mrstymt

i'm not sure if this fits - but since it's a thread on Antibody ID, i figured i'd ask. i read in the AABB technical manual that Fisher's Rule of Three doesn't necessarily apply to all approaches in ensuring an identification with minimal statistical error (P<0.05), and that sometimes other methods are applicable (i.e. 2 negatives, 3 positives or 1 postive and 7 negatives and such...) we had a case where a cord blood was DAT positive, but since we had barely any cord red cells, we recovered a very small amount of eluate that, if pipetted as per manufacturer's recommendations, we would only have enough eluate to last 9 cells in one panel by gel. the mom's screen was anti-D, possible due to RhIg. if the panel's pattern matches anti-D up to cell 9 (which it did) - would the alternate approaches (non-Fisher's) be enough to confirm that the eluate demonstrated anti-D? the reason why i'm asking is because, even though i suggested this information on alternate "rules", our BB techs have been hesitant in just ruling out anti-K with 1 heterozygous cell, regardless of its phenotypic frequency. instead, they have to find 2 additional selected cells at most to make sure it reacts negatively with the patient's serum or eluate. also, we usually would need 2 additional selected cells treated with ficin to rule out anti-C and anti-E by gel because there are no homozygous expression for those antigens with the D antigen being negative. i was always taught that you use a combination of rule-outs with homozygous cells and the statistical "Rule of Three" if a pattern in reactivity matches that of an antibody in the cell lines. but it seems like at my institution, we're doing endless repeat selected cells trying to rule out anti-K, C, and E just because of the "Rule of Three", even if the reactivity pattern fits and at least one or two of the alternate "rules" apply. thanks!

wow, i'm so glad i stumbled upon this thread, because i seriously don't know what goes on in the OR as well. so i would assume that any patient ID band (admission band, BB band, etc) gets cut off before entering the OR for "sterile" purposes. so if you don't work with BB bands, does that also present a problem with just name and MR#? and yes, shame on us younger BB techs who can't come up with microchips and tattoos as patient identifiers. but then again, we don't have the money to do that right now maybe soon, if this whole electronic MRs happen. i will be sure to present this to my BB administration i don't think they do enough observations throughout the hospital (nor they can due to shortage of staff)

darn i wished i saw this thread before answering this question wrong the other day. at least i knew that i had to send it to reference

I'm not very good at recognizing HTLAs right of the bat (and esp. because i work at a hospital and not a reference lab), but I would think that "high titer" means a larger number than 2... and definitely not use gel with HTLA because it'll just react panagglutinable.

It's either our policies are asking for WAY too much, or at least I'd feel more comfortable with the "extended" TRW... We do clerical, pre- and post- DAT, visual check pre and post, Type and screen pre- and post- (argh, that's a lot already!!), bag culture, first void urinalysis. And these are all on products, RBCs and platelets more common than others. If it is febrile, we do 1 set blood cultures. There is an outline for each step (like step 1, yes, continue, step 1 no? stop..) But basically we request all the samples at call of TRW and then we follow the outline. However, when we call the pathologists, they expect the Type and screen to have been repeated on pre and post regardless if the top 3 were negative for errors. Now ask me if I agree with this.....someone in this thread already said that the PPV doesn't really make much of a difference from all this work. If our automated system is up, no problem, just load pre and post and done. If we're manual (like we are now since we've been having automation problems), it's quite a kicker. It takes you away from the other work you have to do. Good luck!

In reference to drsbright's reply, my blood bank just recently adopted going back to tube testing until all these Gel problems have been resolved. I have been telling my colleagues that I'd much rather work up false-positives than false-negatives. I feel that, although the reference lab we contract with uses tube method as their primary technique, our going back to tube method doesn't exactly mean diddly because reference lab uses different types of reagents than we do. Another reason why I say that is because -- from what I've been reading in this thread, PEG seems to be more reproducible with Gel technology than LISS/Enhancement solutions. If I understand this correctly, a 2+ gel reaction would be missed if we use LISS/Enhancement, which we do. And this would then explain why repeating all positive gel screens by tube method doesn't really make any sense. So, until Ortho sends a representative to help us understand why we have these weird reactions, our blood bank will be doing tube type, and eventually, we will run out of tech power and 3% screening cells/panels in a week. I mean, they won't even suggest looking into techniques or something. I haven't been working long, but there's gotta be a better way than just dropping your primary system and switching back to tube because "reference lab does it" Thanks for all your ideas!

I've done this on numerous occassions, also a colleague did this recently. We took a Panocell 3% and converted it to 0.8% and run them in gel. I personally would dilute them with the MTS regular diluent (not MTS Plus). I had one patient where I ruled out Anti-S with the Panocell diluted to 0.8%, but I eventually decided to send it out to reference lab. Results came back positive for Anti-S. My colleague said she couldn't rule out Anti-K with Panocell diluted to 0.8% -- it was reacting negative to those cell lines but the panel clearly shows multiple antibodies (1+ to 2+ reactions), and Anti-E was clearly present. So as much as I thought theoretically it would work, diluting the Panocell from 3% to 0.8% may have decreased the number of antigen sites available on these cells. Maybe they weren't made to be diluted for Gel card use, I don't remember seeing that on the reagent insert though. As for respinning the Gel cards -- I'm personally not comfortable with that practice. I've had cards where it didn't spin right (agglutination toward one side of the column), and I've had gel cards where it looks like it was dried up, very minimal liquid in the column present, and one Ortho rep had told us to pre-spin it before use. Maybe our administration should just consider expanding the blood bank so that the cards are adequately stored in the right temperatures (although they claimed an Ortho rep did come in and said it was ok....I don't know about that), and maybe my BB supervisor should just get the MTS centrifuge fixed because respinning cards I think is just a bad way to practice Gel methodology. But hey, my administration is another story

I'm relatively new in the field, but I was wondering what the actual AABB Tech manual and Standards say about the "flagging" Rh pos, DAT pos Cord Blood work-up to received Rh neg blood. Our current policy for newborns have always been to transfuse O neg packed cells for all newborns.

I am currently new to the world of BloodBankTalk, and moreover, new to the world of Blood Bank practice! I have been working as a generalist at my hospital for about 10 months now, recently graduated from an MT program in 2007. I guess you would say this is the time where I find and develop my "niche", and so far, it's Blood Bank! I am interested in eventually specializing in BB, and am looking forward to all the things I can learn from here in this forum. Thanks!