according to CSI the Order in which Tubes should be filled is the same whether using a tube Holder or syringe first sterile Blood Culture Tubes or vials second Blue Stopper sodium citrate Tubes third Serum tube with or without clot Activator or gel separator fourth hein or Green Stopper Tubes Fifth lavender Stopper edta Tubes sixth Gray toop or glyco inhibitor Tubes although this Order is recommended some facilities have modified this Order based on internal studies and variables Unique to their System therefore follow your facility established protocol it's been widely document that the needle piercing a tube Stopper can transfer One tube additive into The next even a minute amount can drastic alter test results on the subsequent tube If randomly filled following the presed Order of Draw doesn't prevent additive carryover but makes it irrelevant Because of the Nature of testing generally performed on each Two Of course we All know the reason we have to follow the recommended Order of Draw is because additives can Carry over from One tube to The next and significant alter the test results of the subsequent tube this happens When The needle pier The Stopper Uh it comes in contact with the blooded additive Mixture of the filled tube and When the needle is removed and another Stopper is pierced in The next tube that additive Mixture can Carry Over and contaminate the contents Uh Of The next tube for example if We're drawing an edta tube out of the Order and Uh because edta is High in potassium by Nature we could be inadvertent sping the test result if that second tube is to be tested for potassium and if that patient happens to be low In potassium and we Draw that edta tube in the wrong Order it can add enough edta to the subsequent tube that is tested for potassium to make the test result reflect that the patient has a normal level of potassium now this Can Be pretty disastrous for patient Who's being cleared for surgery Who shouldn't really go to because potassium is too Low