We often do lumbar puncture in the ED. Patients get warned about the potential of a post LP headache.

What is the prevalence of a post-LP headache?

The literature reports 15% of ED patients have a post LP headache.

How bad is it?

Most present in 3-7 days. Since the pain is postural, it impairs the patient’s ability to perform activities of daily living (imagine trying to do everything lying down in bed!). Slim women aged 18-40 seem to be at the highest risk.

What will decrease incidence of post LP headache?

Pick the correct spinal needle.

The incidence of post LP headache

  • 20G cutting needle: 40%
  • 25G cutting needle: 5%
  • 22G atraumatic needle (smaller dural puncture, smaller CSF leak): 4%.

Trick of the Trade

22G or 25G atraumatic spinal needle

The atraumatic spinal needles, also known as Sprotte needles, have a more blunt tip and often require a larger gauge needle to first puncture the skin. If using a 25G needle (which is a bit flimsy), I use a regular 18G needle to puncture the skin and soft tissue first (acting as a trocar), then I thread the 25G spinal needle through.





Stella Yiu, MD

Stella Yiu, MD

ALiEM Blog Contributor
Assistant Professor, University of Ottawa Staff Physician, The Ottawa Hospital
Stella Yiu, MD


Emergency physician and clinician educator in Ottawa, Canada. Own opinions. Go #FOAMed!