Each blood bank has what they would consider clinically significant, somewhat significant and not so significant antibodies. At our blood bank we consider anti-D, -C, -E, -c, -e, -S, -s, -K, -Fya, -Fyb, -Jka, -Jkb (most common antibodies ); -Cw, -V, -Kpa, -Jsa, -Lua (uncommon antibodies); -Kpb, -Jsb, -Lub, -k (rarely seen antibodies); -f(ce) (uncommon). Any of these antibodies would cause a (most likely severe) transfusion reaction. Antibodies like cold autos, cold agglutinins, warm autos and warm panagglutinins have variable significance and would cause antibody screen and panel cells to be positive across the board, including crossmatches. Antibodies like anti-M, -N, -Lea, -Leb, -P1, and A1 we consider not significant due to they are cold reacting antibodies, which do not bind at 37C or react at AHG phase. For these antibodies, we can do a prewarm crossmatch and if compatible, we will instruct that cells are warmed up prior to transfusion and continue to stay warm throughout the transfusion (same as cold autos and agglutinins).
I'd be curious to know what your blood bank's testing methodology is (instrument - solid phase or gel, manual gel card, classic tube method, etc.). For automation, we use an Immucor Galileo Echo (updating to automated gel card) and we have issues with some patients where their antibody screen and subsequent panel cells are all positive (sometimes there are only a few that are positive). We then do an antibody screen in tube including 37C phase and the screen is now negative. We result the antibody screen as negative and call it an NSA (non-specific agglutination); this is a very common occurrence with the Immucor Galileo Echo. I only described this because antibody screens can be positive for a few reasons besides the patient having an antibody and delaying transfusion.
To others saying to transfuse O Negative cells: If we have history, giving A positive blood would be the way to go.
Unless she's got something like an anti-C or -E (or the techs are thinking it's a -C or -E), giving Rh negative blood would significantly help since those antigens are less likely to be present on Rh negative donor cells (when I test for those antigens,
usually 3 out of 4 units are negative for those antigens). Anti-c and -e are even more challenging (especially anti-e) as these antigens are most likely to be present on the donor cells (for anti-e: 98% frequency, which is more than the -D/Rh antigen! and there are others that have a higher frequency like -k w/ it's 99.8% frequency!).
The reason I brought up transfusing Rh negative cells is that it would only help if the patient is suspected of having either one of those antibodies. If she has any other antibody besides -C or -E it would be pointless to transfuse Rh negative blood unless we do not have a previous blood type on file.
The cross was positive. I wouldn’t use the blood that was already crossed. I would ask for a type-specific uncrossed unit as that would have a lower risk of incompatibility as compared to the already crossed blood that was shown to be positive.
The best thing for a blood banker to do is crossmatch and issue units with least incompatibility. I understand the premise of your response but this is something a good blood banker would tell you NOT to do. Without testing for compatibility, you are taking an ABSOLUTELY HUGE BET that she's receiving units with worse incompatibility than others. Of course you are the judge with her clinical presentation but if we can give you units to have on hand and then call you when we have other units available with less incompatibility, I would prefer you to do this.
The first thing I would do (as a tech) is notify our pathologists. At the same time, I'd be looking at her history to see if we can find any results from a previous type and screen w/antibody identification (probably come up empty because of next sentence). I'd probably call you guys next to see who her OBGYN is and ask if they have any history (never mind I see above she hasn't received routine care...s hit). Hopefully your blood bank works efficiently and maybe has a panel on to start ruling out/in whatever it can be. I'd be concerned about the baby as they may have been impacted by mom's possible antibody and could possibly have HDN upon arrival into the new world.
Most blood banks would have some sort of form that basically holds you accountable
(not to get in you trouble but to cover out butts in that we didn't just issue w/out notifying you that there may be a issue during and possibly after transfusion, ie a paper trail) if the patient has any adverse reaction with transfusing blood. It'll basically state you are responsible and fully acknowledge that the blood is incompatible for her. Obviously you'd have to sign it and bring it back to us. We issue them for patients with cold agglutinins, warm auto/pans, etc. because their crossmatches are always incompatible and the attending physician has to sign them because due to their incompatibility. In this instance, we'd end up indicating the emergent need for blood with a positive antibody screen and no phenotypically compatible cells available with a resulting incompatibility.
God I hope this was a hypothetical scenario because I would be s hitting bricks in that blood bank. I hate to admit it but I get a huge adrenaline rush with these types of scenarios. I love to play cowboy in the blood bank when stuff like this happens since many of my coworkers hate these situations and often don't know where to start.
Sorry I'm editing my poor grammar. I thought it all sounded good when I posted. My apologies for the notification
😀
It's probably a blessing to be living in Cleveland with Case's Anesthesiologist Assistant 20 minutes away from home 
