When placing a central line, a question that occasionally arises is whether you are in the artery or vein? Here's a video compliments of Dr. Weingart of the EMCrit Blog on a novel technique to help figure it out before you dilate the vessel.

Are you in the Artery or the Vein? from Scott from EMCrit on Vimeo.

Source

http://emcrit.org/central-lines/