Tip 1: What are the differences between human blood groups

Medicine

Tip 1: What are the differences between human blood groups

The blood of different people varies in composition, in totalIsolate four blood groups that have different chemical elements in plasma and red blood cells. Such differences are caused by evolutionary changes, earlier all people had one, the first blood group.

Composition of blood

The ancient people, according to the scientists, wereone group of blood - the first. Gradually, the evolution of man to the changing conditions of the environment and his own way of life led to the appearance of other variants of blood. Today, there are four blood groups that differ in composition. The blood consists of a fluid called a plasma. It basically consists of water, but it has a number of dissolved substances that play a big role in the functioning of human organs - antigens that are scientifically called agglutinogens. The plasma contains special cells - erythrocytes or red cells that do not have a nucleus: agglutinogens are on their surface. The internal chemical composition of these cells varies from person to person: certain antibodies or agglutinins may be present. The contents of all these substances both in plasma and in erythrocytes differ in blood groups. Thus, in the first group, agglutinogens are not contained in the plasma, and in the erythrocytes there are agglutinins α and β. The second group is characterized by the presence of agglutinogen A in the plasma, and agglutinin β in the red cells. A person with a third blood group has antigen B and antibodies α. The fourth blood group contains agglutinogens A and B, and in erythrocytes there are no agglutinins. Thus, in the first place, blood groups differ in composition, but such differences cause in the human body more serious changes. Depending on the blood group, a tendency to certain diseases is developed: for example, the first group speaks of a predisposition to stomach diseases, and the second one - to heart diseases. The blood group of a person is determined by inheritance: for example, parents with a fourth group can not have a child with the first.

Blood transfusion

Differences in blood composition have made it impossibleunhindered to transfuse the blood of one person to another, since the mismatch of their groups can cause conflict. So, a person with the first blood group is considered a universal donor - his blood is suitable for all people. The second group is suitable only for the second and fourth, the third - the third and the fourth. And the blood of the fourth group can be transfused only to owners of the same type. But such people are universal recipients, they take blood with any composition. The least fortunate was the owners of the first group - they can only receive the same blood. And people with the second and third groups are suitable either the same type as they have, or the first.

Tip 2: How to Transfuse the Blood

Transfusions are performed by transfusiologists insterile conditions and strict indications. Before the procedure, samples are taken to determine the blood groups and Rh factor, the compatibility of the donor and recipient blood.

You will need

- a bottle with donor blood;
- system for transfusions;
- a tripod;
- a set of standard sera for determining blood groups;
- white porcelain plate for determining blood groups;
- polyglucin solution;
- saline;
- test tube;
- slides;
- scarifier;
- cotton balls;
- solution of alcohol.
- pipettes.

Instructions

Determine the recipient's blood group by the ABO system and the Rh factor.

Assess the blood supply of the donor for transfusion. To do this, check the passport of the vial, the integrity of the package, the expiration date, compliance with the storage regime, the appearance of the blood.

If blood donor is suitable for transfusion, determine its group by the ABO system.

If the blood groups and the Rh factor of the donor andrecipient coincide, test for individual compatibility of donor and recipient blood in the ABO system. To do this, mix 0.1 ml of the recipient's blood serum and 0.01 ml of donor blood from the vial on the glass. If blood compatible with the ABO system, there should be no agglutination.

Run a test for individual compatibilityby the Rh factor. To do this, drop 2 drops of the recipient's serum into the tube, 1 drop of donor blood, 1 drop of polyglucin. Rotate the tube. Then add 5 ml of saline. The sample is evaluated in the same way as in the previous paragraph.

If blood is compatible with the Rh factor, assemble a system for blood transfusion and connect the system to the vein without opening the roller clamp.

Carry out a biological test. To do this, open the clamp and inject 20-25 ml of blood. Close the clamp and observe the recipient's condition for 3 minutes. If his condition has not changed, repeat the injection of blood by the same procedure 2 more times. If after 3 administration the patient feels satisfactory, enter the entire remaining volume of blood at a rate of 40-60 drops per minute.

During the transfusion, measure the blood pressure, heart rate and temperature of the patient. If the recipient feels unwell, immediately stop the transfusion.

Close the clamp and disconnect the system from the recipient's vein when 10-15 ml of blood remain in the vial. The vial with the remains of blood should be placed in the refrigerator.

Complete the documentation.

Tip 3: What kind of blood can be given to all groups

Currently, people are poured blood strictlythe same group as their own. This necessarily takes into account Rh-accessory. Such concepts as a "universal donor", whose blood is suitable for any group, and the "universal recipe", to whom the blood of any group fits, are obsolete. According to today's ideas, there is no "universal" blood.

Instructions

At the very beginning of the twentieth century, an Austrian scientistKarl Landsteiner made an outstanding scientific discovery. He took samples of blood from himself and five colleagues. Then he alternately mixed the samples. Analyzing together with L. Yanskii results on agglutination (formation of clots), revealed three blood groups: A, B and O. Soon his pupils A. Shturly and A. Dekastello discovered another, fourth group - AB.

The overwhelming majority of the population are carriersblood groups A, B, AB and O. The blood group of a person depends on the presence or absence of certain substances on the surface of red blood cells - erythrocytes, blood components responsible for the transfer of oxygen throughout the body. These substances, consisting mainly of proteins and carbohydrates, are called antigens. In addition to antigens A and B, more than 600 antigens are now known.

The human body produces antibodies toantigens not present on their own erythrocytes. The organism recognizes these antigens as alien. For example, people with blood type O develop anti-A and anti-B bodies, since they do not have antigen data on their red blood cells. When a patient needs a blood transfusion to prevent a potentially life-threatening reaction, the blood obtained should not interact with these antibodies. Thus, a patient with anti-B bodies can not be transfused with blood of groups B and AB, since red blood cells carry antigen B. To a person with a rare blood group, it is sometimes as difficult to pick up a donor as to find a needle in a haystack.

The antigen D, or, in another way, Rh, is calledRh factor. People with a positive Rh factor can receive both Rh-positive and Rh-negative blood. People with a negative Rh factor do not have D antigen. In most cases, the same Rh-negative blood is poured. However, if a person with a negative Rh factor has not yet developed antibodies to antigen D, he, in exceptional cases, can transfer Rh-positive blood. As soon as a person with a negative Rh factor receives Rh positive blood, his body will start producing antibodies to D antigen and a repeated transfusion of Rh-positive blood will become impossible.

According to the ideas of the mid-twentieth century, peoplewith the blood group O and the negative Rh-factor were considered "universal donors". Such blood could pour any needy. The incompatibility of the "first negative" with other groups was observed infrequently, and this circumstance was ignored for a long time. Now such a transfusion is permissible only in desperate situations and in a volume of not more than 500 ml.