Lumbar puncture


Allows for cerebrospinal fluid to be sampled to facilitate the diagnosis of meningitis, subarachnoid hemorrhage, demyelinating disease and leptomeningeal metastases.

Indications for the procedure: suspicion of meningitis, subarachnoid hemorrhage, suspicion of central nervous system diseases such as Guillain-Barré syndrome and carcinomatous meningitis, and to relieve symptoms of pseudotumor cerebr I.

LP commonly performed with diagnosis and treatment of CNS infections, neurological diseases and certain types of cancer.

Minimal platelet count recommended 30-50,000/m3 although these numbers have not been confirmed by clinical studies.

Should be performed only after a neurologic examination.

Proceure should never delay potentially life-saving interventions, such as the administration of antibiotics and steroids to patients with suspected bacterial meningitis.

Opening pressure at the time of lumbar puncture is normally 65-195 mm of water.

Numerous complications can occur but the most common being low CSF pressure headache, which occurs about 30% of the time using the conventional bevel-tipped needle.

Headache can occur in up to 60% of patients depending upon criteria and definitions of headache.

Headaches may be severe and result from leakage of CSF through the dural puncture site.

Backache can occur in up to 40% of patients.

Cerebral herniation, intracranial subdural hemorrhage, spinal epidural hemorrhage and infection are other rare adverse possibilities.

Risk of headache can be reduced to about 5% by using an atraumatic needle and replacing the stylet before withdrawing the needle.

In the presence of expanding masses such as brain abscess, necrotic temporal lobe in encephalitis, subdural empyemas, bacterial meningitis the withdrawal of CSF reduces counter pressure from below adding to effect of compression from pressure above increasing brain shift that may already be present.

Neuroimaging with either CT or MRI of the brain to detect brain shift is recommended in selected patients before lumbar puncture.

Contraindications include the presence of infected skin over the needle entry site, findings of unequal pressures between the supratentorial and infratentorial compartments.

Relative contraindications for lumbar puncture include increased intracranial pressure, coagulopathy, and brain abscess.

Indications for performing brain CT scanning before lumbar puncture in patients with suspected meningitis include: immunocompromised patients, patients over age 60 years, patients with known CNS lesions, patients with recent seizures, patients with altered level of consciousness, patients with neurological exam abnormalities, patients with papilledema, patients with suspected subarachnoid hemorrhage.

Dual platelet anti therapy may not pose a risk of increased complications (Carabenciov, ID).

Spinal hematoma may be caused by lumber puncture and presents with back pain, radiculopathy, urinary incontinence, and inferior paraparesis.
In a Danish study the overall 30 day risk of spinal hematoma was 0.2% among patients without a coagulopathy and 0.23% among patients with coagulopathy.

Leave a Reply

Your email address will not be published. Required fields are marked *