Lumbar puncture (LP) with examination of cerebrospinal fluid (CSF) is an important diagnostic tool for a variety of infectious and noninfectious neurologic conditions.
The techniques, indications, contraindications, and complications of LP in adults will be reviewed here. Technique of LP in children and for spinal and other types of neuraxial anesthesia is discussed separately.
Analysis of the CSF is discussed separately.
INDICATIONS
LP is essential or extremely useful in the diagnosis of bacterial, fungal, mycobacterial, and viral central nervous system (CNS) infections and, in certain settings, for help in the diagnosis of subarachnoid hemorrhage (SAH), CNS malignancies, demyelinating diseases, and Guillain-Barré syndrome.
CONTRAINDICATIONS
Although there are no absolute contraindications to performing the procedure, caution should be used in patients with:
●Possible raised intracranial pressure (ICP) with risk for cerebral herniation due to obstructive hydrocephalus, cerebral edema, or space-occupying lesion
●Thrombocytopenia or other bleeding diathesis, including ongoing anticoagulant therapy
●Suspected spinal epidural abscess
In many situations, high-risk patients can be identified and risks can be mitigated. These are discussed in detail in relation to the complications with which they are associated. (See ‘Complications’ below.)
When the LP is delayed or deferred in the setting of suspected bacterial meningitis, it is important to obtain blood cultures (which reveal the pathogen in more than half of patients) and promptly institute antibiotic therapy. Urgent evaluation and treatment of increased ICP, along with the administration of antibiotics and steroids, should be instituted promptly when this is suspected. Specific treatments are discussed separately.
