when infiltration happens during any type of needle insertion,such as a blood draw or even when starting an IV,it simply means 'thru and thru'. they actually are holding the needle usually at too much of a higher angle so when they go to "stick' it goes completely thru the vein(both walls of) and not "into it" as it is supposed to. does that make sense? you can usually tell somone who has had an infiltration by just looking at the draw site,blood will be under the skin in the form of a bruise? some will only bleed a bit but others can bleed alot,espescially if they are on aspirin or blood thinners.
as long as they actually "hit" the inside of that vein,even if they actually somehow get in thru more of the side,it still would be okay only as long as that needle gets into that vein. you can tell as soon as the person doing the test pulls back on that plunger part of the syringe? just look for that 'flash" of blood as soon as they pull back and create that suction(the "draw"). if you don't see blood,then they either missed the vein completely or infiltrated right thru it and out the other side of that vein.
if i may ask,just why do you need that many blood draws per month? about the only thing you can do to try and prevent scar tissue,tho with that many draws it would be kind of hard to avoid it,is change the vein spots that are being used around a bit so you are not hitting that same vein over and over again so quickly,you know what i mean? giving the veins kind of a "rest' in between the seperate draws really would be about the only thing i can think of to help your situation.
there is another form of set up called the butterfly that uses the vein a bit further down from the one in the inside elbow area? this is my and my sons particular favorite(it doesn't hurt as much,espescially when they have to change out the tubes?),it also is much harder to actually infiltrate with this set up since it has to be help totally parallel to the vein in order to just slide it into the vein at all. just a really good suggestion. hope this helped niad,Marcia