To aliquote off plasma from banded specimen or not...

[lalamb]

Our current policy is to aliquote off the plasma from a banded specimen into a pour- off tube,( that is properly labeled, per our policy).

As we have recently switched from serum to 10ml EDTA plasma tubes, is aliquoting still necessary?

Found no reference/requirement for this in AABB, I called AABB and they said there is no regulation for this and that~ 1/2 of hospital do aliquote off and 1/2 don't.

The rgt manufacturer (Immucor) insert talks about "run as soon as possible, ..several days...prolonged periods". Those time intervals are not defined. They suggested, if I don't want to pour off the plasma, I do validation studies to see how long rxn's are still good over a period of time. Don't really want to go there...

Any thoughts / concrete evidnce / reasons for choosing one way or the other?

We do tube method w/PEG. thanks lal

[adiescast]

We don't pour off the plasma, but it is as much a philosophical decision as anything since there is no concrete evidence that I know of. My concern with doing pour offs if you do not have to is that it creates room for errors in labeling or mixing up aliquot tubes.

One potential problem with not pouring off is that an allo antibody could be adsorbed out of the plasma onto any donor cells present in the tube. This is only going to be a problem if you wait a significant period of time before performing a screen (see, there is that uncertainty principle again - what is a significant period of time?) and do not routinely perform auto controls with your screens (which we do not).

I don't know that these thoughts will help with your dilemma. Perhaps others will chime in with something more concrete...