Amra23

Thank you so much,Malcom!

Well, the high potassium is undoubtedly a factor, in particular as it is a cardiac case.
All units in the UK are leukodepleted, but I wouldn't have thought that "unleukodepleted" blood should be of too much concern in this case.
The difference in the Rh type would be of no concern to me whatsoever.  The baby's immune system would be immature, and so it is highly unlikely that the "foreign" Rh antigens would cause immunisation.  Indeed, exposure to these "foreign" Rh antigens may be advantageous in a way, as there is the possibility, as this age, that these may lead to "accomodation", meaning that the baby may never produce antibodies against these antigens, but this has not been proved, as far as I know.

Thank you,Malcom!I'm finally enlightened !

It is, nevertheless, true.  
Thorpe SJ, Boult CE, Stevenson FK, Scott ML, Sutherland J, Spellerberg MB, Natvig JB, Thompson KM.  Cold agglutinin activity is common among human monoclonal IgM Rh system antibodies using the V4-34 heavy chain variable gene segment.  Transfusion 1997; 37: 1111-1116.
Thorpe SJ, Ball C, Fox B, Thompson KM, Thorpe R, Bristow A.  Anti-D and anti-i activities are inseparable in V4-34-encoded monoclonal  anti-D: the same framework 1 residues are required for both activities.  Transfusion 2008; 48: 930-940.

I work in cardiac surgery unit.It is very simple for us.We have schedules with the patients every day and we know every case in particular.Every unit of blood is labeled with the pacient's ID,ABO/Rh group,crossmatch number,the name of lab worker who performed the crossmatch and also the date of the test.
We have 3 OR's and every time they need units of blood they call in our unit(which is only 2 floor distance) and we transport the units to them.They perform Bedside ABO/D test before every transfusion!All the dates from the blood unit are transcripted in patient's chart manually (we do not have a computer scan for that).
So far everything works great.
I am from east Europe country. 

I didn't know that! This is something I will always have to remember!

A few things as far as human reagents.
Firstly, you never know what else may be in them in terms of antibodies directed against low prevalence antigens, because there is absolutely no way that the producer has the ability to test for all such specificities (I can remember once a human-derived anti-D reagent produced at one of the places I worked, also had a Gm antibody in it that we didn't know about.  It is highly unlikely that this would have caused too many problems, but there is, nevertheless, a small chance that this could have caused a false positive).
Secondly, you never know what else may be in them in terms of viruses, some of which may, as yet, be unknown to us (remember, HIV, used not to be known).  This is a danger to the producer and the person using the reagent, rather than the patient.
Thirdly, the avidity of human reagents is, in general, pretty poor (particularly anti-D).
A few things concerning monoclonal reagents.
Some of them cross-react with other specificities (although not many), but, famously, monoclonal anti-D reagents will react with the I and i antigens if used straight from the fridge.
They have to be blended by experts to ensure that the desired epitopes are detected, but certain Partial D types (e.g. Partial D Type VI) are not detected (unless required).
They are very specific and very avid (both of which are greatly to be desired).
Virally, they are almost certainly sterile.
Hope that helps.

We do not have units in a fridge in OR (or anywhere else for that matter besides the BB).  Our BB is just down the hall from OR, so our OR units are kept in the BB until needed for a specific patient  Then they are issued in a cooler.  Presumably the correct ID and read-back is done in the OR for each unit.
Scott

I concur with the autoantibody conclusion. However, unless you've neglected to tell the forum important details about this case, this work-up should have stopped at a negative antibody screen (in cards).
I'm more concerned about why are you doing lots of extra work - especially an enzyme panel. And, why, oh, why are you using a "primitive", "insensitive" tube test when the super-sensitive card tests are negative /compatible?
If this is a "normal" work-up, I believe your testing algorithm needs attention.

My first thought is, how on Earth do you make sure your immediate spin saline tube technique at 37oC is strictly at 37oC (or have I got that wrong, and you are doing a saline tube technique at 37oC and an immediate spin at room temperature in addition; and, if so, were both incompatible?).
My second thought was, if the patient has not been transfused (as far as in known), you know his ABO, Rh and K type and the cross-match was compatible by IAT card technique, why did you perform the panels by IAT and enzyme card technique AND LISS IAT and, having found these negative too, why did you perform the other saline techniques?
I just do not understand.  It seems a huge amount of unnecessary work just to find a weak auto-antibody.

I agree entirely with exlimey, except to say that even today's monoclonal antibodies need a potentiator.  Many of them include a small amount of bovine albumin in the reagent bottle.
I don't, however, agree with you Jermin.
The reason being is that there is no such thing as a silly or daft question.  The only silly or daft question is the one you (anyone) don't ask, because, if that question is not asked. the person who doesn't know the answer will never know the answer.  Sadly, there are numerous examples of silly or daft answers!

The pacient will be programmed for a cardiac by-pass(miocardial ischemia);he has also diabetes type 2 and mixed dyslipedimia.Of course he is on medication for all theese.
We did not request the blood bank to perform tests for anti-Fya and anti-Fyb, and/or anti-Jka and anti-Jkb.