Universal donor blood is sometimes not universally receivable due to Bombay phenotype and sub typings beyond the ABO/Rh bloodtypes such as P and Lewis etc. The bloodbank is still going to want to do a crossmatch even if there is O negative on the shelf. Yes, sometimes they are in too much of a hurry and might skip it now and then, but most of the time they will crossmatch.
I have worked in US trauma center blood banks ... they ALWAYS do the crossmatch, whether it's after the fact, or even post mortem, for any unit of blood that was partly or completely transfused. It is required by the AABB and if you don't follow AABB procedures, they shut your blood bank.
Here's the way AABB procedures work.
Screaming Emergency: The patient is going to die within a few minutes if they don't get volume, including RBC. ER/OR calls BB, lets them know how many units they need.
The doc signs a release for
n units of uncrossmatched blood, stating that the medical need for the blood is severe enough that the patient will not survive unless they get blood immediately. This absolves the lab of any responsibility beyond accurately handing over ONeg or type-compatible blood. "N" typically has an upper limit, to keep docs from tying up the entire supply of blood in their OR ... ours was 6 at a time, maximum.
Maximum number of uncrossmatched units I have personally handed over for one patient, over the period of under an hour, was 27 ... by that time she had no blood of her own left. We had cops using lights and sirens to bring ONeg from nearby hospitals.
Someone hand-carries that paper to the blood bank and waits for the blood. No signed paper, no blood for you.
In the brief time it takes for the paper to arrive, one BB tech has selected n units,snipped off a couple of the already labelled sample segments from the tubing on each unit, inserted them into test tubes, and started a "crossmatch sheet" for that patient and the blood they are getting. Until the emergency is over, no other tech touches that sheet or those segments ... if it's still screaming an hour before you are scheduled to leave, a second tech starts their own sheet and tracks "their" units and you finish the crossmatching and the paperwork for "your" units ... provided you have a sample from the patient. Techs cannot hand off an unfinished crossmatch - if they drop dead, the replacement tech has to start from scratch.
The blood bank labels and throws that number of ONeg units over the counter at the person with the request (actually, puts it into a labeled cooler with refrigerant). They also send someone
from the lab to tag the patient with the matching transfusion band (bright orange, can only be removed by cutting) and if at all possible, grab a few vials of blood to start screening, crossmatching, and shift to type-specific uncrossmatched if possible to preserve ONeg for the next trauma.
We're not worrying about the oddball blood types like Bombay or the possibility of a private antigen in these cases. These are the cases where blood is dripping off the gurney or OR table onto the floor.
Routine Emergency: In the absence of a release form, the blood bank does an immediate blood type for ABO and Rh so that type-compatible blood can be issued if a release form lands on them, starts screening the patient's blood for unusual antibodies using the "panel" (a commercial collection of human blood cells made from donors with convenient types that make it easy to spot the uncommon stuff that wrecks transfusions), and simultaneously crossmatching the requested number of units.
If the doc calls demanding blood before the crossmatches are completed, the blood bank tech reminds him that the only way blood leaves without a completed crossmatch is with a signed release form, would he like to sign for it or not? Usually not, because the release forms would always get reviewed by the chief of ER or OB/GYN or whatever.
A common emergency room order is "Type, screen and hold" ... meaning to get the patient's ABO and Rh, screen patient for antibodies to make sure there aren't any, and wait for further orders.
We had a set protocol for some emergencies: gunshot wounds to the torso or thigh automatically got a certain number of units set aside just in case they were needed, until the patient was out of surgery.
Impossible Transfusions: It has happened that a patient has an antibody that caused agglutination or hemolysis in every ABO and RH matched unit we tried, but was not identifiable with any of the cell panels we had.
When that happens, the blood bank will not issue any blood for transfusion, no matter what the doctors sign or threaten ... yes, they will die from blood loss, but killing them by transfusion reaction isn't any better. One idiot of a doc asked "
what if I just come down and take some ONeg" ... my reply was "
I'll testify at your homicide trial that I told you it would probably kill the patient and you transfused it anyway."
We would send samples off to the major antibody research centers, with all our results and the cell panels we used, screen blood relatives for potential donors, and hope we got lucky.
More often than not, the patient dies and their antibody is added to the long list of rare ones provoked by "private" antigens. Usually it's a woman with multiple pregancies, and her husband has the antigen. Less often it's someone who got multiple transfusions previously and we could check their earlier donors to see who had the antigen (for research purposes).
