Lumbar Puncture Consent 💉
Consent guide for lumbar puncture. Procedure explanation, risks, benefits, alternatives, and patient information for obtaining informed consent.
🔍 Procedure
- Lumbar Puncture – sampling of cerebrospinal fluid (CSF) from the lumbar thecal sac using a needle inserted between the lumbar vertebrae.
💡 Indications
- Suspected meningitis, encephalitis or subarachnoid haemorrhage
- Suspected demyelinating disorders (e.g. MS)
- Measurement of CSF opening pressure
- Therapeutic relief of raised intracranial pressure (in certain conditions)
🧾 Procedure Walkthrough
- Patient lies in a fetal position or sits upright leaning forward.
- Sterile technique used; local anaesthetic given to skin.
- A fine needle is inserted between L3–L5 into the subarachnoid space.
- CSF collected into bottles; opening pressure may be measured.
- Patient remains flat post-procedure to reduce risk of headache.
⚠️ Risks & Complications
- Common (10–30%): Post-LP headache, local discomfort or bruising
- Less Common (1–5%): Bleeding, infection at puncture site
- Rare (<1%): Nerve root irritation, back pain, cerebral herniation (if raised ICP)
💬 Common Patient Questions
- Will it hurt? — You may feel pressure or discomfort, but we use local anaesthetic.
- Can I move afterwards? — Yes, but you’ll be asked to lie flat for an hour or two.
- Will I get a headache? — Some people do, but it usually settles within 1–2 days.
- Is it safe? — Yes, in most people. We rule out raised pressure with a CT or fundoscopy first if needed.
✅ Benefits
- Can identify infection, inflammation or bleeding in the brain/spinal cord
- Helpful for diagnosis of neurological disease
- Relatively quick and minimally invasive diagnostic tool
🔄 Alternatives
- CT or MRI brain – no CSF sampling but useful for structural abnormalities
- Blood tests – limited value for diagnosing CNS infection or inflammation alone
- No investigation – not appropriate when serious CNS pathology is suspected
🧠 Special Considerations
- Check for signs of raised intracranial pressure – fundoscopy, CT brain if needed
- Check INR, platelets – correct coagulopathy or withhold anticoagulation as necessary
- Infection risk – ensure sterile technique and consider prophylactic antibiotics if needed
- Ensure consent, explanation, and reassurance – especially in anxious patients
🗣️ Example Consent Script
- "We’re recommending a lumbar puncture to check the fluid around your brain and spinal cord for signs of infection, bleeding, or inflammation."
- "The procedure involves inserting a needle into your lower back to collect fluid. You’ll be given local anaesthetic."
- "Risks include a headache, some discomfort, or rarely bleeding or infection. We’ll monitor you afterwards."
- "Do you have any questions before we proceed?"
External resources
Educational reference only. Medical disclaimer