Is blood type O a panacea? Blood type O is not a universal blood

Blood type is a genetic marker in humans and is the type of antigen on the surface of a blood component. There are hundreds of blood group antigens in red blood cells, white blood cells, and platelets, and theoretically speaking, almost no two people have the same blood type except for identical twins. ABO and RH blood groups are the two blood group systems most closely related to human blood transfusion.

Blood type usually refers to the ABO blood group system of red blood cells, which is aimed at the different antigenic substances carried by red blood cells in the blood, and there are four blood types: A, B, O, and AB. The criterion and principle of classification is to see whether there are A and B antigens on the surface of red blood cells

Type A: only A antigen;

Type B: only B antigen;

Type AB: both A and B antigens;

Type O: neither A antigen nor B antigen;

We know that blood of different blood types cannot be transfused into each other, but blood type O can be transfused into people with blood types A, B, and AB, because blood type O has neither A antigen nor B antigen, and does not bind to anti-A and anti-B antibodies in these recipients, so that the transfused type O red blood cells are not destroyed. As a result, people with blood type O are often considered "universal blood donors".

Blood type O has its all-purpose side, however, whole blood type O is also a dangerous "universal blood". Since the plasma of type O blood contains anti-A and anti-B antibodies, if the amount of blood transfused into type O is relatively large, and the anti-A and anti-B titers in the transfused plasma are high, it will cause a transfusion reaction of immune hemolysis in the recipient. However, if the amount of blood transfused is small and the amount of blood in the recipient's body is large, the probability of immune hemolysis can be reduced through the effect of blood circulation dilution.

Blood type O is not a panacea!

Because there are no A and B antigens on group O red blood cells, type O washed red blood cells can be transfused to patients with types A, B, and AB when the primary side is matched. However, if the plasma containing anti-A and anti-B in the plasma of type O blood is transfused into patients with types A, B, and AB, it will cause different degrees of immuno-hemolytic transfusion adverse reactions.

The "Technical Specifications for Clinical Blood Transfusion" issued by the Ministry of Health clearly stipulates: "Red blood cell preparations containing type O plasma should be cross-matched before blood transfusion. "How can red blood cell preparations containing type O plasma be transfused when they are cross-matched with blood of type A, B, and AB?

In fact, if the recipient's blood contains irregular antibodies against other antigens of a bag of type O red blood cells, the bag of type O blood cannot be transfused into the recipient.

It can be seen that type O blood is not universal blood, and the outdated concept that type O is universal blood should be thoroughly updated, especially in some small hospitals that carry out blood transfusion, can not violate the provisions of the Ministry of Health's "Clinical Blood Transfusion Technical Specifications", and use type O blood to infuse patients with type A, B, and AB to avoid medical accidents, physical damage to patients, and reputational and economic losses to the unit.

There is no omnipotent in this world.

In an emergency, people who do not have type O blood can be transfused with type O blood.

Blood type O can be said to be a universal blood.

People with blood type O are universal blood donors, but unfortunately, people with blood type O can only receive blood type O.

I am studying medicine, and I remember that when the teacher talked about blood type, he said that people with blood type A can accept blood of blood types A and O, people with blood type B can accept blood of blood types B and O, and people with blood type AB can accept blood of blood types A, B, AB, and O (so people with blood type AB are universal blood recipients), while people with blood type O can only accept blood type O.

In addition to the four blood types A, B, O, and AB, there are also Rh blood types, and the matching principle mentioned above can only be transfused when Rh is also matched.

There are two types of Rh blood types: negative and positive, so with the addition of those four blood types, there should be eight blood types, such as negative for type A Rh and positive for type A Rh.

Therefore, ABO blood group and RH blood type should be checked during blood transfusion.

Most Chinese are rh-positive, while Europeans have many rh-negative.

Therefore, generally speaking, in China, when the Rh blood type is mostly positive, blood type O can be said to be a universal blood.

The ABO blood group system in humans is the first blood group system to be discovered, and it is the most important blood group system because of its regular blood group antibodies, which are divided into A, B, O and AB types. Among them, only type O people lack A and B antigens on their red blood cells, so when it is difficult to identify the ABO blood group of the recipient, the O type washed red blood cells that match the blood can be transfused; In addition, when there is insufficient or lack of blood of the same type at the critical moment of life-saving, a small amount of blood type O can also be transfused to relieve the urgent need.

However, type O plasma contains anti-A and anti-B antibodies, which can sensitize or agglutinate type A, B, and AB red blood cells, shorten their lifespan or destroy them immediately, and are contraindicated for blood transfusion. Therefore, type 0 whole blood was once called "dangerous universal blood". Some people ignore the word "dangerous" and refer to type O blood as "universal blood", which is wrong.

Because there is no A antigen or B antigen on the red blood cell membrane of type O blood, when giving blood to a patient, the red blood cell membrane of the donor does not have a deficiency of A antigen and B antigen, so it will not agglutinate with the antibodies in the recipient's serum, so in the past, type O blood was called universal blood. Side pants <>

Because there is no A antigen and no B antigen on the red blood cell membrane of type O blood, when giving a blood transfusion to the patient, the red blood cell membrane of the donor will not have an agglutination reaction with the antibodies in the recipient's serum because there is no A antigen and B antigen, so in the past, type O blood was called universal blood.

With the development of modern medicine, we know that clinical blood transfusion is based on the principle of blood of the same type, and blood type O is not a universal blood, and only in an emergency when there is no other blood type, can the patient be transfused with a small amount of blood type O slowly, in order to save the patient's life, if there is the same type of blood or the principle of blood transfusion of the same type. In the past, blood type AB was called a universal blood recipient, but in fact, AB blood type is not a universal blood recipient.

Blood transfusion has become an important means of improving diseases, saving the lives of the wounded and ensuring the smooth operation of the operation. However, it is not uncommon for patients to suffer serious damage or even death due to errors in blood transfusions.

Here, we focus on the ABO blood type. ABO blood group is a blood type that divides blood into 4 types based on the presence of proagglutina A and proagglutinum B on the red blood cell membrane. Where red blood cells contain only A agglutinum, it is called type A; If there is only a B-agglutination proto, it is called B-type; If both agglutinators A and B are present, it is called AB type; If these two agglutination originals are absent, it is called type O.

People with different blood types have different lectins in their serum, but they do not contain lectins that fight their own red blood cell agglutinin. Therefore, in the serum of type A people, only anti-B lectins are contained; The serum of type B people contains only anti-A lectins; There are no anti-A and anti-B lectins in the serum of people with type AB; In contrast, the serum of type O contains anti-A and anti-B lectins.

When preparing for a blood transfusion, we all know that the first step is to identify the blood type and ensure that the donor and recipient's ABO blood groups match, because incompatible transfusions of this system often cause severe reactions. For women of childbearing age and patients requiring repeated transfusions, it is also important to match the donor's Rh blood group to the recipient's blood group to avoid the recipient's anti-RH antibodies after sensitization.

Even if a blood transfusion is performed between people with the same blood type in the ABO system, a cross-match test must be performed before the transfusion, that is, not only the red blood cells of the donor and the serum of the recipient are tested for a seromating test (called the primary side of the test); In addition, the red blood cells of the recipient and the serum of the donor are tested in combination (called the secondary side of the test). In this way, it is possible to check whether the blood group is wrong, and to find out whether there are other lectinogens or lectins in their red blood cells or serum that can cause red blood cell agglutination reactions.

If there is no agglutination on either side of the cross-match test, the match is compatible and a blood transfusion can be performed; If there is an agglutination reaction on the main side, it is a blood match, and blood transfusion cannot be done; If there is no agglutination reaction on the primary side and an agglutination reaction on the secondary side, blood transfusion can only be carried out in an emergency situation, and the transfusion should not be too fast and too much, and closely observed, if a transfusion reaction occurs, the transfusion should be stopped immediately.

Some people say that people with type O are "universal blood donors" who believe that their blood can be transfused to any other person with ABO blood type. This argument is not advisable. Although the red blood cells of type O do not have A and B agglutinogens on them and are not agglutinated by the plasma of the recipient, the anti-A and anti-B lectins in the plasma of people with type O can agglutinate with the red blood cells of recipients of other blood types.

When the volume of blood transfused is large, the red blood cells of the recipient are widely agglutinated when the lectins in the donor's plasma are not sufficiently diluted by the recipient's plasma. In addition, there are also people with AB blood type who are called "universal blood recipients", which is also undesirable.

Blood transfusion is a multi-step process, and mistakes in each link can lead to serious accidents. Therefore, when performing blood transfusion operations, it is necessary to strictly abide by the principles of blood transfusion and pay close attention to observation; And blood transfusions should only be given when they are really needed, and they should never be misused blindly.

According to the immunological theory of blood group antigens and antibodies, blood type O cannot be transfused to people with type A, B, and AB. However, because there is neither a antigen nor B antigen on the red blood cells of type O blood, after transfusion to people with type A, B, and AB, type O red blood cells are not bound by the relative anti-A or anti-B antibodies in the serum of the recipient, so the transfused type O red blood cells are not destroyed, and play a good role in carrying oxygen and eliminating carbon dioxide. In general, we do not advocate transfusion of blood type O to people with other blood types, because the serum of blood type O contains anti-A and anti-B antibodies, and after transfusion into the body of people with other blood types, it can agglutinate with the red blood cells in the blood of the recipient and produce hemolysis.

Due to the small amount of blood transfused and the large amount of blood in the recipient's body, the hemolysis of bound red blood cells can be reduced through the dilution of blood circulation and the neutralization of some anti-A and anti-B antibodies in the blood group O serum by some blood group A or B substances present in the blood plasma of the recipient. However, if the amount of blood transfused is large and the concentration of anti-A and anti-B antibodies contained in the serum is very high, serious transfusion reactions can also occur, which shows that the "universal blood transfusion" is not a panacea, and it also has a serious potential danger. Based on the above, we believe that blood type O should not be transfused to people with other blood types except in special circumstances.

Adherence to homogeneous blood transfusion should be regarded as the most important basic principle in the field of blood transfusion.