bmarotto

The notification was about the prediluted 0.8% cells. One of the recommended options was manually diluting 3% cells with Diluent 2 which does not have the propylene glycol preservative. We decided to continue using the 0.8% cells with 15 minute incubation. If a screen is positive and the panel is inconclusive but shows weak reactions with any K or E pos cells, we may investigate further with PeG and/or diluted 3%cells. I have seen no data on the clinical significance of the "missed" antibodies. Those who have been around long enough will remember that enzymes detected Rh antibodies that were not detected by the routine methods in use at the time. These "enzyme only" antibodies were unlikely to be implicated in hemolytic reactions and most blood banks did not incorporate enzyme testing into their antibody screen procedures. We have known for years that no method will detect every antibody. I can't see adding 15-25 minutes to turnaround time to possibly detect a weak anti-K or anti-E of uncertain significance. Another thing to consider: would routinely incubating 40 minutes cause the detection of more nuisance antibodies? If studies show these antibodies to be clinically significant, then we will reconsider our position.

The problem is with the electronic crossmatch feature, which is a new option in GUI Blood Bank. Rh positive units can be issued as long as a serological crossmatch is done. Misys acknowledges this is how the program was designed to work, i.e. to block electronic crossmatching anytime there is any kind of QA failure. It is not just limited to the Rh pos blood to Rh neg recipient scenario. My issue is that it sometimes blocks electronic crossmatching on qualifying patients for reasons other than ABO incompatability.

My hospital lab has been a Misys (formerly Sunquest) site since the mid 1980's (Blood Bank went live in 1990). We worked out a way to do electronic crossmatching and received FDA approval in 1995. Misys now offers an Electronic Crossmatch option and I was excited to test it out. After playing with it in our test area, I am concerned that it is overly restrictive. Any QA failure, even if legitimately overridden, will block units from being electronically crossmatched. For example, if it becomes necessary to switch an Rh negative patient to Rh positive blood due to massive transfusion, units can not be electronically crossmatched even though the patient has the required two blood types and negative antibody screen/history. My understanding of the electronic crossmatch is that it is used to determine ABO incompatibility when a patient has a negative antibody screen & history. True, the system must alert the user if there is a patient/donor Rh discrepancy but should it BLOCK the electronic crossmatch? It also blocks electronic XM if a patient requires irradiated blood and the units are not irradiated. It will, however, allow these units to be serologically crossmatched. Where is the logic here? It is the Rh pos unit to Rh neg recipient scenario that poses the biggest problem. Often, this occurs when massive units of blood are needed emergently. Going back to tube immediate spin xm in these cases is going to cause a delay in getting blood to the patient. Does anyone know how/if other software vendors are handling electronic crossmatching?

I see no reason to routinely perform DATs on donor units. If you get an incompatible XM at AHG that does not make sense with your antibody screen or antibody ID result, then you can do a DAT on the unit to see if that is causing a false positive. For example: 1. Patient has a negative antibody screen but one unit is incompatible at AHG. Do DAT to differentiate false pos from possible antibody to low frequency antigen. 2. Patient has anti-E and a unit that was typed E negative is incompatible at AHG. Do DAT to help diffentiate false pos from possible additional antibody to low frequency antigen or incorrect E typing on unit. We have it written into our SOP that these are circumstances when performing a DAT on the donor unit is indicated. Good luck....I think you are trying to move in the right direction.

Kate, We just ordered the STS Quality Advantage software to help us validate Misys v6.1. I am hoping to have it installed sometime in the next month. So I can't answer any of your questions yet. Once we have it up and running, you are welcome to come check it out. Bev

Thanks everyone. We now have three patients who have received dump freeze products. Engraftment has been right on schedule for each of them.

We were able to get a double collection on our last patient and we infused the "dump" frozen product. Engraftment was right on schedule for both WBC, granulocytes, and platelets. We did add a second patient to this phase of the validation. Infusion is scheduled for next week. We are keeping our fingers crossed.

My hospital blood bank supports our small autologous-only peripheral blood stem cell program. My techs do both the collection (15-25 liters processed) and cryopreservation. The entire process runs into 2nd shift and involves calling in techs if a procedure has to be done on a weekend. In an attempt to reduce tech time, I would like to switch from control-rate freezing (CRF) to dump freezing. The product would be put in -80 immediately after processing and then moved to LN2 vapor storage the next day. For validation, I have multiple references comparing the two methods showing similar engraftment. I have also monitored the dump freeze cooling rate. I thawed product scheduled for discard and refroze them by the dump method, recording the product temperature at one minute intervals. I used the same sample probe used to record product temperature during CRF. I made adjustments on how the canisters were placed/insulated in the -80 until I found an arrangement that consistenly yielded an average cooling rate in the 1.00-1.75 degree/minute range until a temperature of -60 degrees was reached. I also compared the sample warm-up during the heat of fusion phase from several CRF tracings and found them to be comparable to what I recorded during the dump freeze procedures. I would appreciate any comments on the adequacy of this validation. Our program director suggested doing a double collection on our next patient and freeze half by CRF and half by dump method. He would then infuse the dump freeze cells, keeping the CRF cells in reserve should there be a problem. We would also check post thaw viability for each method.

The Blood Bank uses a blood warmer on the return line when performing plasma exchange and peripheral blood HPC collection. We also issue a warmer to nursing units for patients with cold autoantibodies reactive at 37 degrees. The O.R., SICU, and trauma have the same warmers which they use for rapid fluid and blood infusion. Biomedical department performs temperature and alarm checks on all warmers quarterly. For apheresis procedures, we record the temperature display every 30 minutes when we record the run parameters. For transfusions on the floor, we send a sheet for nursing to record the temperature display during the transfusion and return to the Blood Bank. Is this necessary? O.R., SICU, and trauma are not recording the display temperature when they transfuse blood through a warmer, but they do indicate that a warmer was used.

We also have the IBL437C but without a PC attached. We QC the IBL timer daily so I guess that is all we can do.

TRM.44984 asks: Is there a maintenance schedule for all blood irradiation equipment including timer checks, back-up timer checks, turntable inspection, and radiation leakage testing and does documentation show that the maintenance is performed? Can anyone tell me what is meant by "back up timer checks"?

We also limit the use of the microscope to DAT and rouleaux. Our other use of the microscope is to aid in determining if a weak reaction is mixed field. Many techs are not comfortable differentiating between a weak mixed field and a weak reaction based on macroscopic viewing alone.

Mario, are you aware that MiSys was NOT planning on interfacing with the Digitrax ISBT label printing software? I submitted it as an enhancement request and it was discussed during the May 25th Blood Bank SIG call. It was rated a 1 (critical risk). MiSys has a discussion with DigiTrax planned this coming week. You may want to contact your MiSys support person to voice your opinion and get the latest information.

Same at my facility and yes, from waht I hear it does mean we have to barcode the unit number and our facility ID.

What department at your hospital manages each of these products? 1. Albumin 2. Clotting Factor concentrates 3. Rh Immune Globulin-intramusular 4. Rh Immube Globulin-intravenous (WinRho) 5. IVIg