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.
