JEMarti

Getting a second blood draw is very problematic to say the least. You've already pointed out that having 2 draws in close proximity to each other is virtually like having one draw into two tubes. Then there are the issues of what to do for presurgical patients and are you going to require them to come in an additional time for a second blood draw? If you have a NICU are you going to require it for those patients? (At my institution we give Rh POS units to Rh Pos babies so you wouldn't want to be giving it to an Rh NEG baby by accident) Are you going to demand two blood draws for trauma patients and if so are you going to give O Negs until you get them? And perhaps most disturbing should be the fact that in collecting two specimens you are taking an oficial position that transfusing off of one specimen is not safe and therefore if you allow any exceptions to that rule you are exposing yourself to a large amount of legal liability. You are setting up a possibility of having two standards of treatment and you are making a policy that says that having two specimens is the safer of the two. Even if you do not have a case of mistransfusion any transfusion complication could become an opportunity for a claim of negligence. I understand the impetus for having a second confirmatory draw, but it is logistically very difficult to implement. I would be very reluctant to set up two standards of care if I could avoid it.

There reagents are OK. With the notable exception of their Anti -Jka and Jkb. The reactions are weak enough that you can miss a weak positive on a heterozygote and we no longer use them for that reason. Also the Fya requires a 30 minute incubation which is much longer than the competition and I am not clear that they have an anti-Fyb. Also be careful with the volume size of their rare antisera. Their volumes are small so you will go through the vials much faster. Their pricing is still better than Ortho or Immucor but not as much as it appears at first glance.

This subject drives me batty. When one considers how apheresis platelets are leukoreduced one realizes that those products contain nearly zero red cell contamination if collected properly. Trima and to a lesser degree Amicus platelets should be essentially free of RBC's (Haemonetics platelets can have more, but with the US plt customers of Haemonetics so few you can count them on your fingers this doesn't matter much). Far more likely, is RBC contamination in plasma. With the drive to produce larger volumes of plasma, both from male donors for FFP and female for recovered plasma labs are cutting it very close on the collections. I have seen far more bloody plasma units than platelets in the last 5 years. In fact I cannot remember the last bloody platelet I saw. But we did have a 21 YO female who received 6 units Rh POS plasma last year. She was O NEG and developed anti-D and anti C. She received 4 units of O NEG RBC in addition to the plasma and nothing else. Unfortunately, our lab pushes RhIg on Rh NEG recipients of Rh POS plts but does nothing about Rh POS plasma recipients. If the risk is significant enough to give RhIg for the plt population it is certainly high enough for the plasma. The practice of giving it for plt recipients is borne of how platelets were manufactured a generation ago. We need to reassess our practices, but unfortunately are slow to do so.

I had a harassed night shift tech snap after multiple phone calls and tell the nurse to come and get the fresh frozen plasma for her patient. When she arrived she asked how she was supposed to transfuse the block of frozen plasma he handed her. He told her that if she wanted to stop calling him he could actually do his job and thaw it for her. Needless to say his call volume dropped dramatically after that.

Despite the fact that most of our plasma never makes it past 24 hours (and we keep 24 units thawed for stock), we go directly to the 5 day outdate.

We handle all factors and RhIg (excepting WinRho) and skin. Factor VII requires Med Director approval (ie resident). Approval for F7 is pretty well controlled and the Blood Bank is able to turn around requests rapidly even on third shift.

If you wanted to differentiate IgG and IgM antibodies you could DTT treat the plasma to get rid of the IgM and then you would only see the reactions from IgG. We saw the same issue when we went to solid phase. We saw a number of antibodies that did not react in solid phase or in the tube with LISS but they did react in PEG. We concluded that it seemed to be more an issue of the LISS rather than solid phase since the solid phase is a LISS technique. I think that ultimately you need to make your peace with the fact that every medium has it's faults and unless we want to screen using multiple media we will always run the risk of missing something.

There is a difference between manufacturers in how their droppers dispense. The first issue is the angle the tech holds the dropper. I have tested the number of drops dispensed from various vials of Ortho, Immucor/Gamma and Biotest antigen typing antisera. All three show a significant difference in the number of drops dispensed. Ortho and Biotest run approximately 40% fewer drops if the tech holds the dropper at an angle. Immucor Gamma runs about a 20% difference. The issue with Biotest reagents is that they contain only 2ml in many of their products so it feels like you are blowing through reagents. The second issue is whether the tech follows the IFU. Most IFU's call for one drop of sera with one drop of cell suspension. Techs trained back in the day before many of the newer, stronger reacting clones often will drop 2 drops instead of one. Dropping 2 drops more than negates the advantage of holding the dropper upright. None of the manufacturers has a dropper that is right on 50ul. They are all slightly more than that. The closest I have seen is consistently in the mid 90 drops from a 5 ml vial. Regardless of your supplier you can probably make bigger gains in cost savings by simply working to reinforce good technique amongst your staff.

It's hard to say what's happening from the information provided. You say that you are finding Ab's that the solidphase is missing when you repeat testing on the bench and that the reactions re weak at AHG phase. Your solid phase manufacturer claims that the Ab's are IgM. Since you use PEG you could be finding IgM antibodies that are weak as they do not have enough time to react at IS, then when you add PEG and incubate you do not read at 37 prior to washing and adding AHG. The reactions you see are possibly IgM that is weak and it has a broad enough thermal range to still be active at 37 and just needs enough incubation time to become evident. You didn't say what Ab's you are seeing or whether you have been able to make ID's on them. That information would be helpful.

IR thermometers can give you varying results depending upon where on the bag you aim them. The label can have a significant effect. IR passes through rbc's rather efficiently so aiming toward the edge where the thickness of the bag can also contribute to variability of readings. Your best bet is to validate temp readings to a region of the bag that gives you reliable results.

We notify the patient's attending if we dispense Rh Pos to an Rh neg patient, but only rarely does anyone decide to give RhIg. Apheresis platelets contain so few RBC's that this is not really a big issue with those products. Actually, with more emphasis on extracting the most volume out of whole blood for plasma I have seem far more bloody plasma units recently. We actually had a case of a 21YO female who received 6 units of Rh pos plasma along with 8 Rh Neg rbc's and subsequently developed an anti-D and C. The only explanation was RBC stroma contained in the plasma products for the D as she received no other exposure.

If I recall correctly they have at least one system in Europe. I believe it is in Switzerland. Sorry I can't be more specific. They do have CE mark, but previously lacked the sales & marketing muscle to do much outside the US. Perhaps now that Immucor owns them they will expand.

I used to work for them prior to their being bought by Immucor/Gamma. I might be able to answer some questions for you. The issue is how many instances of an antigen you feel that you need to identify. The system was pretty robust so getting a good result should not be the problem it is identifying the right strategy and collecting the appropriate samples for running the validation. Email me if you like.