Position the patient

Sitting or lateral foetal position

Identify the L4/L5 Intervertebral Space

In the midline between iliac crests

Mark the Desired Site

L3/L4, L4/L5, L5/S1

Using the marking pen

Prepare Sterile Field

Prepare Sterile Equipment

Place everything in the order it will be used

Prepare the Area

Decontaminate with chlorhexidine or povidone-iodine

Reposition the Patient

To ensure maximum flexion of the lumbar spine

Identify the Site Again

Maintaining sterile conditions

Inject Local Anaesthetic

Make a small wheal over the insertion site

Insert the Needle into the Midline

Slowly, with bevel up and facing slightly superiorly

A 'pop' may be felt on entry to the dura

Remove the Stylet

Look for CSF drainage

Collect CSF

Drain three 2mL  samples into specimen containers

Remove the Needle

Apply the Dressing

Clean Up

Dispose of sharps and other waste

Processing

Label the collection tubes and send to the lab

Bed Rest

Check local guidelines for bed rest post LP

Inadequate Sample

Blood-stained, insufficient volume

Back Pain

Bleeding

Around site or into the subarachnoid space

Infection

Meningitis, abscess