For those that do not irradiate on site, do you keep an irradiated unit on hand or do you keep a regular cmv= fresh unit on hand?  We get a new unit every 2 weeks and we rarely transfuse infants but we have a unit on hand just in case

We keep 1 irradiated O Neg on hand for infant transfusions. We get a new one once a week. We also don't transfuse a lot of infants but we do have a NICU here and we will get an infant every couple of months that requires a couple transfusions.

The hospital that I retired from recently had an irradiator so we would get 1 O negative fresh CPDA1 CMV-, HbS- unit a week. I worked at a hospital where without an irradiator and we received 1 O positive and  1 O negative CPDA1, CMV- and HbS- unit both irradiated from the supplier. Most of the time we used the units on adults who required irradiated because we rarely used them.

As I am reading the AABB manual they speak about potassium release with units that are irradiated and stored for >1 day.  Did you look at this concern?

15 hours ago, kimblain said:

As I am reading the AABB manual they speak about potassium release with units that are irradiated and stored for >1 day.  Did you look at this concern?

That's why folks use 'fresh' units and also why irradiated blood gets a shorter outdate than the original (unless the current outdate is less than what you would change it to.

We routinely stock 2 O Pos, 2 A Pos and 2 O Neg Irrad units for oncology patients, so would have Irrad units available if ordered for a neonate. I think we average 1 or 2 neonate transfusions in a years time. Our irradiated units are rotated for restock about every 2 weeks and restocked when used. We do not stock CMV neg units. All our blood supply is leukoreduced, which is considered CMV safe. If we are planning a transfusion or have an anticipated birth of a baby who might need transfused we order a fresh unit or two.

1 hour ago, AMcCord said:

All our blood supply is leukoreduced, which is considered CMV safe.

I had a corporate transfusion service medical director who was uncomfortable with the term "CMV safe" so we were required to use the phrase "CMV risk reduced"!  I know it doesn't add anything to the discussion but when I read Ann's post the memory made me smile at the lengths some folks would go.

On 7/21/2021 at 1:35 PM, kimblain said:

As I am reading the AABB manual they speak about potassium release with units that are irradiated and stored for >1 day.  Did you look at this concern?

I've always thought that 1 week post irradiation would be the ABSOLUTE maximum for a unit to be used on a baby.  I actually thought 5 days was almost too long.  Anything longer and you do run into Potassium leakage problems that can make the unit dangerous for a Neonate.  We had a potassium overload reaction on a neonate once with only a small volume transfusion.  So - absolutely watch the length of time your units have been irradiated when transfusing to infants. 

We no longer have an irradiator on site and will be buying fresh, irradiated, CMV- units from our distributor for small volume transfusions.  I am worried that, over time (we only transfuse these babies about 2X a YEAR), the team will forget to move the leftover unit over to adults and will use too old of a unit on a baby.  I am retiring, so won't be here to watch out for it - so I will just have to worry.  I just can not figure out how to fix things so that 10 years from now, something that esoteric gets remembered by the poor tech stuck with it, for the first time in 5 years or so for them, in the  middle of the night!  Such are the nightmares of an old blood Banker!

Edited August 7, 20213 yr by carolyn swickard
additional wording

If this works - this is, I think, a proposed observational study to determine how standard Blood Bank practices may affect the transfusion of infants.  Someone is looking at the age of irradiated units and what it might mean to infant safety.  Interesting.

Does red blood cell irradiation and/or anemia trigger intestinal ...

https://bmcpediatr.biomedcentral.com › articles

 

 

 

by T Marin · 2018 · Cited by 6 — Our overarching hypothesis is that irradiation of RBC units ... The majority of premature infants receive transfusions for anemia of ...

In the UK, we have discovered that some of our donors have naturally high levels of potassium in their plasma, and have caused problems when used for transfusions in babies.  For this reason, we now test our paediatric units for high potassium, and any donors so identified are marked in our records as for use on adults only.

36 minutes ago, Malcolm Needs said:

In the UK, we have discovered that some of our donors have naturally high levels of potassium in their plasma, and have caused problems when used for transfusions in babies.  For this reason, we now test our paediatric units for high potassium, and any donors so identified are marked in our records as for use on adults only.

Just curious Malcolm, how high are your "naturally high levels of potassium"?  The top end of the normal values or would they be considered abnormal?  At what level is the blood considered not available for paediatric units? This is the first I've heard of testing units for potassium.

Hi John,

I am not absolutely sure, as this all happened just as I was retiring, but I have emailed a former colleague of mine who may know, but, if you put "NHSBT blood donors with high potassium levels" in to your search engine, you should get up a PowerPoint lecture that you can download with the long title of, "POTASSIUM LEAKAGE AND MEASURES OF THE RED CELL STORAGE LESION IN DONATIONS FROM INDIVIDUALS WITH FAMILIAL PSEUDOHYPERKALAEMIA", by Athina Meli, Maggie McAndrew, Amy Frary, Karola Rehnstrom, Christian J Stevens, Waleed M Bawazir, Joanna F Flatt, William Astle, Rekha Anand, Helen V New, Lesley J Bruce and Rebecca Cardigan, which may answer your question.

Thanks Malcolm, it did answer my question.  Apparently while their blood is circulating these people maintain normal levels of K+.  It is only upon storage that they leak the K+ at higher levels than normal. It appears to be a genetic cell membrane "defect" 

"Familial pseudohyperkalaemia (FP) • dominantly inherited, asymptomatic • characterised by an increased rate of leakage of K+ from red cells at refrigerated temperatures • usually caused by the minor allele of a non-synonymous single nucleotide polymorphism (FP SNP; rs148211042; R723Q) in the transporter gene ABCB6 (ATP-Binding Cassette, subfamily B, member 6) • codes for a red cell membrane transporter protein • raw chip measurements from a screen of the UKBioBank suggested ~1:400 of the UK population have the FP SNP"

"Study – identified FP individuals • screening of the National Institute for Health Research Cambridge BioResource (NIHRCBR) – identified 16 out of 8712 individuals with the FP SNP. • 2 more individuals with the FP SNP were identified when clinical cases of unusually high K+ levels were reported in RCC units that they had donated – characterised in Bawazir WM, et al. 2014"

Thanks again, 

On 7/21/2021 at 12:35 PM, kimblain said:

As I am reading the AABB manual they speak about potassium release with units that are irradiated and stored for >1 day.  Did you look at this concern?

For us, we don't consider the unit fresh if it's been irradiated more than 24 hours but only if the transfusion is >20cc/kg or push transfusion.  Those get rotated back into normal stock and used for all patients including neonates as long as the volume is <20cc/kg.  

We do about 6 NICU transfusions/year. We routinely keep a fresh, CMV=, IRRADIATED unit on hand which is replaced every week. That unit is for emergency transfusion only in the NICU. If the situation is not critical, we order a fresh unit for the baby with satellite bags attached. It takes our supplier about 90 minutes to get that unit to us. The majority of our babies can wait. If it is an emergency, then we give the best product we have. The neonatologist says "we can treat hyperkalemia but we can't treat death."

On 7/16/2021 at 3:19 PM, kimblain said:

For those that do not irradiate on site, do you keep an irradiated unit on hand or do you keep a regular cmv= fresh unit on hand?  We get a new unit every 2 weeks and we rarely transfuse infants but we have a unit on hand just in case

We get an Irradiated/CMV Neg, O Neg weekly - only have infant transfusions once every year or two.  They may not be the freshest units but they will do in an emergency, until infant is transferred to NICU hospital

I found this article today discussing the risks of transfusing blood with higher K+ levels in infants.

MINI REVIEW article

Front. Pediatr., 29 October 2021 | https://doi.org/10.3389/fped.2021.765306

We use O Neg, CMV neg, irradiated units for our babies but we wash them with a blood washer (an old COBE 2991).  I know...we are dinosaurs and yes, I am FDA inspected because of it.  Washing removes the potassium and anticoagulant (which can cause citrate toxicity in small premature infants).  

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.

Although I agree with @Neil Blumberg regarding CMV seronegative blood we had 2 heart transplant candidates patients in our Cardio Thoracic ICU that were originally CMV negative by pcr and came up CMV positive while inpatients and both had severe infections.  Our infectious disease physicians decided it was due to the multiple blood and platelet transfusions (both were put on ECMO and had multiple surgeries) and now they order CMV seronegative products on all heart transplant candidates regardless of CMV status and those with DiGeorge Syndrome (due to their immunodeficiency - per my med dir not CTICU).  They refuse to listen to reason or science and they didn't even bother testing any of the staff, parents, or other people working in the unit.  (This is me rolling my eyes).  Our bone marrow and stem cell transplants don't require CMV negative products but the kids in CTICU do.  

As far as transfusing pRBCs, we wash (and waste) a considerable amount of RBCs for any <4 months old, < 4 kg neonate that is also going through open belly surgery, open chest procedure (not on CPB), kids with K issues that have current elevated K+ levels, HUS due to Strep pneumo (and before ID of the cause).  Our heart room washes the blood during CPB so we don't have to.  We also have a <6 day old RBC, <24 hour irradiated, policy to keep the K down if >4 months but <1 year or >4 kg but it's for surgeries and any transfusion >20cc/kg.  Most normal, non-surgical transfusions for neonates are done with irradiated, CPDA-1 or AS-3 RBCs but the volume is normally 10cc/kg at a rate of 2-5 mL/kg/hr.  In order to keep the patient on the same unit as long as possible we normally start with 6-10 day old unit as well.  I really don't want to switch to washing for all neonatal transfusions.  Our wastage rates are already too high.

To clarify, we sterile dock a packed cell into quads and wash one quad at a time when a transfusion is needed.  We try to dedicate one packed cell to an infant (which decreases exposure) but will use a unit for more than one infant if needed. This helps prevent wastage. Our overall wastage is very low here.  Also, we don't transfuse too many infants at our facility (maybe 1 baby per month).  Really premature/sick infants are transferred to a local children's hospital for a higher level of care. 

Sounds like the source of CMV in your intensive care unit likely were visitors (probably family members) or staff with new CMV infections or reactivations of previous CMV infections.   The chance that there would be two transfusion transmissions in the same unit is extraordinarily low. As you say, the triumph of belief over data/science. CMV is ubiquitous in our society which is why as many as 70-90% of us are CMV seropositive.  CMV testing is probably largely useless at preventing infection when transfusions are leukoreduced.  I think most of the early literature may have been confounded by community acquired/person to person transmission.  Just wasn't considered at the time.

16 hours ago, BldBnker said:

To clarify, we sterile dock a packed cell into quads and wash one quad at a time when a transfusion is needed.  We try to dedicate one packed cell to an infant (which decreases exposure) but will use a unit for more than one infant if needed. This helps prevent wastage. Our overall wastage is very low here.  Also, we don't transfuse too many infants at our facility (maybe 1 baby per month).  Really premature/sick infants are transferred to a local children's hospital for a higher level of care. 

What instrument are you using to wash your red cells?  I've never washed less than 250mL.  Any chance you could share your procedure?  

Sonya Martinez, it is an old COBE 2991 (I think they are now made by Terumo).  It is programmed to wash a whole unit, a pedi/quad unit, or do a 2-L wash for IgA deficient patients.  Our machine is probably at least 30 years old.  We just spike the unit and spike a 1 L bag of injectable saline using the wash bags that are used on the machine.  The machine takes care of it! 

 Here's the link:   https://www.terumobct.com/2991

To wash less than 250ml RBC on the COBE/Terumo (I think at one point it was Gambro too), you will need to adjust the setting for Superout Volume and potentially increase volume of either saline or Plasmalyte A (either can be used) since the volume of the COBE bag is 650 ml.  As the volume of RBC decreases, the volume of wash solution increases.  Depending on the age of the COBE, it is either programmed electronically or with pegs.