We have been approached by our Perfusion team to do a Cold Agglutinin assessment for every patient going on bypass. What test do you do, if any, and at what temperature? The literature suggests if it's active at room temp, it may be significant, but with new techniques they are using in the Perfusion arena, they are saying that they are seeing alot more "clumping" in the bypass tubing with patients on whom we have no detectable cold agglutinins by our routine testing. We currently test by automated Capture Methodology, and perform the bulk of our xm's by electronic xm for all who qualify. Typically, if there is a strong cold agglutinin, we get errors on our ABO testing by automation. Thanks for your input!