Transfusion Reactions

Question: Why are ABO transfusion reactions so strong? I am in a medical technology program and I just recently started my immunohematology (blood banking) class. My first exam is in a couple days and I just had a question. Anti-A and Anti-B are mostly IgM antibodies and IgM are cold ab that react at a lower temp than body. So why are transfusion reactions(body temp) so strong?

Answer: when u perform antibody reactions in the lab u are working with a drop of blood. observe this under the microscope a nd u will see thousands of cells clotted. now imagine a whole bottle of blood ie a whole bottle of antibodies reacting with abt 5litres of blood present in the body. it causes the clumping of blood cells everywhere. the body is only 37C which allows these reactions to occur quite normally because the reactions are actually supposed to protect the body from foreign blood cells at body temperature. in the lab u use a cooler temperature so as not to denature the antibodies (proteins) and thus increasing the shelf life of the commercial antibodies.

Question: What are the signs and symptoms of blood transfusion reactions?

Answer: look up Google for answers

Question: Why are women who have given birth many times more prone to transfusion reactions?

Answer: Transifsion reactions is when your body recognizes something in the blood transfusion as foreign and creates antibodies against something in the blood, killing the new blood cells. This is more of a risk in woman who has been pregnant several times due to the Rhesus factor. Rhesus factor is an antigen (something an antibody can bind to) you either have or don't have (you are Rh+ or Rh-). If an Rh- mother has a baby that is Rh+, she might form antibodies against the Rh factor during pregnancy. So if she then is given a blood transfusion that is Rh+, her body will react to that and fend it off, even if it it is the right blood type.

Question: What is relevance of antigen-antibody reactions in blood transfusion?

Answer: Each blood type has different antigens. If the blood doesn't match or isn't compatible, then the body rejects the blood and attacks it in the same way as a pathogen. This is similar to organ transplants, if it isn't a match, the body will destroy it.

Question: how can we check blood transfusion reactions during blood transfusion?

Answer: How? By enlisting the cooperation of the patient. We can do this with informed consent. Transfusion therapy consent forms have the risks printed on them and having an awareness of these risks and having this verbalized as well before the transfusion is started is a big help. Having signs posted helps too. But we can do more than just this. We monitor our patients vital signs every 15 minutes for the first hour and then each hour (or according to facility policy). Knowing what to look for helps. Instructing your patient to report anything unusual helps, too. The patient can report chest pain, SOB, dyspnea, chills, fever, flank/back pain, rash, rapid heart beat and dizziness. We can assess for hypotension, hyperthermia, syncope, visible rash, flushing, tachycardia and hematuria. S/s usually appear during or immediately after but there can be a delayed reaction several days later and this is one of the things a patient is cautioned about. Of course if a reaction occurs during transfusion, the transfusion is D/C'd immediately and NS is run instead. That's why there's always a bag of it hanging along with blood. Hanging blood is a serious business and that's why we have all the protocols for it that we do from the ordering of the blood to post transfusion. Premeds (Benadryl and Tylenol) are given if patient has had a prior pruritic reaction (Benadryl) and to control the elevated temp that often happens (Tylenol) and if they've been ordered by the doctor.

Question: Explain why an Rh-negative person does not have a transfusion reaction on the first exposure? Explain why an Rh-negative person does not have a transfusion reaction on the first exposure to Rh-positive blood but does have a reaction on the second exposure. What happens when an ABO blood type is mismatched for the first time?

Answer: We have some imune cells in our body called Memory cells( like memory B cells and Tcells) when somebody is Rh+ it means he has the Rh antigene and when somebody is - means he don't. on the first transfusion when a blood with Rh antigene to a person that doesn't have this kind af antigene the imune system respond but in a mild way. it produces antibodies and this Abs attach to the surface of memory cells, but we dont have acute responce because the antibody rate in our blood is not very high. on the second transfution the cells react fast and strong and the symptoms appear! :) hope it is enough!

Question: Explain why Rh-negative person do not have a transfusion reaction on the first Rh-positive blood but? Explain why Rh-negative person do not have a transfusion reaction on the first Rh-positive blood but does have a reaction on the second exposure.?

Answer: You've got it backwards. A person with Rh positive blood will not have a reaction to an Rh negative transfusion of the correct blood type because there is nothing to react to; it's negative. The protein is not there. A person with Rh- blood will react to Rh+ simply because the + protein is present and will cause a reaction.

Question: Blood transfusion reactions? For example, Blood group O is considered a universal donor. Now, in a person whose blood type is O there is Anti-A and Anti-B agglutinins in their blood. If this person donates blood to someone, say of blood type AB as an example, won't the antibodies in the donor's blood agglutinate with the antigen on the RBCs of the recipient? Thanks in advance! Okay. I know that the person with AB blood group has no antibodies, what I mean is, when you are O group and you donate blood, you don't only give RBCs, you also give plasma, which contains the Anti-A and Anti-B. Now, won't these antibodies form complex with the recipient who is AB? or the donation is only red blood cells and plasma is excluded!? will you please explain

Answer: Excellent point. Here's how they get around that. Whole blood does contain all the red cells and plasma from a bag of blood donated. What they do now is squeeze out the plasma and only leave the red cells. This eliminates the plasma with it's anti-A and anti-B antibodies. The reason they do this is because stored plasma in the unit does not keep very well and doesn't have the valuable clotting factors as it ages on the shelf. It least that's the way it's done in most modern countries. If the entire whole blood were to be infused then there might be what they call a minor incompatibility issues. This occurs when the plasma of the donor reacts with the red cells of the recipient as you state. It is a relatively small volume of plasma. It is not as dangerous as when a blood unit of type A is infused into a type O patient. This would destroy the entire red cells and cause a major issue that can be life threatening. Each unit of blood can be separated into blood components and processed separately.The modern blood bank now has separate components transfused for use such as plasma that is frozen and then thawed for transfusion at time of use or platelets which are keep at room temperature.

Question: Why can plasma be administered to anyone without concern about a transfusion reaction?? The question is in reguards to blood transfusions.

Answer: Transfusion reactions are caused by proteins on the red blood cells, such as the A, B, and RhD proteins. Plasma has no red blood cells in it. Plasma is blood with the red blood cells removed.

Question: why does a person of type B blood go into transfusion reaction when given type B blood? i need po a broad answer that explains well....thanks! gBu

Answer: As the previous posters have pointed out, Rh incompatibility is certainly a potential reason for an ABO compatible transfusion reaction. The risk of a serious reaction following transfusion of ABO/Rh compatible blood is probably less than 1% -- but you asked for a broad answer... There are more than 12 other blood group systems aside from the ABO (A, B, AB, O) and Rh (Rh1, Rh2, Rh3 ... Rh5) systems. These include the Duffy, MNS, Kidd, Kell, P-system, and Colton blood group systems and others. I can't paste the link, but you can get to a really in-depth PPT presentation by entering "ppt abo and rh isoimmunisation" (with the quotes) in Google. A "type and screen" (T&S) a.k.a. "indirect Coombs test" involves mixing serum with red cells that have known surface antigens (to test for agglutination). To further ensure safety, a crossmatch (XM) can be performed prior to releasing blood from the blood bank to be transfused. In this test, a sample of the type-and-screened blood to be transfused is mixed with a serum sample from the prospective recipient to check for agglutination. There are other tests and even safer ways to prepare blood before it is transfused (e.g. removing white blood cells (leukoreduction)) and irradiation of blood, but these things are not routine (they are used in patients with bleeding disorders who have received (or are likely to require) repeated blood product transfusions throughout their illness (or for the rest of their life).