Malcolm Needs

We have the compatibility question on the pre-transfusion checklist in Meditech TAR.  We were also cited for this several years ago and have not had a problem with this since.  Whether the RN understands is another question though.

I tried hard a few years ago to find evidence for this but found nearly nothing in terms of evidence-based guidelines.  I will try to add here what I came up with, but it is fairly arbitrary.  It is part of our MTP document.  It loses a lot of formatting here.  Sorry.  Broselow Tape is used in ED to estimate the size of a child.  Maybe see if your ED can share what this looks like.  This information is intended to be of practical use as a loose guideline for the poor blood banker working on the unusual day that we get a pediatric hemorrhage in.  I am very open to improvements.   Good luck!
Broselow Tape Patient Size Correlation:
 
Grey
3-5 kg
Pink
6-7 kg
Red
8-9 kg
Purple
10-11 kg
Yellow
12-14 kg
White
15-18 kg
Blue
19-23 kg
Orange
24-29 kg
Green
30-36 kg
Wt. in Lbs.
 
7-11
 
13-15
 
18-20
 
22-24
 
26-31
 
33-40
 
42-51
 
53-64
 
66-79
Approx age
 
< 3 mo.
 
3-9 mo.
 
4-15 mo.
 
1-2 yr.
 
2-3 yr.
 
4-5 yr.
 
6-7 yr.
 
8-9 yr.
 
10-11 yr.
 1 unit Platelet order at SCHS = 1 apheresis platelet = 6 units of whole-blood-derived platelet (6 pack)
Product = any and all types of blood component therapy, to include RBC, plasma, platelets, and cryoprecipitate. Bend only: Group A plasma may be used as universal donor plasma for adults and children over about age 5. Blood Products
Grey
3-5 kg
Pink
6-7 kg
Red
8-9 kg
Purple
10-11 kg
Yellow
12-14 kg
White
15-18 kg
Blue
19-23 kg
Orange
24-29 kg
Green
30-36 kg
Adult
 
MTP Round 1
10 ml/kg is ~equivalent to 1 unit RBCs to an adult.
                            
Red Cells
1 unit *
 
1 unit *
 
1 unit 
1 units
1 units
2 units
3 units
3 units
4 units
4 units
Plasma
1 unit †
 
1 unit †
 
1 unit †
 
1 unit †
 
1 unit †
 
2 units †
2 units
2 units
2 units
2 units
Platelets
‡
‡
‡
‡
‡
 
 
 
 
 
Cryoprecipitate
1 single cryo as ordered or if Fib <100
1 single cryo as ordered or if Fib <100
1 single cryo as ordered or if Fib <100
1 single cryo as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
MTP Round 2
Repeat Round 1
Repeat Round 1
Repeat Round 1
Repeat Round 1
Repeat Round 1
 
 
 
 
 
Red Cells
1 unit *
 
1 unit *
 
1 unit *
 
1 units
1 units
2 units
3 units
3 units
4 units
4 units
Plasma
1 unit †
 
1 unit †
 
1 unit †
 
1 unit †
 
1 unit †
 
2 units †
3 units
3 units
4 units
4 units
Platelets
‡
‡
‡
‡
‡
1
1
1
1
1
Cryoprecipitate
1 single cryo as ordered or if Fib <100
1 single cryo as ordered or if Fib <100
1 single cryo as ordered or if Fib <100
1 single cryo as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
MTP Round 3
Repeat Round 1
Repeat Round 1
Repeat Round 1
Repeat Round 1
Repeat Round 1
 
 
 
 
 
Red Cells
 
 
 
 
 
2 units
3 units
3 units
4 units
4 units
Plasma
 
 
 
 
 
2 units †
3 units
3 units
4 units
4 units
Platelets
 
 
 
 
 
 
 
 
 
 
Cryoprecipitate
 
 
 
 
 
1 pool of 5 as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
1 pool of 5 as ordered or if Fib <100
Continuing Rounds
 
 
 
 
 
Repeat Rounds
2 & 3
Repeat Rounds
2 & 3
Repeat Rounds
2 & 3
Repeat Rounds
2 & 3
Repeat Rounds
2 & 3
* If < 4 months old (grey & pink)
·         Irradiated blood & platelets not required unless specifically ordered by physician.
·         Continue to give only O RBCs & AB plasma regardless of baby’s blood type.
·         Unless AB platelets are available or they request otherwise, wait to give ABO-incompatible platelets until the baby has had a partial transfusion of O RBCs to reduce ABO incompatibility.  Avoid giving O platelets on a non-O baby.
·         Syringes with filters issued with RBCs and platelets in case preferred over blood administration set.
·         Still must use blood warmer for massive transfusion if syringes used.
·         All blood products must be filtered, either by blood administration set or syringe with filter.
† Thaw AB plasma as universal donor on all peds under ~18 kg (40 lbs.—around age 5). Don’t use A plasma for them as universal donor without physician/pathologist approval.
‡ Issue platelets with instructions to give only part of the unit or run it as needed over 4 hours (or can aliquot if time).  These are the fractions of a unit proportional to the RBCs being given in each round. Communicate this information to nurse.
Grey
3-5 kg
Pink
6-7 kg
Red
8-9 kg
Purple
10-11 kg
Yellow
12-14 kg
1/5
1/5
1/3
1/3
1
This policy does not apply to exchange transfusions of neonates.
 
 

First let me say I am honored that Malcolm Needs responded to my question. I have enjoyed reading (I guess I'm a lurker) this forum for years. Pre PathLab days.
 Our longtime Ortho Rep was assigned a new territory, since then we have had sporadic contact. This coincided with a very good Bio-Rad Rep.  I'm impressed with Bio-Rad. I am looking at IH Centrifuge, Incubator and Reader. 
  Thank you for the information. I meet with our Bio-Rad Rep March 22 to review the proposal. 

I am enormously honoured to announce that I am going to be awarded the Gold Medal of the British Blood Transfusion Society at their Annual Scientific Meeting in Brighton this year.  It is awarded to an individual for their exceptional and long standing services to the Society and to the practice of blood transfusion in the UK.  Sorry if this sounds egocentric, but I am very excited.

UNOS has guidelines on off-type kidney transplants.  We were using the UNOS protocol for DTT treated iso-titers, but have transitioned to running IgG and IgM iso-titers on our NEO Iris.
https://community.asn-online.org/blogs/mark-lerman/2018/07/09/weekly-rewind-abo-incompatible-kidney-transplant-r
https://optn.transplant.hrsa.gov/media/2347/mac_guidance_201712.pdf
 

Somewhere, in Patrick Mollison's work, cited in Blood Transfusion in Clinical Medicine, he mentions that IgG ABO antibodies are more clinically significant in solid organ transplants than are IgM (if I remember correctly, he specifically mentioned renal transplants), but I cannot cite the exact paper off the top of my head (I will see if I can find the reference).

As a result, whenever we were dealing with a renal transplant that crosses the ABO barrier, we almost performed an IgM and an a separate IgG titre.  Whether this is now considered to be necessary, I will leave to other people to discuss!

I am enormously honoured to announce that I am going to be awarded the Gold Medal of the British Blood Transfusion Society at their Annual Scientific Meeting in Brighton this year.  It is awarded to an individual for their exceptional and long standing services to the Society and to the practice of blood transfusion in the UK.  Sorry if this sounds egocentric, but I am very excited.

Beers on me Bro !!

I missed this. It was during my granddaughter's illness. Congratulations Malcolm!

Congratulations, Malcolm! Very well deserved!

I am enormously honoured to announce that I am going to be awarded the Gold Medal of the British Blood Transfusion Society at their Annual Scientific Meeting in Brighton this year.  It is awarded to an individual for their exceptional and long standing services to the Society and to the practice of blood transfusion in the UK.  Sorry if this sounds egocentric, but I am very excited.

Well, that's got rid of two of my possible theories in one fell swoop!

I was wondering either about loss of antigenicity due to some form of myeloid malignancy, or of adsorption of autologous secreted A substance on to the  donor group O red cell surface following a successful BMT or stem cell transplant, which may be seen with only some clones of anti-A (see, for example, Cripps K, Mullanfiroze K, Hill A, Moss R, Kricke S.  Prevalence of adsorbed A antigen onto donor-derived group O red cells in children following stem cell transplantation: A single-centre evaluation.  Vox Sang 2023; 118: 153-159.  DOI.10.1111/vox.13386., but I saw this phenomenon in adults many times when working at Westminster Hospital).

Oh well, back to having more thoughts!

I can fully understand what you are saying (and agree almost 100%), but I do have some sympathy for them signing the forms "after the event" as it were, because when they do have to use the uncrossmatched blood that quickly, then they are going to be pretty busy doing things like preventing the demise of the patient - if you see what I mean!!!!!!!!!

Malcolm, I meant that statement not as a criticism of them but just a recognition of reality.  Frankly I was excited to get the forms back most of the time and fully understood the pressure they were under.  When I was in school I worked in the emergency room on night shift so I was very familiar with trauma situations and fully understood the, "do it now and worry about the paperwork later" mentality. 
Cheers  

Also, fetal bleed screen testing on a spun sample.  Those giant fetal cells will be on top.  Mix well before testing!

Bg antibodies are antibodies directed against HLA Class I antigens.
These antigens are expressed quite strongly on virtually all nucleated cells, but are poorly expressed on red cells.  This is purely down to the number of antigens sites on the various cells.  For example, a T lymphocyte will express some 100, 000 such antigens on their surface, whereas a red cell will only express from 40 to 500 such antigens.
It was originally thought that Bg antigens on red cells were adsorbed onto the red cell surface from the plasma, but it now seems that these antigens may be intrinsic, having been formed during the time when the erythrocyte precursors actually had a nucleus, but, that notwithstanding, they can easy be removed from the red cell by chloroquine treatment.
Bga is analogous with HLA-B7, Bgb is analogous with HLA-B17 and Bgc with HLA-A28, but there may be cross-reactivity with other HLA antigens.
Bg antibodies are very common in pregnancy, having been stimulated by the foetal HLA antigens, but have never been implicated in clinically significant HDFN, so neither you, nor the expectant mother need to worry (they are "nuisance" antibodies).
For more information, try Geoff Daniels, Human Blood Groups, third edition, 2013, Blackwell Publishing Ltd. Chapter 32 (pages 512 - 514) - so there is not a lot to read!

Well, that's got rid of two of my possible theories in one fell swoop!

I was wondering either about loss of antigenicity due to some form of myeloid malignancy, or of adsorption of autologous secreted A substance on to the  donor group O red cell surface following a successful BMT or stem cell transplant, which may be seen with only some clones of anti-A (see, for example, Cripps K, Mullanfiroze K, Hill A, Moss R, Kricke S.  Prevalence of adsorbed A antigen onto donor-derived group O red cells in children following stem cell transplantation: A single-centre evaluation.  Vox Sang 2023; 118: 153-159.  DOI.10.1111/vox.13386., but I saw this phenomenon in adults many times when working at Westminster Hospital).

Oh well, back to having more thoughts!

The same phenomenon is seen if you use a spun sample for DATs.
The cells at the top can be negative and the ones from the bottom positive if recently transfused.

Thank you all so much for your explanations. I agree with jayinsat regarding the importance of transfusion history in this case, but I would have expected mixed field on the instrument, which was not the case. The concept of the density difference between the autologous RBCs vs the transfused RBCs and its impact on the probe sampling is very fascinating. Thank you all for sharing the papers that explain this phenomenon.

Well, that's got rid of two of my possible theories in one fell swoop!

I was wondering either about loss of antigenicity due to some form of myeloid malignancy, or of adsorption of autologous secreted A substance on to the  donor group O red cell surface following a successful BMT or stem cell transplant, which may be seen with only some clones of anti-A (see, for example, Cripps K, Mullanfiroze K, Hill A, Moss R, Kricke S.  Prevalence of adsorbed A antigen onto donor-derived group O red cells in children following stem cell transplantation: A single-centre evaluation.  Vox Sang 2023; 118: 153-159.  DOI.10.1111/vox.13386., but I saw this phenomenon in adults many times when working at Westminster Hospital).

Oh well, back to having more thoughts!

Thanks for this explanation Arno.  I should have thought of it myself (but didn't!) as my friend Bill Chaffe, a former President of the BBTS described just such a situation in a meeting a few years back.

The most likely answer has been given above: newly formed autologous red cells have a lower gravity than transfused cells and will concentrate at the top of the re cell pellet whereas transfused cells will seat at the bottom. I hereby attach a paper describing that phenomenon. I hope Grifols will thank you for giving them the answer :-)     20230301142735376.pdf20230301142735376.pdf

The patient was admitted into our ER for severe anemia likely due to GI bleed. His HgB was 3.7 g/dL when admitted. Received 3 emergency Opos RBCs units. The type and screen on Erytra was performed after the transfusion of the first 3 units.

Would you be able to disclose the underlying pathology of the patient please?

I agree with both Bet'naSBB and jayinsat in that it is probably an antibody directed against a low prevalence antigen.  The problem with identifying the specificity of such an antibody is that there are so many!  To make certain that it is not a "fool's errand", it might be worthwhile trying to get a sample of blood from the putative father, if he is available and/or known.  As the baby is, like the mother, group O, there is a 50% chance that the father will also be group O, in which case it is simple to see if his red cells can be sensitised by a maternal antibody.  If he is not group O, everything is not lost as, as jayinsat suggests, an eluate from the baby's red cells should be clear of all anti-A and/or anti-B.
If the putative father's red cells are compatible by all methods, either there is another explanation for the positive DAT, or he is not the father (or both).

The other thing that springs to mind is that, even if there is an antibody directed against a low prevalence antigen, as you have not identified a specificity using your standard panel, and should the baby develop a clinically significant case of HDN (it is too late for HDF) and require a transfusion, acquiring crossmatch compatible blood, suitable for the baby, should be a simple task.