Let's talk a little about transfusions in children....
So, what are the top three indications for pediatric transfusion?
1. Acute hemmorhage
2. Bone Marrow Failure
3. Symptomatic chronic anemia (sickle cell anemia, diamond-blackfan anemia, or thallessemia)
Transfusion is something most doctors try and avoid, for two reasons:
- Children are generally most robust than adults.... their systems can easily compensate for blood loss of up to 25% and remain asymptomatic. They tend to not have any of the underlying conditions that complicate adult cases. If the patient isn't symptomatic, why risk transfusion, and the associated risks of iron overload, and possible infection or reaction?
- There tend to be other treatments available for most conditions with symptoms; EPO for renal insufficiency, colloid solution for blood volume problems, or oral iron for IDA. Other than acute hemmorhage, there tend to be other viable options instead of transfusion.
I've seen hospital procedure vary a lot, around those two golden principles. Some hospitals saline wash to remove preservative solution just before giving the unit, some do not. Some hospitals insist on across-the board irradiation of the units as well, to cover the special cases such as new oncology patients with unconfirmed diagnosis. Others treat older adolescents like adults. One endorsed method was to always have a fresh CMV negative unit available, that would be hand washed to remove the preservative and then given out with a form to denote how much of the unit was actually given. Another method was to divide the single PRBC unit into three or four bags, to be given out to the patient as needed over the twenty four hour period
(thus reducing the number of donors the child is exposed to, as well as enabling smaller transfusions.)
Both have solid reasons....Doctor's who choose to go with a single donor unit, are typically concerned about minimizing the amount of donor exposure. Aliquots are taken off the sterile unit and used for the amount of permitted storage. The rationale of the traditional choice of fresh packed cells involves trying to side step the possible buildup of potassium(during unit storage) being passed on to the patient(usually more of a concern when patient is in the first four months of life). Let's take a look at this concern.
After the full 42 days of storage, extracellular plasma potassium levels in a single unit of packed red blood cells are shown to be 50mEq/L. I agree that giving the whole unit at once on the last day of possible use would decidedly be too much of a system shock to a neonate, and therefore unsuitable. Thing is, most neonate transfusions we give 15mL/kg. For small amount transfusions(<15mL at a time), the age of the blood is not a concern, as maximum potassium levels would be only 0.015mEq/L (tiny amount) of potassium per transfusion. (See Nelson Pediatrics 18th Ed 2007, pg. 2057). Anything over 25mL of older blood is getting a bit more dicey, and shoule be avoided. That said, non-neonatal pediatrics
can handle the 50mEq/L maximum possible amount of potassium, as can adults.
In short, neonate transfusion requirements and pediatric transfusion requirement are different. Not all hospitals denote that, instead preferring to stick to the more stringent newborn guidelines for all. As blood banking protocols improve, we are working on tailoring out unnecessary product preparation while ensuring that the proper precautions are still in place.
