Emergency Transfusion O pos or O neg?

[lalamb]

I thought an O neg person coulf get O pos units just once in their life, then they develope anti -D.

So how would one know if your emergency guy had anti-D from a prior emergency transfusion?

We give O neg 1st, then work up the blood, giving type specific/compatible.

We have had a few massive bleeds where the pathologist had made the decision if and when to give O pos, so we don't deplet our inventory. One was a woman of child bearing age, but was in bad shape. We got the go ahead to give O pos, but it wasn't needed.

[jcdayaz]

I thought an O neg person coulf get O pos units just once in their life, then they develope anti -D.

So how would one know if your emergency guy had anti-D from a prior emergency transfusion?

We give O neg 1st, then work up the blood, giving type specific/compatible.

An O Neg person who receives O Pos blood has a good chance of developing an Anti-D. It is not guaranteed. I agree with you..start with O neg (even in Males) until you can determine the possibility of massive transfusion need. Then you have to determine your stock status of O Negs, etc etc before more decisions are made.

[tbostock]

I thought an O neg person coulf get O pos units just once in their life, then they develope anti -D.

So how would one know if your emergency guy had anti-D from a prior emergency transfusion?

We give O neg 1st, then work up the blood, giving type specific/compatible.

We have had a few massive bleeds where the pathologist had made the decision if and when to give O pos, so we don't deplet our inventory. One was a woman of child bearing age, but was in bad shape. We got the go ahead to give O pos, but it wasn't needed.

Massive bleeds, especially when due to trauma, are a little different. Statistically, trauma is a "guy thing", so most trauma victims are young healthy males who have never been transfused. They've done studies about Rh Pos blood given to massive bleeders and the rate of making Anti-D is less than 10%. Certainly, if you can spare a couple O Negs, you should always start with that...but once you identify that it's a male, and he's massively bleeding, you can pretty confidently get him quickly into Rh Pos.

[jcdayaz]

Massive bleeds, especially when due to trauma, are a little different. Statistically, trauma is a "guy thing", so most trauma victims are young healthy males who have never been transfused. They've done studies about Rh Pos blood given to massive bleeders and the rate of making Anti-D is less than 10%. Certainly, if you can spare a couple O Negs, you should always start with that...but once you identify that it's a male, and he's massively bleeding, you can pretty confidently get him quickly into Rh Pos.

Thank you! I couldn't remember the %.

When the blood is going in as fast as it is coming out it is relatively uncommon for an Anti-D to be formed. The "foreign" blood..ie..Rh pos is not in the recipient's system long enough to stimulate an immune response.

Any ideas on how to side-step a BB Medical director (Pathologist) who is totally opposed to switching a person to Rh Pos even in extreme trauma cases? We have to get Pathology approval prior to switching a patient. Our BB Medical Director told the last Tech who called him attempting to switch a male patient to Rh pos units to use O Negs until our inventory got down to 2 and then he had approval to switch! Our normal(desired) inventory of O Negs is 20.

[tbostock]

Sidestepping a Medical Director...hmmmm...that's a concept...haha

We have a Massive Transfusion Protocol which outlines when the switch happens (automatically) so that the Medical Director doesn't have to approve it each time. The Medical Director, as well as Transfusion Committee and the Medical Staff approves the policy, then you're good to go.

If your Medical Director needs more info, there are great articles from Dr. Hess at Cowley Shock Trauma in Baltimore about massive transfusion, using Rh Pos for trauma patients, etc. They are the "gold standard" down there, they do awesome work, lots of it gleaned from the battlefield in Iraq/Afghanistan.

[pluto]

has anyone experience of transfusing RhD Pos red cells to RhD Neg recipients in routine scenarios

once you exclude transfusion dependant recipients and females under 60 I am considering all males / females over 60 , males possibly a bit younger ?

aim is to reduce quantity of O Neg stocks received , interested in protocols elsewhere and sensitisation rates etc

Is choice also based on quantity requested ie if 2 or less give Rh Neg if 3 or more give Rh Pos

some good refs in this thread , thanks all

[Malcolm Needs ☆]

Back in the day, when D Negative units were ALWAYS short, before the NHSBT got their act together with calling in donors, it was quite common practice for D Negative patients as you describe to be given D Positive blood. There were no immediate or delayed clinically significant sequelae as far as I know, although, undoubtedly, some did go on to develop a nice, healthy anti-D!

:shocked::shocked:

[Deny Morlino]

interested in protocols elsewhere and sensitisation rates etc

At the spring Technical Advisory Committee meeting held by our ARC we watched an interesting presentation on this exact topic. The key point as far as I was concerned was that the original studies regarding sensitization rates (resulting in 80% sensitization) were performed on healthy volunteers. More recent studies have shown the sensitization rate to be closer to 22%. The presentation title is Type O Negative Red Blood Cell Utilization: Preserving this Rare and Lifesaving Resource and is available through American Red Cross's Success program. Not plugging for them in any way, but it was eye-opening the differences reported in the more recent studies.

[Mabel Adams]

During a shortage of O negs some 10 years ago we had to convert a surgery patient that was bleeding to O pos. When they finished, they brought back the unused blood and had given only one of the O pos units. We happened to test him again a few months later and he had made a nice anti-D. As I recall he was a somewhat elderly fellow. Anyway, that was a fairly routine use of Rh pos in an Rh neg patient and although he didn't have any immediate problems, he certainly was still immunocompetent enough to make the antibody. The immunosuppression they quote in the trauma statistics did not hold true in this case.

[AMcCord]

As it is a deviation from your written policy/procedure, you could have asked them to sign for it. Whenever you ask an MD to sign for blood, we have discovered, they tend to think twice & usually go with what we tell them. That or we can sick our pathologist on them.

Good idea!

[Likewine99]

If you can get some intervention from your trauma medical director you might be able to "side step" your pathologist. The trauma medical directors are "in the know" re: massive tx protocols.

They can probably refer you to some of their resources and journals that could help you make an evidence based decision on what type of blood to give to your trauma patients.

Tbostock has stated very well the current thoughts on trauma patients. In a true trauma situation there is the possibility that the pts immune system "shuts down" and the blood is passing through them so fast that they may not make an anti-D. Making an anti-D is often the least of the worries in a massively bleeding pt.

[Tonyd]

At the spring Technical Advisory Committee meeting held by our ARC we watched an interesting presentation on this exact topic. The key point as far as I was concerned was that the original studies regarding sensitization rates (resulting in 80% sensitization) were performed on healthy volunteers. More recent studies have shown the sensitization rate to be closer to 22%. The presentation title is Type O Negative Red Blood Cell Utilization: Preserving this Rare and Lifesaving Resource and is available through American Red Cross's Success program. Not plugging for them in any way, but it was eye-opening the differences reported in the more recent studies.

Thanks for this info Deny - unfortunately the site won't let me log in as I don't have a Hospital Red Cross number (or something like that), being in the UK. Does anyone have the pdf on file, that they wouldn't mind sharing ?

Best wishes

Tony

[Deny Morlino]

Some of the Red Cross folks from my area check in here from time to time. Trisha if you read this is there anything that can be made available for this request? I will try to reach her via e-mail too.

[ejsommers]

I understand the theory behind the O Pos for males and females 55+ but I don't like it. We have the same policy here. I have had 3 instances of patients with Anti-D where we sent up O pos blood. Luckily, I was able to intercede before any units were transfused. I think you should switch over the heavy users to O pos but O neg should be initially sent to the ER until a negative screen can be determined.

Just my opinion but I know it's not the official standard.

[ejsommers]

I wouldn't want to be that patient that came in the door WITH the Anti-D

[Mabel Adams]

But the majority of trauma patients (85%) will turn out to be Rh pos. Hate to waste the O neg on them. I used to worry some about the elderly ladies because some of them might have an anti-D from 50 yrs ago, but elderly ladies are a really small proportion of trauma patients and as we get more years past the introduction of RhIG in 1968, those numbers should decrease. People born in 1945 would have been 23 then so that seems like a reasonable midpoint age. Very conservative would be 1950 or 55 due to very young pregnancies and not all drs being up on the latest issues so not giving RhIG when it first came out. Women born in 1955 would be 56 and those born in 1945, 66 so the problem should be slowly dying out. Men transfused in WWII also might have been given Rh pos blood but they are getting quite elderly now.

If someone is bleeding fast enough to need uncrossmatched blood and you give them a couple of units of D+ before you ID the antibody they are probably not going to be too much harmed by it. The Rh system does not fix complement so almost all destruction will be extravascular and they can only destroy the blood that hasn't bled out which much of the first units given will.

I had to give an emergency patient with anti-e incompatible blood once and she showed no signs at all except a pos DAT afterward. We gave her some e neg units too afterward--I think 2 e+ on her way to surgery plus about 4 e- later that day and another one or two the next day. They have protocols for giving incompatible blood to liver transplant patients that should provide us some comfort. What you really don't want to do is use all your O neg first so you have to switch to O pos at the end and leave them full of O pos. Better to 'save the best wine for last' and give the incompatible stuff first--just not ABO or probably Kidd system if you can help it.

I have been reading studies on uncrossmatched blood and there are just no cases of immediate hemolytic transfusion reaction in the literature. The one reaction reported was a day or so post-transfusion and may have actually been to blood given the week prior. The patient had no symptoms but did have a pos DAT and some change in chemistry values--can't remember what.

Statistically 15% of trauma patients would be Rh neg; 4% might have an antibody (any specificity). Let's say half of the antibodies we find these days are anti-D (but I think it is less). Those facts give you 0.3% odds of incompatibility. So if you do 1000 uncrossmatched patients in a year, you might see 3 such cases but at smaller places it will take us 50 years to see that many. If the titer isn't too high, that will reduce the risk also. It does mean it is important to check patient Antibody history early in the process--this is as true for anti-E as anti-D since you can switch to Rh neg units and be pretty sure they will be E neg.

If your trauma population is mostly young males that shoot each other they are not too likely to have had prior transfusions. There was also some supposition once on one of these discussion groups that the reason the trauma patients seem less likely to make anti-D is that the studies were done in big-city hospitals where a lot of traumas are due to gang violence. These populations had a high proportion of African Americans who inherit anti-D by a different genetic mechanism than most Caucasions do. Someone speculated that this population may be less likely to make anti-D due to these genetics. I don't know if there was any evidence of blacks making anti-D at a lower rate in other contexts. Interesting variable to keep in mind. Maybe someone could study it and prove or disprove it.

Oh, boy, major brain dump. Sorry to ramble on.

[Malcolm Needs ☆]

Superb post Mabel!

[Mabel Adams]

Please correct my post above to state that African Americans inherit D negative status differently than Caucasions. So far I have not heard of someone inheriting an antibody. Must proofread better...

Malcolm, you are too kind. Careful, you will get me started again.

[mrmic]

From a Level I Trauma Center, the only exception we will make is for a young female of child bearing age <40 yrs. Otherwise, a trauma is a trauma and usage should be expected as high we issue group O red cells. When we find that the patient is Rh Negative, will will switch back to Rh neg during the last units when the patient has slowed down. Some of the auto, stabbing or gunshot traumas can use 50+ products in a short amount of time, many 100+, so depleting the community's Rh negative supply for these patients may not be considered warranted. Good communication and policies between the BB and ER/OR are a MUST! But once it is established it works well...

[clmergen]

Thanks for the post Mabel. I just went from a Level I trauma center to a smaller community hospital. The concept of using Rh Pos blood for any Rh Neg patient or Trauma is completely shocking to most of the technologists here. You have done the math I needed to help convince them that we won't be harming a patient. We just gave an Oneg 72yr male about 12 units of Oneg red cells in less than 24 hours. What a waste of Onegs. Now if I could just get the computer system to allow it (separate post to be made soon requesting help).

[Mabel Adams]

And remind your techs that if they are the least bit remote, they could end up using all the O neg on that older man and have none left for the OB that is Rh neg and starts to hemorrhage. That would cause actual harm.

[macarton]

We have given a large number of Rh positive units to Rh neg over the years due to emergencies or shortages. I can only remember 1 coming back in with an Anti D.

We had a series of tornados to wipe out a couple of towns in NW Alabama on the 27th of April. We are the largest hospital in this part of the state. Several trauma cases came into the small hospital nearest the area and the critical patients were shipped to us, Huntsville Hosp and UAB. Our smaller sister hospital was scolded because they refused to send their 6 O neg's to the hospital nearest the destruction. They were also transferred patients. The local command center said that they should be the ones to make a call when our O neg's & our sister hospital would be sent. Our administration has nixed that.

[Marilyn Plett]

Most regions in the US use O negative RBCs in excess of the proportion of O negatives in the population. This puts an enormous burden on O negative donors to donate as frequently as possible, and hospitals should use those donations as wisely as possible. Transfusion services owe a tremendous debt of gratitude to those faithful O negative donors.

[Mabel Adams]

http://www.redcrossblood.org/hospita...ate-newsletter

See the March/April 2011 newsletter on this ARC site for a nice description by the Medical Director (and occasional poster on these pages) of why it is appropriate to use Rh pos blood for emergency transfusion.

[Mabel Adams]

macarton, if you have any more information about your tornadoes it would be great if you added to the thread "Disaster Experiences Shared" in Hot Topics from January. Maybe we can all be better prepared for an influx of patients or a lack of resources by learning from others' experiences.

And Marilyn, isn't it amazing that an entire treatment option (and our profession) exists simply due to the altruism of blood donors. Makes you feel better about the human race.