its a waste of time,ever see any Dr's Aspirate? of course not, I work at a hostipal there they will stick you and if it goes into a vein(oops) when they pull out they cover their mistake with a cotton swab followed by a band aid,Thanks Nurse ! in 25 yrs i have never had a problem, but i researched close to a yr on here , so i was well versed on things when i started .