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LeeHL, Have you made Wright Giemsa smears?

KKidd, I have found a useful tool in the histogram itself for guaging percentages of antigen negative cells. Depending on the donor population of the panel cells and how it compares demographically to red cell donors of a particular geography one can get at least a ball park estimation.

Sheryl, I have experienced the lable being off print such that the bar code is too close to one end or the other. I just attach a piece of white lable to increase the amount of blank space at the short end so the bar code reader can distinguish the ends.

BankerGirl, Were the Panel Cells approaching their expiration date as well? If not when do they expire in comparison to the screening cells. And for the other posters; how does the anomaly antibody explain post #8 of this thread, the 4+ mixed field reactions, and the absolute lack of reactivity in any of the panel cells? I would be more confident in this theory if the reactivity were no greater then 2+ and if we saw any reactivity in the panel cells; or given that the screening cells were 4+ mixfield and any equal reactivity in the panel cells.

BankerGirl, It is possible that the original plasma tested with the screening cells was contaminated with platelets and or white cells. Since we add the screening cells first to the columb followed by the plasma, platelet and or WBC's would migrate to the surface of the gel after a population of the screening cells had a chance to migrate into the gel. Thus after testing is completed the cells that were able to migrate into the gel prior to the platelet and/or WBC sealing off the surface of the gel would be at the bottom of the colomb and the rest would be sequestered at the top producing a 4+ mixed feild reaction. The plasma tested twenty four hours later would be platelet and/or WBC poor and therefore produce negative results. This senario would have also potentially occured with fibrin stands as well. Still, the burning question is why didn't we see similar results in at least one of the panel cells tested? A likley possibility is that there was indeed a plasma contaminant, ie platelets, WBC's, of fibrin strands, such that one or more were present in the reaction volume of the antibody screening tests and approximately 30 minutes later when the testing was complete, the contaminant settled out enough so that it would not be present in the reaction volume of the panel cells. Given the information provided this is a very likely cause. I hope this helps a little bit. :)

Malcolm, do they not use the same antibiotics in the panel cells? If so, why was the panel negative? These are very strong reactions and I would suspect fibrin formation in the plasma but I would have also expected similar reactions with the panel cells. Non-the-less, did you try respinning the patient specimen and repeating the screen? Did you get a diagnostic history on the patient including current medications? Also, and not to leave a stone unturned, did you check the expiration date and viability of your screening cells? Furthermore, would you consider repeating the Ab screen using a different in-dated set of screening cells?

Mable, When I read your post it reminds me of an article I read in Transfusion Mag. some time ago where the US Army did a study of the use of FFP for initial treatment of battle field trauma and showed a better prognosis for patients who recieved FFP first as opposed to recieveing PRBC's first. Given how remote your facility is I wonder what your use of FFP is for trauma patients and if the practice mentioned might be better for your patient given your limitted RBC inventory.

Malcolm, Thank you for the response, but I'm not sure of how you arrive at your stated conclusion; and if there were this reactivity isn't that important info in determining if there is an IgG bound Ab and what specificity it has. The fact that the Auto Control and DAT are both positive would point to a bound IgG Ab and of course the eluate would lend to understanding it's specificity; But again, how do you arrive at an Rh Ab?

John, How old is the PEG in use; when was it opened? Do you use PEG regularly?

Mary, Why take a chance? Do the Ab screen when performing the type.

It has been a while since I have taken statistics but I do remember that there is a minimal number of samples, or data, needed to satisfy the "P" value, which confirms that the data being generated is do to specific reactivity, as opposed to the knoll hypothesis, which suggests that the aquired data are do to randomly occuring events and no specificity.

Brenda, I agree that the use of a second specimen drawn at a different time is most sensible in assuring a patient's ABO/Rh type that has no prior history at the facility; I have heard many cases of how the arm bands are removed for IV's both in the patient's room and the OR; especially the OR, there the docs will remove the arm bands in a heart beat if they are in the way, and there goes your ID. I had stated earlier that I have practiced using a second specimen from a previous draw that may not have been for BB testing at all.

kriti, I'm just curious, but what floor, and /or where in the building is your blood bank located??

Hey Mable, Are there any other hospitals closer than 3 hours away that may be able to transport blood products in an emergency?

msdesoki, Once the DAT testing shows a positive result an elution is the next logical step in identifying bound antibody.

Martha, We require a second typing be performed on a patient with no history but we can use an other specimen from a different collection time instead of drawing a second specimen if possible. This may work better for your night shift staff.

BarbaraKym, How are you resulting a Du Pos baby that is DAT Neg?

dhil, My question to you is how do you determine if the patient has been "stimulated" within the last 3 months. Do you check history at your facility? Do you check history at nearby facilities? Do you check history at facilities throughout your state, throughout other states, throughout the country, outside of the country, etc..? I apologize for being cynical but my point is that we only have the ability to check patient history usually within our own facility and so it is better to error on the side of caution and abide by checking the specimen every three days which is apparently the minimal number of days where we might detect the product of a sensitization event.

You are absolutely correct in that the titer of allo D would be but one peice of an overall set of data.

The only thing that concerns me about the practice of IS Rh-Neg; which in of itself is not a bad practice; however I have observed the practice of administering RhoGam without performing the ABSC. I would think that this practice would complicate our ability to titer an allo D, if it were demonstrated, and therefore obstruct the physician's ability to judge the need for interuterine transfusion.

Can you explain what "Passenger Lymphocyte Syndrome" is??

Are there any known cases where D neg platelets caused allo-D antibody formation? Given the info in the previous post by jeanne.wall, in 1998 they seemed sure of the practice and in 2009 they seem to question it. I wonder why the change in opinion after nine years?

Suhu, when you use the term "swirl" here do you mean that we are not seeing visible platelet agglutinates in the platelet product? I am not familiar with the use of this term here.

We require ABO/Rh confirmation and a DAT on pre and post reaction specimens along with a post Urine speciman, in addition to the clerical check for the initial investigation.

Suhu, Sorry for the late reply, but normally we do not have a patient name for a trauma so we write the unique trauma patient number and the associated medical record number on the unit tag. We do pretag O Pos PC's containing all pertanent info except the the two unique patient indentifiers. We will opt for ABO Rh specific PC's when practicle, otherwise O Pos PC's are the red cell product of choice. I hope this helps and again I apologize for the late reply.:) To answer Mary's question, our unit tags contain graphics for vital signs which the nurse fills in accordingly. Also, I would like to ask what are the turn-around times practiced for Massive Transfusion products at other facilities, mainly PC's??; at my facility it is 15min for PC's.