In-vivo Crossmatch

[Liz]

When you issue a unit that is compatible with the adsorbed serum but not with the neat serum, do you request that an in-vivo crossmatch be performed?

In General, is the in-vivo still being requested and is so, when?

Thanks,

Liz :cool:

[rravkin@aol.com]

Liz,

Could you explain what an "in-vivo crossmatch" is? I am not familiar with this term. Under the circumstances described we would perform an Extended, or IgG, crossmatch using neat serum or plasma.

[Malcolm Needs ☆]

I must admit that I am not familiar with this term either.

It rather reads like one transfuses the blood to the patient and you then see if they survive or not (which I am certain is not what you mean)!!!!!!!!!!!!!!!!!!

:eek::eek:

[adiescast]

I assume you are talking about giving the patient a small amount of the unit and watching for reactions? We do not use it.

[Fluffy agglutinates]

I always thought this was the transfusion equivalent of an urban myth - give a small amount to the patient, wait a few minutes, take a fresh sample, spin & look for haemolysis in the plasma!

If anything, this would only pick up ABO incompatibility & I would not want my immune response tested in this way!!!

Seriously does anyone actually do this? I think it would lead to a false sense of security.

Also heard it called a 'biological crossmatch'

[L106]

Fluffy agglutinates has it right. Her first sentence describes exactly what an "in vivo" crossmatch is. It would pick up major ABO incompatibilities and possibly other antibodies capable of causing immediate hemolysis (typically, some IgM antibodies.) This was a procedure utilized as a "last-ditch-effort" 30-40 years ago when the patient had a horrendous variety of antibodies, or you couldn't figure out what the antibodies were, or perhaps something like leukoagglutinins, and you could not find "compatible" donor units.

I haven't heard of anyone using the procedure for many years.

Donna

[David Saikin]

Ulp - My pathologist likes this whenever we do "incompatible" transfusions. Makes him feel better.

[Malcolm Needs ☆]

I always thought this was the transfusion equivalent of an urban myth - give a small amount to the patient, wait a few minutes, take a fresh sample, spin & look for haemolysis in the plasma!

If anything, this would only pick up ABO incompatibility & I would not want my immune response tested in this way!!!

Seriously does anyone actually do this? I think it would lead to a false sense of security.

Also heard it called a 'biological crossmatch'

Donna is, as always, absolutely correct. There are other antibodies that would be detected this way; not least anti-Vel, anti-H (in a true Oh), anti-I (in some adult ii cases) and anti-PP1Pk in a pp individual.

This method of "cross-matching" (for want of a better term) also serves as a great way to boost the titre and avidity of such an alloantibody!

In this day and age, it should be banned under the Geneva Convention!!!!!!!!!!!

:eek::eek:

[adiescast]

That was my first thought as well. Doesn't this fall under "cruel and unusual"?

[Liz]

Oh my goodness, I do feel awfully embarrassed. However quoting the AABB Technical Manual:

Copyright © 2008 by the AABB. All rights reserved.

CHAPTER 20

Hemotherapy Decisions and Their Outcomes 579

"Other situations in which all units appear

incompatible include the presence of alloanti-

bodies to high-prevalence antigens, to multi-

ple antibody specificities, or both. If serologic

testing fails to resolve the problem or if the

problem is identified but time is not sufficient

for acquisition of compatible units, consulta-

tion between the transfusion service medical

director and the patient’s clinician is advised

to weigh the risks and benefits of transfusion

and to consider what alternative therapies are

suitable. If the need is sufficiently urgent,

ABO-compatible but crossmatch-incompati-

ble red cells may have to be given. Depending

on the alloantibody’s specificity (or the possi-

ble specificities that have not been ruled out),

incompatible transfusion does not always

result in immediate hemolysis, and the in-

compatible cells may remain in the patient’s

circulation long enough to provide therapeu-

tic benefit.

If time permits and if equipment is avail-

able, the survival of a radiolabeled aliquot of

the incompatible cells can be determined, but

that determination is beyond the capability of

most laboratories and is rarely needed. An

“in-vivo crossmatch” can be performed by

cautiously transfusing 25 to 50 mL of the

incompatible cells, by watching the patient’s

clinical response, and by checking a 30-

minute posttransfusion specimen for hemo-

globin-tinged serum. Such assessment does

not guarantee normal survival but can indi-

cate whether an acute reaction will occur. If

no adverse symptoms or hemolysis are ob-

served, the remainder of the unit can be

transfused slowly with careful clinical moni-

toring. If the transfusion need is life-threaten-

ing, RBC units may sometimes be given

without special testing, but the clinical staff

should be prepared to treat any reaction that

may result."

So since it is the AABB and recent I may add, what are your opinions on this???

Blush Blush !!!

Liz :-D

[Malcolm Needs ☆]

I can see from where you are coming LIz, but the situation they are talking about here is surely an in extremis situation, where you cannot wait until the Reference Laboratory has "had a go"?

[Liz]

We are a hospital-based Blood Bank. Annnnnnd there is no Reference Laboratory in the country

So yes it is only in extreme cases that this would be used.

Liz :-)

[Malcolm Needs ☆]

Which country are you in Liz?

[Liz]

I am in Lebanon at the American University of Beirut Medical Center, look us up: http://www.aub.edu.lb/

http://www.aubmc.org/users/index.asp

We are very good CAP, JCIA, and Magnet accredited

Liz

Edited July 28, 2010 by Liz

[Liz]

At this site you can go on a virtual tour of the Lab, BMT etc..

http://www.aubmc.org/users/subpage.asp?id=83

Liz

[Malcolm Needs ☆]

I am in Lebanon at the American University of Beirut Medical Center, look us up: http://www.aub.edu.lb/

http://www.aubmc.org/users/index.asp

We are very good CAP, JCIA, and Magnet accredited

Liz

Thanks Liz.

I was in no way suggesting that you and your staff are not good (far from it), I was just amazed that there is not a Reference Laboratory in the country.

If you do have a problem patient that you really cannot work out, what do you do? DO you send a sample to a Reference Laboratory outside the country, or do you have to rely on the in vivo cross-match?

I will certainly visit the website, but I will have to wait until I get home to do this. Our work "fire wall" is extremmely strict!

Thanks again for the information.

:D:D:D:D

[Liz]

Oh, I know you mean well, MalcolmJ. My friends abroad cannot understand how concerned I become when a new CAP inspection is coming up, they wonder how it is possible with the turmoil that they hear of, but what one hears is quite different from what actually is.

There can never enough time to send BB tests abroad; this is why I have been asking so many questions about the Elution and Adsorption. Incredibly, we have managed without it. But now we are getting stuck, there are more patients with abs, we have many regional referrals. I want to adsorb the Autos, identify them and identify any underlying Allos. I want to never again send out least incompatible. And never again to request that the in-vivo be performed. We have never had a problem, but I can push my luck only so much.

Dr. Garratty at the AABB meetings has talked a lot about the allos and autos, his conferences have helped me. But more so this forum has been overwhelmingly beneficial and teaching! J

I once performed a national extensive phenotype, and then a year later I had a patient with anti-e. So I went through my raw data, and guess who was e negative? Not from the North nor the South, but right here at the Dept: my Chair! So I drew from him and his sister the 2 units needed.

Whenever I need a rare type we call for more donors and test them. Usually the whole village from where the patient came will present to the Blood Bank.

Sounds like the dark ages, but we are our only source of Blood. That brings up another topic that I shall post in the Donor section: we perform weekly Blood Drives, except in summer. Where can one go in summer?? hmmmmm

Thanks for asking, I had a chance to carry on about myself…. J

Liz

[Malcolm Needs ☆]

Thanks for that Liz.

It sounds like you are doing a wonderful job under extremely trying circumstances.

I often forget how the other half lives, as they say.

Edited July 28, 2010 by Malcolm Needs
Missed a bit out.

[jayinsat]

Donna is, as always, absolutely correct. There are other antibodies that would be detected this way; not least anti-Vel, anti-H (in a true Oh), anti-I (in some adult ii cases) and anti-PP1Pk in a pp individual.

This method of "cross-matching" (for want of a better term) also serves as a great way to boost the titre and avidity of such an alloantibody!

In this day and age, it should be banned under the Geneva Convention!!!!!!!!!!!

:eek::eek:

The hospital system I work for here in the states use this procedure regularly. We use it primarily for patients with Warm Auto's where the xm was performed with phenotypically matche units that were serologically incompatible with neat plasma and least incompatilbe with adsorbed plasma. We draw a pre-transfusion plasma hemoglobin, give a test dose of washed prbc's and draw a post plasma hemoglobin 10 min later. If there is no significant change in plasma hgb levels, the entire washed unit is transfused.

From the stone ages,

James

[L106]

Hey, fellows....I didn't mean to imply that anyone who uses the "in vivo" crossmatch was from the stone ages.....I just personally haven't talked to anyone who has used it for many years.

The procedure may seem "barbaric" to some of you, but as I said, it's usually a "last-ditch effort". It's not that the "in vivo" crossmatch is taking the place of other testing. Rather, (as far as I know) it is used as an additional procedure after all available testing has been done and there is nothing more that can be done to procure compatible.

(If it helps your pathologist sleep better at night, so be it. No one wants to work with a tired, cranky pathologist!)

Donna

[Malcolm Needs ☆]

No one wants to work with a tired, cranky pathologist!

Donna

Oh, but Donna, so many of us do!!!!!!!!!!!!!!!

:eek::eek:

[L106]

Sorry, Malcolm! (Into every life, a little rain must fall....)

Donna

[Malcolm Needs ☆]

Sorry, Malcolm! (Into every life, a little rain must fall....)

Donna

True, true, but until now I never realised that England was a monsoon area!

Must be the Global Warming!!!!!!!!!!!!!!!!!

:eek::eek:

[Liz]

The hospital system I work for here in the states use this procedure regularly. We use it primarily for patients with Warm Auto's where the xm was performed with phenotypically matche units that were serologically incompatible with neat plasma and least incompatilbe with adsorbed plasma. We draw a pre-transfusion plasma hemoglobin, give a test dose of washed prbc's and draw a post plasma hemoglobin 10 min later. If there is no significant change in plasma hgb levels, the entire washed unit is transfused.

From the stone ages,

James

This is good to know, thank you James from the stone ages!

I like your humor too!!

This is Liz from the Dark ages

Edited July 29, 2010 by Liz
Forgot the blue colour :)

[Liz]

Hey, fellows....I didn't mean to imply that anyone who uses the "in vivo" crossmatch was from the stone ages.....I just personally haven't talked to anyone who has used it for many years.

The procedure may seem "barbaric" to some of you, but as I said, it's usually a "last-ditch effort". It's not that the "in vivo" crossmatch is taking the place of other testing. Rather, (as far as I know) it is used as an additional procedure after all available testing has been done and there is nothing more that can be done to procure compatible.

(If it helps your pathologist sleep better at night, so be it. No one wants to work with a tired, cranky pathologist!)

Donna

Hi Donna,

It was just some comic relief. I did appreciate and I do believe that it is a last ditch effort that we do to make sure that no immediate TR will occur; when I request it, I am very sure that I have done the maximum and in 14 years I only had one immediate reaction and the unit was stopped. It may have been cytokines there was no hemolysis. Frankly I feel safer and I sleep better J

Liz