The lumbar puncture

The lumbar puncture, or "LP", is a frequently performed procedure in emergency departments, neurology and radiology clinics and hospital wards. In the emergency department, LP can yield information that can rapidly differentiate benign from emergent conditions.

In general, an LP may be done to:
  1. analyse the cerebrospinal fluid (CSF)
  2. measure the CSF pressure
  3. access the intrathecal space for either drainage of CSF or injection of fluid or to administer medications into the intrathecal space
  4. to perform myelography
The most common emergency department indications for a LP include clinical suspicion of meningitis (bacterial, viral or fungal) or to rule out subarachnoid hemorrhage.

Major contra-indications to lumbar puncture are:
  • symptoms or signs of raised intracranial pressure. These include a decreased level of consciousness, localizing (focal) neurologic signs and papilledema. LP in patients with raised ICP may lead to uncal herniation and death,
  • a severe bleeding diathesis or coagulation disorder or the patient is on anticoagulation therapy,
  • infection at the planned site of the puncture