Lumbar puncture (spinal tap)
Is a sterile procedure in which a spinal needle is inserted, between the third
and fourth lumbar vertebrae in the lower spine at the subarachnoid space i.e. the space between the
spinal cord and its covering, the meninges to obtain samples of cerebrospinal
fluid (CSF) for qualitative analysis.
Indications of Lumbar puncture
- Measure cerebrospinal fluid (CSF) pressure
- Assist in the diagnosis of suspected CNS infections (bacterial or viral meningitis,
meningoencephalitis), intracranial or subarachnoid hemorrhage, and some malignant disorders
- Evaluate and diagnose demyelinating or inflammatory CNS processes such as Multiple Sclerosis,
Guillan-Barré Syndrome (GBS), Acute Disseminated Encephalomyelitis (ADEM)
- Infuse medications which include spinal anesthesia before surgery, contrast material for
diagnostic imaging such as Inject dye (myelography), radioactive substances
(cisternography) and chemotherapy drugs directly into the spinal
- Treat normal pressure hydrocephalus, cerebrospinal fistulas, and idiopathic intracranial
- Placement of a lumbar CSF drainage catheter
- Space occupying lesion: A computerized tomography (CT) scan or MRI prior to a lumbar puncture can be
obtained to determine if there is evidence of a space-occupying lesion that results in
increased intracranial pressure.
- Severe coagulopathy: Due to the significant risk of epidural hematoma formation.
- Severe degenerative vertebral joint disease: There will be difficulty in passing the needle through
the degenerated arthritic inter-spinal space.
- Skin infection near the puncture site: The presence of skin infection near the site of the lumbar
puncture increases the risk of contamination of infected material into the CSF.
- Increased intracranial pressure due to a brain tumor: Cerebral or cerebellar herniation with
severe neurological deterioration may occur after the withdrawal of CSF fluid.
> Receiver containing sponge holding forceps, dissecting and artery forceps.2 spinal
> Gallipot for antiseptic lotion
> Gallipot for sterile cotton swabs
> Gallipot for sterile gauze swabs.
> 5ml syringe for adm of Local anesthesia
> Sterile specimen bottles.
> A pair of sterile gloves.
> Drs. Gown, sterile drapers
> Manometer for measuring CSF pressure.
A tray with:
> Antiseptic lotion in a bottle
> Adhesive tape and scissor
> Lab forms
> Receiver for used swabs
> Sterile normal saline
At bed side:
> Bed pan and urinal
Before the procedure
- Explain the procedure to the patient. Explain to the patient the purpose of lumbar puncture, how
and where it’s done, and who will perform the procedure.
- Obtain informed consent. Make sure the patient has signed a consent form if required by the
- Reinforce diet. Advise the patient that fasting is not required.
- Promote comfort. Instruct the patient to empty the bladder and bowel before the procedure.
- Establish a baseline assessment data. Do vital signs monitoring and neurologic assessment of the
legs by assessing the patient’s movement, strength, and sensation.
- Place the client in a lateral decubitus position. Assist the client to assume a lateral decubitus
(fetal) position, near the side of the bed with the neck, hips, and knees drawn up to the chest. An
alternative position is to have the patient sit on the edge of the bed while leaning over a bedside
- Instruct to remain still. Explain that he or she must lie very still throughout the procedure. Any
unnecessary movement may cause traumatic injury.
During the procedure
- Arrange the equipment for use as per doctors convenience.
- Protect the bed using mackintosh and draw sheet.
- Position the patient for easy access.
- Provide a stool for the Dr.to sit on during the procedure.
- Expose the site to be punctured
- Help the in monitoring the patient’s condition.
- Maintain patients position.
- Reassure the patient to keep calm during the procedure.
- Apply brief pressure to the puncture site. Pressure will be applied to avoid bleeding, and the site
is covered by a small occlusive dressing or band-aid.
- Place the patient flat on bed. The patient remains flat on bed for 4 to 6 hours depending on the
physician. He or she may turn from side to side as long as the head is not elevated.
- Monitor vital signs, neurologic status, and intake and output. Take vital signs, measure intake and
output, and assess neurologic status at least every 4 hours for 24 hours to allow further
evaluation of the patient’s condition.
- Monitor the puncture site for signs of CSF leakage and drainage of blood. Signs of CSF leakage
includes positional headaches, nausea and vomiting, neck stiffness, photophobia (sensitivity to
light), sense of imbalance, tinnitus (ringing in the ear), and phonophobia (sensitivity to sound).
- Encourage increased fluid intake. An increased amount of fluid intake (up to 3,000 ml in 24 hours)
will replace CSF removed during the lumbar puncture.
- Label and number the specimen tube correctly. Ensure all samples are properly labeled and sent
to the laboratory immediately for further evaluations.
- Administer analgesia as ordered. Headaches after the procedure can last for a few hours or days
and is usually treated with analgesics
Normal Results of Lumbar puncture
- Pressure: 70 to 180 mm H20.
- Appearance: CSF is normally clear and colorless.
- CSF total protein: 15-45 mg/dL
- Gamma globulin: 3 to 12% of the total protein
- CSF glucose: 50 to 80 mg/dl
- CSF cell count: Normal CSF contains no red blood cells (RBCs), the white blood cell (WBC) count
is 0-5 WBCs per microliter (all mononuclear)
- CSF Chloride: 118 to 130 mEq/L
Procedure of Lumbar puncture
- Position the patient to fetal position: The patient is positioned on his side at the edge of the
bed with his knees drawn up to his abdomen and chin tucked against his chest (fetal position) or
sitting while leaning over a bedside table. When the patient is positioned supine, pillows are
provided to support the spine on a horizontal plane.
- Sterilize site of insertion: The skin is site is prepared and draped, and a local anesthetic is
- Insert the spinal needle: The spinal needle is inserted in the midline between the spinous
processes of the vertebrae (usually between the third fourth or the fourth and fifth lumbar
- Remove the stylet from the needle: The stylet is removed from the needle. CSF will drip out of
the needle if it’s properly positioned. A stopcock and manometer are attached to the needle to
measure the initial (opening) CSF pressure.
- Collect specimen: Specimens are collected and placed in the appropriate containers.
- Remove the needle: The needle is removed, and a small sterile dressing is applied.
Complications of lumber puncture
- Post-lumbar puncture headache. Around 25% of people who have undergone a lumbar
puncture develop a headache afterward due to a leak of fluid into nearby tissues.
- Back discomfort or pain.
- Bleeding. Bleeding may occur near the puncture site or, rarely, into the epidural space.
- Brainstem herniation. Increased pressure within the skull (intracranial), due to a brain tumor
or other space-occupying lesion
Prevention of post lumber puncture headache.
- Avoid strong light. Darkened room preferably.
- Give plenty of fluids to stabilize CSF level.
- Give analgesics
- Raise the foot of the Bed-Trendelenburg position.