no one can really tell where the tip is unless the xray film is in front of you...the best thing to do is document and call the picc line nurse (if you have one) if not call md to order stat chest xray to confirm placement... that is the best thing to do....
it is a risk /benefit issue.... i did a picc line on a pt with inr of 3.4 and it was ok.... ill do it if the patient is in ICU and i know somebody will always be watching the pt if he/she is bleeding... if pt is in medsurg and nobody will monitor the site I wont do it.