Lumbar Puncture (Perform)
A lumbar puncture is performed for access to the subarachnoid space to obtain a cerebrospinal fluid sample, measure cerebrospinal fluid pressure, drain cerebrospinal fluid, infuse medications or contrast agents, or place a cerebrospinal fluid drainage catheter.1–3,7
PREREQUISITE NURSING KNOWLEDGE
• Knowledge of the anatomy and physiology of the vertebral column, spinal meninges, and cerebrospinal fluid (CSF) circulation, including the location of the lumbar cistern, is needed.
• Technical and clinical competence in performing lumbar punctures (LPs) is necessary.
• Knowledge of sterile technique is needed.
• The presence of meningeal irritation caused by either infectious meningitis or subarachnoid hemorrhage may promote discomfort when the patient is placed in the flexed, lateral decubitus position for the LP.3–5,17
• Computed tomography (CT) scan or magnetic resonance imaging (MRI) supersedes the routine use of LP for many diagnoses.5,7,18,28
• Indications for LP include the following4,5,18,28:
Suspected central nervous system (CNS) infection
Clinical examination results suggestive of subarachnoid hemorrhage accompanied by negative CT scan findings
Suspected Guillain-Barré syndrome
Intrathecal administration of medications
Imaging procedures that require infusion of contrast agents
CSF drainage in hydrocephalus, pseudotumor cerebri, or CSF fistula
• Contraindications for LP include the following3,18,28,29:
Increased intracranial pressure with mass effect
Superficial skin infection localized to the site of entry
Bleeding diathesis (relative contraindication)
Platelet count less than 50,000/mm3
• Normal CSF values include the following18,20,23,28:
Opening pressure, 0 to 15 mm Hg
White blood cell count, less than 5/mm