Hello, I'm writing know an assignment about Central venous line, blood withdrawal between discarding the wast specimen " the first 5 cc" or flush it back to the vein In ICU i want the reasons, why we must not flush it back with a reference or a hospital policy because i saw many answers told "discard it" with many reasons. But i want it with an evidence, there are no articles that give even a reasons. that's why i'm struggling xD and thank u all