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jnadeau

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  1. Like
    jnadeau reacted to Malcolm Needs in BloodBankTalk: What is a “super Coombs” test?   
    NOBODY has EVER performed either an Indirect Coombs Test (ICT) (or, still worse, an Indirect Coombes Test), or a Direct Coombs Test (DCT) (or, still worse, a Direct Coombes Test).  There is most certainly NOT either an Indirect or Direct AHG Test.  AHG is a reagent used in both the IAT and the DAT.
    The correct terminology for the former test is the Indirect Antiglobulin Test (IAT) and for the latter test is the Direct Antiglobulin Test (DAT).  It is true that Coombs was the primary author on three papers describing the test1-3, but Mourant and Race were his co-authors on these papers, and they are often forgotten.
    Indeed, Coombs himself did not like the test being referred to as the Indirect Coombs Test and the Direct Coombs Test4, particularly as the principle of the test had been described in two papers published in the early 1900s,5, 6.
     
    1.  Coombs RRA, Mourant AE, Race RR.  Detection of weak and ‘incomplete’ Rh agglutinins: A New Test.  Lancet 1945, 246, 15-16.  DOI: 10.1016/S0140-6736(45)90806-3.
    2.  Coombs RRA, Mourant AE, Race RR.  A new test for the detection of weak and “incomplete” Rh agglutinins.  British Journal of Experimental Pathology 1945; 26(4): 255-266.
    3.  Coombs RRA, Mourant AE, Race RR.  In vivo isosensitization of red cells in babies with haemolytic disease.  Lancet 1946; 247: 264-266.  DOI: 10.1016/S0140-6736(46)91925-3.
     4.  Coombs RRA.  Historical note: past, present and future of the antiglobulin test.  Vox Sang 1998; 74: 67-73.  DOI: 10.1046/j.1423-0410.1998.7420067.x.
    5.  Moreschi C.  Neue tatsachen über die blutkörperchenagglutination.  Zbl Bakt 1908; 46: 49-51.
     6.  Friedemann U.  Weitere untersuchungen über den mechanismus der anaphylaxie.  Z Immunitätsforsch Exp Ther 1 Originale 1909; 2: 591-641 (cited in reference 4).
  2. Like
    jnadeau reacted to Neil Blumberg in Dealing With Cold Agglutinins   
    I don't think the AABB comments are evidence based.  Washing with 37 degree saline is extremely unlikely to cause false negatives with clinically significant antibodies,  and I'm unaware of any evidence that this is so.  Any such antibody would be very low affinity to be washed away by saline at any temperature, and unlikely to have in vivo/clinical significance. 
    As argued persuasively above by Malcolm Needs, anything that doesn't react at 30 degrees or above in typical serologic testing isn't going to cause clinical problems.  Patients are neither at 30 degrees nor centrifuged :).  Our serologic techniques are overly sensitive,  in general,  for clinically insignificant agglutinins. 
    No need for cold panels ever, with rare exception, and more for intellectual curiosity than clinical decision making.  Perhaps a mini-cold screen someetimes just to confirm you are indeed detecting a weak cold agglutinin in 37 degree testing, which disappears with prewarm technique. 
    Like Malcolm, I've never seen a patient with an hemolytic reaction due to an antibody that disappears with prewarming, in close to 50 years of clinical practice.  I know there are in vitro examples of clinically significant antibodies that weaken or disappear with prewarm, but I've never seen any clinical consequences.
  3. Like
    jnadeau reacted to Malcolm Needs in Dealing With Cold Agglutinins   
    We have been using pre-warming in the UK since before I started in Blood Transfusion (circa 1973) and we have never had a clinically significant transfusion reaction caused by warming away an antibody in all that time.
    Yes, there have been occasions when, for example, an anti-S has disappeared by pre-warming, but, if you look in most text books, and all reliable text books, anti-S is only rarely clinically significant - and certainly none of those that we have "warmed away" have caused any transfusion reactions at all.
    There was one case of an anti-Vel causing a fatal transfusion reaction, BUT, that was not missed through pre-warming; that was missed because EDTA plasma was used, and the anti-Vel could only be detected in serum (confirmed by the IBGRL), and so I think that the worries about pre-warming are vastly over estimated.
    It is vital to keep up with competency for this technique, as with any other technique, but probably more so with this technique.
  4. Like
    jnadeau reacted to Malcolm Needs in Dealing With Cold Agglutinins   
    Yes!
  5. Haha
    jnadeau reacted to mollyredone in Changes to Manufacturer's Inserts   
    Immucor does that.  They underline anything that has changed and use a closed triangle for anything deleted.  I've attached a copy of one from 2010.  What bugs me we get a new insert in 2016, and it was changed in 2013!  Where has it been all this time??changes.pdf
  6. Like
    jnadeau reacted to Neil Blumberg in Verbal Request for Emerg Blood   
    In emergencies, we always accept verbal orders for transfusion.  These should be followed up by a request documented in our electronic medical record, but that's after the fact.  If you have a paper system, then the followup order is documented that way.  There is a regulatory/accreditation requirement, which I consider bureaucratic, obstructive and useless,  that these emergency requests require a signed release from the ordering practitioner, if the transfusion is not fully tested for the recipient.  
  7. Like
    jnadeau got a reaction from Sherif Abd El Monem in Critical values   
    We call them "Alerts" - new hemolytic antibody identified during pregnancy, pos DAT on baby, transfusion error or serious trx, no compatible units for a specific patient or delay of product.  It's called and documented in the computer.
  8. Like
    jnadeau reacted to Neil Blumberg in Infant transfusion units   
    Just for the record, if the blood is leukoreduced, CMV testing is redundant and adds no benefit.  One less thing to complicate life. We haven't used CMV seronegative blood for any patient in 20 years and have yet to have a case of CMV associated with transfusion after >2,000 stem cell transplants and greater than 1,000 transfused premature newborns. Passive reporting, obviously, but this experience is supported by a fair amount of randomized trial and observational data. We also use recently (as in within a few days) irradiated washed red cells <21 days in storage for our newborn intensive care unit.  There is no evidence that red cells any shorter in storage provide any clinical benefit. Indeed, shorter storage red cells are associated with increased nosocomial infection in randomized trials.
  9. Like
    jnadeau reacted to Neil Blumberg in Critical values   
    We have no critical values in the Blood Bank and we have a cancer center that sees thousands of patients per month.
    And it is my recommendation that critical values be restricted to truly life threatening conditions that require treatment within minutes to hours (e.g., very high or low potassium).  I would most definitely NOT have critical values for things like creatinine/BUN, liver function tests, MCV, white count, etc.  Provides no clinically actionable information acutely, and wastes a lot of time in the lab and amongst practitioners.
  10. Like
    jnadeau reacted to Malcolm Needs in How not to miss a weak reaction   
    It sounds to me like you are doing everything that you should do, without either over-shaking the tube, or over-reading the contents.

    I am extremely glad that you are not using a microscope, as, if you did, you would almost certainly see the odd couple of red cells "kissing each other", even if they have been incubated in isotonic saline.

    The other thing is (and I speak with some 43 years of working in blood group serology) if the reactions in the tube are THAT weak, the chances of any atypical alloantibody that you might miss being clinically significant are absolutely minute.

    If you are still worried, however, get a more experienced worker to read your tests as well, until you feel confident.  That is how I learned when I started.
    I wish you the best of luck in your future career.
  11. Like
    jnadeau reacted to Bet'naSBB in How not to miss a weak reaction   
    I've been a BB'er for 35 years (at the same hospital)  my very first manager (who was a good,  seasoned BB'er) used to tell us........., "if you have to hunt for it - it's not there".
    As you become more adept at reading tube reactions - your eyes will not fail you!  Trust your gut.
    As for your technique - it all sounds good!  Practice with a few techniques to find the one that works best for you
    I "tilt and giggle", button up, The tilt helps with seeing Mixed Field - which we tend to see a lot here - It also helps with seeing "how" cells are falling off the button - are they chipping off or are they "swirling" off.....or is there a little of both?  (For some reason I always think of the "tail" of an old RPR test .....which probably dates me, LOL!)
  12. Like
    jnadeau reacted to Sherif Abd El Monem in Study With Me : Introduction to Blood Transfusion 1   
    🩸 Exciting News! 📚 Discover the fascinating world of blood transfusion by reading the book titled "Introduction to Blood Transfusion: From Donor to Recipient," published by the International Society of Blood Transfusion (ISBT). 🌍 This book will be presented in a simple question-and-answer format for easy understanding.
    https://immunohematologymadeeasy.com/study-with-me-introduction-to-blood-transfusion-1/
    Follow this in comments.
  13. Like
    jnadeau reacted to Neil Blumberg in Transfusing O positive RBCLR to O negative   
    This is why all transfusion services need experienced/trained physicians.   It's a clinical decision weighing the risks of not transfusing urgently vs. the risks of alloimmunization.  And the risks of not having Rh negative red cells for patients where such products provide important safety (girls and women <40-50; patients with anti-D). 
    Obviously the issues in alloimmunizing a male patient, particularly an older patient, are very different from a woman or girl with the potential for future pregnancy.  If not terrifically urgent, requires a discussion between the practitioner responsible for the patient and the transfusion service physician. I've certainly made decisions independently and only informed the patient's physician after the fact, when the maintenance of Rh negative red cell supply has been a priority.  Hard to write a procedure that covers all possibilities, so one would have to be broadly written, and probably kept it short on details, since these are so variable.
  14. Like
    jnadeau reacted to Neil Blumberg in CPDA-1 Blood   
    Our Red Cross just informed us that it will discontinue providing CPDA-1 rbc.  We primarily used it to provide volume reduced red cells to pediatric patients under 3 years of age.  We will volume reduce AS-1 or AS-3 by centrifugation or washing (Terumo 2991) instead.  Probably unnecessary for most patients, but this is a long standing practice here, and it doesn't seem worthwhile trying to adjust pediatric practice in this regard.  Most patients do not need the additional volume provided by the anticoagulant-preservative in AS-1, etc., and avoiding unnecessary volume is a reasonable goal in many patients. 
    There is no inherent virtue to CPDA-1 vs. AS-1 and similar solutions, and rbc preservation is slightly better in AS-1/AS-3 by in vitro metrics.  There is absolutely no factual basis for using CPD-A1 in preference to AS-1, etc. in pediatrics.  Purely expert opinion and probably unduly conservative.
     
    I've attached a nice presentation by Dr. Saifee at the University of Washington, who createdAdditive solution AS-1 in Children Univ. Washington presentation Dec 2021.pptx it to educate her colleagues about using AS-1 instead of CPDA-1.
    Additive solution AS-1 in Children Univ. Washington presentation Dec 2021.pptx
    Pediatric RBC White Paper - November 2021.pdf
  15. Like
    jnadeau reacted to Mabel Adams in Cold stored platelets and a happy BBIS   
    Has anyone considered how to build for cold stored platelets in their BBIS?  SafeTraceTx at least, has expected temperature ranges for products on return from issue or delivery so we couldn't very well lump cold stored platelets in with other platelets.  I guess we could build an entirely new product class with its own temperature range.  Not that we are going to get cold-stored platelets anytime soon, much as we would love the 14-day shelf life.  We are too small and remote to keep a dual inventory for oncology vs. trauma patients.  I'm just curious how others plan to solve this issue.  After all, the driving force of our lives is keeping our computers happy, right?  Now if FDA would just approve 7-day expiration for all PR platelets!
  16. Like
    jnadeau reacted to Mabel Adams in Post-partum workup   
    There used to be a regulation that the birth parent not be sensitized to D to be a RhIG candidate.  We trust that the baby lacking a positive DAT due to anti-D is sufficient evidence and have not done anything but the needed Fetal Screen in a couple of decades, even when we didn't do admission T&S routinely.  I think key is what will we do differently with the results?  If you detect anti-D, you will assume it is RhIG and give RhIG again.  If the Ab screen is negative, you will give RhIG.  The test doesn't change the treatment so why do it?  This assumes that a strong anti-D, clearly due to sensitization, would cause the baby to have a positive DAT and therefore any needed workup would be completed for that reason.
  17. Sad
    jnadeau reacted to AMcCord in Post-partum workup   
    Nothing is ever simple, is it? Especially when you get other folks involved.
    I stopped a dose of RhoGAM from being given to the baby. I've had nurses squirt some out of the syringe because "it's an early miscarriage, they don't need the full dose". I asked how they were calculating that dose and how did they know how much they squirted out...no answer . 
  18. Thanks
    jnadeau reacted to Sherif Abd El Monem in Clear as Glass Blood Banking - Sue Johnson.   
    Clear as Glass Blood Banking - Sue Johnson.
    Topics Include:
    -Evaluating Antibody Identification Panel Results
    -Resolution of ABO Discrepancies
    -Serologic Weak D Phenotype evaluation
    -Direct Antiglobulin Test(DAT)
    https://immunohematologymadeeasy.com/clear-as-glass-blood-banking-sue-johnson/
  19. Like
    jnadeau reacted to Mabel Adams in Prenatal Antibody Titers   
    I always based my judgement on the fact that the original studies to determine significant titers were done using double dose cells.  Plus, nowadays, with donor eggs, the baby can be homozygous for the antigen.
  20. Like
    jnadeau reacted to Ensis01 in Incompatible Blood   
    Agreed. I would however like to add the caveat that some physicians do not understand the risks associated with antibody history and uncrossmatched blood, so getting a pathologist involved to ensure the situation is truly life/death. 
  21. Like
    jnadeau reacted to Ensis01 in Antibody Testing Report Terminology   
    For an antibody screen “Neg” or “Negative” has been historically used. This may have been heavily influenced by DOS based computer systems that had very limited memory so “Neg” made sense.
    Reporting a SCREEN as negative seems logical to me, however a work-up requires more detail as Malcom’s described above. 
  22. Like
    jnadeau reacted to Malcolm Needs in Antibody Testing Report Terminology   
    I meant that they would NOT report it as "Negative", or "No Antibodies", but WOULD report occasionally as "All Clinically-significant Allo-antibodies have been Ruled Out using etc.", or words to that effect.
  23. Thanks
    jnadeau got a reaction from Malcolm Needs in Antibody Testing Report Terminology   
    Thank you very much Malcolm - you're the best!  If you would clarify in the second paragraph please - worth their salt "would" or "would not" report out...  we're filled with Canadian smoke here and it may be causing me confusion
     
  24. Like
    jnadeau reacted to NicolePCanada in Antibody Testing Report Terminology   
    Stop blaming the Canadian Smoke. We in Canada, do result as No Antibodies detected. If the patient had an antibody in the past, that is maybe below detectable limits, but was previously identified, those are also in report as historical and as such the patient would have a full crossmatch in gel as well as phenotypically matched for previously discovered antibodies.
  25. Like
    jnadeau reacted to tbostock in Pt reacting to mts diluent   
    We have seen this too quite a few times. We jokingly call them "gelibodies".
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