IO stands for "intraosseous"-into the bone. It is, in effect, a electric power drill, made use of to bore a gap by bone and into the marrow, and therefore does not call for locating a vein. He ultimately observed a minor flashback, then shed the vein and couldn’t get the needle back in. As Zellmer tried using to get the needle into the jugular, the paramedic trapped Lockett three extra situations on his appropriate arm, failing every time.