - caffeinated beverages (coffee, tea & colas) seem to ward
off as well as help with spinal headaches. Mild analgesics like Tylenol,
Ibuprofen or Aleve are suggested. You may also find ice packs to your
forehead or back of neck helpful.
Low back discomfort is also relieved with rest; mild analgesics and
a heating pad may also be used.
If you have any questions or concerns, please don't hesitate to contact
our physicians at (602) 258-3354 or Kathie Clarke RN, MS, CNS - BC Neuroscience
Clinical Nurse Specialist, can be reached at EXT: 125.