Mabel Adams

Enjoy the attached from 20+ years ago. ABOincompatible.pdf

But a perspective that is always needed, I'm sure.

The adsorption/elution showed anti-A but not at immediate spin. It reacted 2-3+ with 3 sources of A1 cells (2 different vendors' reverse cells plus an A1 donor) after 30 minutes at room temperature and was negative with 2 O reagent cells. Last wash was all negative. It doesn't matter, but what subgroup do you think it is? Am?

I guess the only risks to her of giving A red cells would be if our testing is mistaken or the next time she comes in bleeding it isn't really her but someone who is O with a missing reverse antibody that we assume is her. (Definitely chasing unicorns here.) We should be able to convince ourselves it is her as long as the new sample reacts the same as now including with anti-A,B, right? No one is likely to have time to repeat the absorption/elution. I want to leave clear instructions on her record for whatever unlucky generalist has to deal with this someday. Or would we stay with O unless/until we repeated the adsorption/elution on each specimen? BTW, can we debate why they changed "absorption" to "adsorption" 20ish years ago (ad is Latin for "to"; ab is Latin for "from")? It seems like we are usually trying so absorb antibody out of a plasma sample so "ab" makes more sense to me. Here we are trying to adsorb it onto the patient cells. I was using "absorption" because it is opposite of usual, but I had the Latin prefixes backward in my mind. I vote for a patient-sample-centric universe so "absorption" for the usual warm auto workup and "adsorption" for this sort of testing. Or less highfalutin use of language altogether and just use "absorption" because it is a more common word. I'm also interested in input from blood bankers from countries where English isn't the primary language.

We have a young (first trimester pregnant) woman who forward types as O but reverse types as A in gel and tube. No recent transfusions. The usual steps to resolve a discrepancy (cold reverse, RT inc of forward) produced no new information except we got a 1-2+ reaction with anti-A,B in tube (but nothing with anti-A reagent in tube after 30 minute room temp incubation). We have only one vendor's commercial anti-A. We are going to try absorption and elution but either way we have to decide how to transfuse her to put a note in her profile. Assuming that the eluate contains anti-A would you report her as A or as O? If you report her as A would you add a special need in the computer to give only O RBCs? If we report her as O we would add a comment to give her A plasma rather than O. Whatever we do, she is going to have an unresolvable discrepant type in the computer so none of these decisions are to keep the computer happy. I want to keep her safe from getting incompatible products but still be as accurate as possible. If we call her O they will test her baby's ABO (I know, I know) which could be wrongly typed as O (if it inherited this from mom) which makes me want to avoid testing baby, but that is not enough reason to make the decision on the mom. I appreciate any input on the case or the transfusion decisions.

This is why we treat all those weakly reacting anti-D patients as though the screen is negative and give them RhIG. It is safer even if the antibody is really a newly forming anti-D. Most of these are detected at the time of delivery so this baby is not at much risk from an immune anti-D of that low a titer. If the baby has HDFN, then we will proceed accordingly. If we pick up a weak anti-D and the patient received RhIG in the prior months but there is no record of a negative screen before the RhIG was given we will sometimes follow the patient for a few months to make sure the titer is decreasing rather than rising. We even have a test called SAB Rh Type that is for an Rh type and reflexes an antibody screen if the Rh is negative. That way we have a baseline antibody screen before RhIG is given which increases the odds that the anti-D detected later is passive.

I voted, but we actually do DAT only if the baby is positive for an antigen mom could have antibody to--Rh+ babies of Rh- moms and non O babies of O moms. I have tried for years to get them to drop the testing of babies of O moms but can't budge them.

There is a new company that I saw at the AABB meeting. Their centrifuge takes the Serofuge heads and otherwise looked promising. They will let you try it for free. Drucker Diagnostics' SERO 12 Has anyone tried it?

We don't use just the cells that Ortho marks as an abbreviated panel for ruling out other specificities in the presence of passive anti-D. We add whatever other cells are required to have double-dose expression of the usual suspects. That said, we don't require double-dose K for ruling out anti-K on antibody screens so would not require it here. Also, we don't require use of double-dose E or C positive cells in the presence of anti-D, whether passive or immune, due to the low statistical risk to the patient.

US Scenario: patient has a positive gel screen so a panel is done which doesn't key out to anything. A repeat screen in PEG or 3% cells converted to 0.8% in gel comes out negative. So we conclude that it is probably an antibody to gel diluent. We can charge for the repeat screen by a different method, but does anyone charge for the antibody ID? If so, do you feel you must report an antibody ID result? Then what? Negative? Inconclusive? Antibody to reagent? We wouldn't want anything that would interfere with future electronic crossmatch in our BBIS. Similar issues can arise with other tests sometimes.

Definitely redos use more products, especially heart valve redos. I think there are some patients on plavix that get more platelets because of that but most that get platelets get them when they are coming off the pump as those above said. We don't have TEG or ROTEM so they just judge by how much oozing they see I think. Ours don't give a ton of products but they still want a couple of red cells in the OR a fair amount.

To the elution question: if the results of the test will never alter the patient's treatment, it is hard to justify having the policy to always do the test, even if the results are academically interesting to understand causes and what is really going on.

Does anyone have experience with the Stago Hemosonics Quantra Hemostasis analyzer? I'd love to know what questions to ask if they demo it.

At the recent AABB meeting San Antonio reported on their program with whole blood out on ambulances and helicopters. When the blood bags come in with the patient to their ED, they are sent to BB so they can be crossmatched after the fact. Here, we keep segments from the units that we provide to our medical transport partner so we can crossmatch those brought to our facility if serological XM is needed or if a reaction occurs. In TX they have two level 1 trauma centers and I think more than one supplier for the units so they have to try to solve it at the receiving site.

I guess you can triangulate the data by checking several record sources but I am not sure that anything, including our own EMR, is perfect. Expired patients are still in our BBIS, we just move their ABID records to the deceased folder for another few years before discarding them. You could certainly mix up two patients who live in your area and share both full names and DOB using something like BillionGraves.