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Perhaps I'm a little naive, but I find some of the "old time" logic somewhat illogical. I appreciate that a unit of red cells being transfused would potentially be "cold" - 1 - 6 C at the start of infusion, i.e., might cause a cold-agglutinin issue, but almost immediately, the infused portion would equilibrate to the temperature of the circulating blood. Additionally, the unit itself would start to warm-up to room temperature. Certainly additional problems could arise from "by-pass" procedures, but are the devices\pumps "cold" - 1 - 6 C ?? I suspect they operate at room temperature, nowhere close to refrigerator temperatures. After all that rambling, I meant to say that I don't why anyone would test "cold autoantibodies" at temperatures below that of typical (surgical) rooms. However, I'm sure there is a a whole library of circumstantial, anecdotal evidence supporting such extreme testing protocols.

We used to use that same procedure when we were doing open heart surgeries and the patient was on bypass. If our antibody screen was positive at 4 degrees, we would test at 10, 15, and 20 degrees - maybe even 30 degrees if the room temperature incubation was positive. Whatever the thermal range was, we would then do an antibody ID (who cares) and titer at that temperature. We would also include a test at 4 degrees using a 20% suspension of the patient cells to see if there was agglutination after 30 minutes. We in the blood bank were very happy when new surgeons were brought in who no longer wanted that testing -- working on beating hearts and doing mini valve replacements, etc. has helped us immensely.

Well, if you follow Petz and Garratty, the "bible" of auto-immune haemolytic anaemias, first of all performing a titre is a total waste of time as, although most clinically significant "cold" auto-antibodies are high titre, this is by no means a universal n, and so, if you ignore an antibody because it is low titre, you could be in trouble (more to the point, your patient could be in trouble). Secondly, determining the specificity of the antibody is even more of a waste of time. If it is an auto-anti-I, are you going to give adult ii blood? No. If it is an auto-anti-H, are you going to give Oh blood? No. If it is an auto-anti-HI are you going to give blood from a donor who is OhAND an adult ii? Well, if you can find such a donor anywhere in the world, you are a better serologist than anyone who has yet existed. Is the thermal amplitude useful? You bet your bottom dollar it is! The human body will never reach 4oC or 22oC, so performing tests at those temperatures is a waste of time, BUT, the extremities (fingers, toes ears, nose, etc) can go down as far as 30oC., and this is why Petz and Garratty recommend that tests are performed STRICTLY at 30oC, as, if the antibody reacts at 30oC or above, it is clinically significant as an auto-antibody. Tests at 37oC are only really useful if you are cross-matching blood for the patient, in order to see if there are any clinically significant alloantibodies present in the plasma.

We keep them until the monthly invoice comes and then they are discarded. All documentation of unit receipt and final disposition is in the computer system.