UMEM Educational Pearls

Category: Ultrasound

Title: US Guided LP Site Marking

Keywords: POCUS; Lumbar Puncture; Neurology (PubMed Search)

Posted: 4/15/2024 by Alexis Salerno, MD (Updated: 5/1/2024)
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Simple tool to help improve your next lumbar puncture: Use ultrasound for site marking.

This can be done in a patient sitting up or laying on their side.

-First start with the probe marker midline towards the patient's head and use the ultrasound to identify the L4/L5 and L3/L4 space.

-Use a surgical pen away from the gel to mark midline on both sides of the probe, using the midline marker on the ultrasound probe. You can use m mode to help you identify the middle of the image when using a curvilinear probe. 

-Then rotate the probe towards the patient's left and use the ultrasound to identify the midline point (spinous process)

-Use a surgical pen away from the gel to mark midline on both sides of the probe, using the midline marker on the ultrasound probe.

-Clean off the gel, connect the skin markings and use a 3 cc syringe to mark the center of the crosshair. 

-Sterilize and start your LP!