A plot point that frequently occurs in movies an TV shows is where someone requires a blood transfusion, but has a rare blood type and it’s hard to find a suitable donor. The show I’ve just watched (Dexter, season 1) the character had AB neg blood, and needed the same blood type for a transfusion. I’ve seen the same thing in a few other movies and shows.
Is this cliche accurate? I thought that AB is “the universal recipient” i.e. it can accept a transfusion from type A, type B, type AB, or type O. I thought it only mattered if someone receives a transfusion with a factor that the recipient doesn’t have, for instance if a type O patient receives a type B transfusion it could kill him, but the other way around is safe.
Is this correct? Or am I wrong, and TV right?
According to TV Tropes, at least, you’re on the right track. As far as I know, virtually anyone can receive O- blood safely.
I am O-negative and almost anyone is golden for a blood transfusion as long as I am around.
Neither of those answers is the whole story; the reality is that ideally every unit of blood is thoroughly tested for compatibility by cross-match before being given to a recipient (I’ve spent my time doing stat cross-matches as people are bleeding in the ER). There are other blood types than ABO and Rh, and you want to avoid a transfusion reaction if possible.
You won’t get results that are too bad from giving an AB patient A, B, or O, but it’s best to match the blood type exactly. There are detrimental interactions from giving an AB patient A blood, for example, they’re just relatively minor.
Now, in an emergency situation, it’s often more important to get the blood quickly (without having to wait for tests) than it is to get exactly the right type, which is why O negative is in such high demand. But if you’re prepping someone for surgery, or the urgency is on a scale of days or weeks rather than minutes, then you want to get it right.
That said, anything in the ABO system can’t really be considered a “rare blood type”, and the hospital should have some already in stock. There are, however, some truly rare blood types that can’t be described in terms of ABO, and if the patient needs one of those, they would have a hard time finding a donor.
A good chart for the ABO type matching is here.
Blood banker here. Matching ABO groups should be no problem for any hospital that has a transfusion service. If ever in doubt, O- are the ones to give. Problems arise from antibodies.
A brief primer on transfusion medicine:
Blood cells have antigens on their surface. The most commonly known by laymen are the ABO and Rh antigens. For illustrative purposes, you can imagine that a group A person has a bunch of microscopic 'A’s sticking out of the surface of their blood cells. Group B people have ‘B’ antigens sticking out of their cells, group AB have both ‘A’ and ‘B’ antigens and group O people lack both A or B antigens. Rh antigens are actually combinations of D, C, c E and e antigens. There are many other blood group antigens that can be used to group blood (ie. Kell, Duffy, Lewis MNSs, I, Lutheran, Kidd…etc, etc). Everyone has a unique pattern of antigens on their blood that your body learns as ‘self’ and everything is fine.
Once you introduce someone else’s blood into a person, you run the risk of creating problems. This is because no one person’s antigen profile is exactly the same as anothers’. So, if you give Frank some of Tommy’s blood, Frank’s immune system may realize, ‘hey! I’ve never seen this antigen (x) before! MOUNT THE DEFENSES!’ Now Frank’s body will create an antibody to x (anti-x). Because this is a first exposure, it takes awhile for antibody production to ramp up, so the x cells will be slowly removed over the course of a few weeks. No problem. The problem now is if a SECOND exposure happens. Frank’s body is now primed to recognize antigen x. There is anti-x in his blood and a second exposure results in immediate hemolysis or even clotting which is very bad and may be fatal. Now imagine if Frank has some condition whereby he needs blood every couple of weeks. He’s been exposed to hundreds of different people’s blood and may have 2 or 3 or 4 antibodies. The transfusion services’ job is now to screen random blood units that have an antigen profile lacking those 2 or 3 or 4 antigens. This is very difficult as it involves testing a shitload of units until you find one or two or ten or twenty that are acceptable.
Now, let’s say Frank has some kind of accident where he needs a blood transfusion immediately. The blood service at the hosptial will detect that he has antibodies. It takes time to identify the antibody (more time if there are more antibodies). Then it takes even more time to find compatible units. Frank may be dead because we can’t find compatible blood in time. This is the only example of ‘hard-to-match’ blood. (Besides weird genetic anomalies that result in crazy blood, but these are rare as hell).
Just to clarify a point: for the A or B antigens, the opposite antibody is almost always present (there are exceptions, but those are zebras). So, a type A person will have B antibodies, a type B person will have A antibodies, a type AB person will have no antibodies and a type O person will have both A and B antibodies (cf. Lansteiner’s Rule). ABO compatibility means having to match the antibodies in the recipient’s blood to the antigens present on the donor’s red cells. Antibodies are present in the serum, or liquid portion of blood, not with the red cells, which are what are transfused. The other antigens mentioned (the Rh family, Kell, Duffy, S, s, etc.) appear in varying percentages of racial populations, and those antibodies are not normally present, unless the patient has been previously exposed, as Nunavut Boy explains.
I miss blood bank, particularly nailing down an unexpected antibody. Chasing down positive DATs were a pain in the neck, though because they were often unidentifiable.