Neonate with Positive DAT due to maternal anti-A

[John C. Staley]

We have been forced to switch from Adsol RBCs to CPDA-1 for our neonates (long story and not important right now). Our SOP had been to give type O RBCs to any type A or type B neonate with a positive DAT due to maternal anti-A or anti-B. With ADSOL I wasn't concerned due to the removal of virtually 100% of the plasma. With CPDA-1 RBCs there is at least 20+% of the plasma still on the RBCs. I consider giving these babies type O as just adding more fuel to the fire. If we were to give them type specific RBCs the anti-A/anti-B would very quickly be removed but by providing type O we are just adding more anti-A/anti-B with every transfusion. The corporate clinical pathologist over transfusion services will not even consider anything but type O for these babies. What are others doing and can you see the logic in my argument or am I so far out in left field that it makes no sense to anyone but me?

Thanks

John

[adiescast]

What does the infant's back type look like? If they do not have "free" antibody in their plasma you may be worrying about nothing with giving type specific.

We still give all type O Adsol units, so the issue isn't big for us. I have a statement in my procedure about performing back types to detect free maternal antibody in any infant that is to receive type specific red cells.

NEONATAL.doc

[John C. Staley]

:oops: Actually, most of the time we have discovered the maternal anti-A or anti-B by taking the back type through AHG and not a positive DAT. I failed to mention that in my original post. Basically, as long as we can detect the anti-A or anti-B in the babies serum we are forced to give them type O which in turn adds more anti-A & anti-B. This just does not make any sense to me but when the discussion comes up everyone looks at me like I have three heads.

[Melanie]

We give group O to all our neonates. It simplifies collection and processing and making of aliquots. It is also safer, since most transfusions are based on one type. We use leukoreduced CPD irradiated units.

[John C. Staley]

I'm sorry but I fail to see the "safer" argument for giving all neonates type O blood. Easier, yes; convenient for the staff, yes; safer, NO. How can giving them incompatible plasma possibly be safer? I'm dealing with babies that weigh as little as 14 ounces. Their total blood volume is so small any amount of incompatible plasma can not be good.

I do appreciate the input and it is interesting to see how different facilities handle the same problems.

[adiescast]

Have you considered using washed or deglyced blood for your neonates? One institution I worked at deglyced an O neg unit once a day and gave to all the neonates from that unit for the day. (I don't know if they still do it that way - I've been away from there for years!) The problem with that process is more donor exposure for each infant, but it eliminates the plasma problem.

Are you seeing infants develop a positive DAT after giving them blood from your type O units? If you are not, then you may not really have a problem. What actually ends up happening with the infants you transfuse regularly is that you replace their type A or B or AB blood with type O, so the antibodies don't have much effect on them. If you see positive DATs regularly after transfusion, then you are causing a problem and your policy needs to be revised. I'm sure you do not currently do DATs routinely on infants after transfusion, so you would have to experiment with it. This would also give you ammunition when you make your case with the people who think you have three heads (sometimes three heads are better than one! )

[John C. Staley]

This is primarily a deep philosophical discussion. The corporate clinical pathologist will never budge on this. Deglycing or washing are not options. We do not give type O cells to non-type O babies unless they already demonstrate anti-A or anti-B from mom so having a DAT develop would not be an indication. Also, we seldom if ever repeat testing during the initial 4 month neonate period.

The babies are still producing their own A or B cells so the addition of the antibodies via transfusions of type O RBCs will continue to destroy them.

This is probably one of those "no right answer" things that make for long and delightful discussions.

Thanks for the input.

[Tricia]

I think most people are looking at going from CPDA to Adsol for babies and it seems you have taken a step backwards in going from Adsol to CPDA. Is there any way to change back to Adsol based on your antibody argument?

[John C. Staley]

A step backward, with out a doubt!! The decision was made at the corporate level and I won't get into the politics of that but currently I can't get the decision makers to even listen to the argument let alone consider it. I just gave my medical director a proposal for a study. I want to monitor DAT for the babies receiving incompatible plasma during RBC transfusions if their initial DAT is negative. Maybe a DAT converting from neg to pos due to RBC transfusions will get some attention.

Thanks for the input.

[Sandy L]

Our transfusion service supports a 60 bed level-3 NICU and our standard red cell transfusion is CPDA1 leukoreduced and group O. We do get some directed donor units other than group O so test the infants plasma for the corresponding anti-A and/or anti-B by indirect antiglobulin test in those instances. If we have transfused group O Red cells after the initial test for anti-A or -B and then get a "non-O" unit we repeat the test. We frequently see maternal anti-A or -B in the indirect antiglobulin test or causing a positive direct antiglobulin test. We have yet to see a DAT or IAT become positive after transfusing group O red cells.

[John C. Staley]

Sandy,

How often have you actually retested a baby once you've started transfusing them? As long as there are no antibody problems or any other reason to retest you don't have to until they exceed 120 days old.

Thanks for the response.

John

[Walter]

Start with a literature search of instances where passive transfer of red cell or white cell or platelet antibody caused harm to a neonate. Journal articles go a long way with pathologists.

You won't have a convincing physical argument until you transfuse CPDA-1 red cells from a donor with a high titer, hemolytic anti-A,B.

[Sandy L]

John,

In answer to your question, no, this is not a frequent occurence where we would retest an infant after we have started transfusing, perhaps once or twice a month. Most of our infants start on group O and stay there, so it only happens when we switch an infant back from group a group O to a non-O unit.

Sandy

[hunb]

It is extremely difficult to obtain CPDA-1 blood units in our region as our local blood center does not collect these units and neither does their secondary supplier of blood. Also, it seems to me if you are worried about the presence of anti-A and anti-B in the units than you should remove the additional plasma by expressing the unit after centrifugation (shortens the lifespan of the blood). Another alternative is to split the unit into Pedi-paks, then centrifuge, then express plasma/additive, and add back type AB pedi-plasma to maitain a HCT of 70-80%.