Blood group

Blood group - normal inherited various immunological characteristics of blood. On the basis of these signs all people are divided into four groups, regardless of race, age and sex. Blood group a person remains constant throughout his life. People of one blood groups are different from people of other blood groups, the presence or absence of agglutinogenic (a and b), as contained in red blood cells, and agglutinins ascension and?, are contained in the serum.
Blood group system AB0 : 0(I) blood group contains agglutinin ascension and?, agglutinogen no; And (II) the blood - agglutinin ascension and agglutinogen And; (III) blood group-agglutinin and agglutinogen In; AB(IV) blood group - contains agglutinogen a and b, agglutinin missing.
The recipient is the person who receives the blood, the donor - the person giving his blood for transfusion. Ideally compatible with recipient is the blood of the same group. The blood is totally incompatible, if a recipient has agglutinin to the red blood cells of the donor, as in these cases, connect agglutinogen And one blood with agglutinin and another or agglutinogen In with agglutinin?. Develops the so-called agglutination, i.e. the agglutination of red blood cells in small and big lumps. Transfusion of blood incompatible leads to serious consequences and may cause death. Recipient 0(I) the group should not be transfused blood is no other group, except the same. The recipient AB(IV) group no agglutinins no, so he can pour the blood of all groups. The recipient AB(IV) group - universal recipient. Blood 0(I) the group can be provided to people with any blood type. Therefore, people with 0(I) by a group called universal donors.
In addition agglutinogenic and in erythrocytes meet sometimes other agglutinogen (for example, rhesus factor and others). In those cases, when the blood incompatible in rhesus factor (see), to produce transfusion also cannot avoid the serious complications associated with the destruction of red blood cells (hemolysis).
Before each blood transfusion, conducted for the purposes and under the supervision of a physician, you need to have the blood group and identify its compatibility.definition blood group
Fig. 1-4. Determination of blood groups with standard sera (a, b, 0). Fig. 1. Test blood group 0(I). Fig. 2. Test blood group a (II). Fig. 3. Test blood group b (III). Fig. 4. Test blood group AB (IV).
The method of determination of blood groups. To determine blood group prepare a clean plate, pencil for glass, standard serum 0(I), (II) and(III) blood groups, bottles with izotoniceski solution of sodium chloride, alcohol and iodine, absorbent cotton, subject glass or glass sticks and three pipettes, which must be dry (water destroys red blood cells).
The plate share pencil on three sectors, which indicate 0(I)And(I)To(III). On a sector different pipettes put on one of the large drop of the standard serum 0(I)And(II), (III) blood groups. After pipette released a drop of serum, it is immediately put into the bottle, from which it was taken. Finger before taking a blood alcohol wipe. After the injection in the flesh of your finger with a needle squeeze a drop of blood. Glass rod or corner of the net slides carry three drops of blood (each the size of a pinhead) on a plate next to the sera 0(I), (II) and(III) blood groups. Noting the clock time, every time a new glass sticks mixed blood alternately with sera for blood group 0(I), (II) and(III)until the mixture becomes evenly pink. Definition of blood group produce over 5 minutes (to watch by the clock). After this time each drop mix add one drop izotoniceski solution of sodium chloride. Then the plate of blood shake slightly, moving in different directions so that the mixture is well mixed with izotoniceski solution of sodium chloride, but not spread inside the glass. In case of positive reaction within the first minutes of starting the mixing before adding isotonic solution in a mixture appear tiny red grains, consisting of sleepsense erythrocytes. Small grains merge into larger, and sometimes in the flakes of different sizes (the phenomenon of agglutination). When negative reaction mixture is evenly painted in pink. The test with three listed above sera for each group of blood can drop a combination of positive and negative reactions (Fig. 1-4). If all three of serum gave a negative response, i.e. all of the mixture remained evenly painted in pink, tested the blood belongs to 0(I) group. If negative reaction gave only serum And(I) group of blood, and serum 0(I) and(III) blood tested positive, that is, they appeared grain, tested the blood belongs to a(II) group. If the serum In(III) blood group gave a negative reaction, and serum 0(I) and(II) group of blood - positive, then tested the blood refers to In(III) group. If all three of serum gave a positive reaction, i.e. everywhere appeared grainy, tested the blood refers to AB(IV) group. Any other combination indicate an error in the definition. Sources of error in the determination of blood groups and measures of their prevention. 1. The excess of blood, if taken too big drop. A drop of blood must be 10 times less than a drop of serum. 2. If serum weak or erythrocytes Respondent's bad stick together, you can view the agglutination (see), as the reaction starts too late or is poorly expressed. You should take reliable serum, which activity is tested and the expiry date has not passed. 3. At low ambient temperatures may come nonspecific cold agglutination - Panagyurishte. The addition of an isotonic solution of sodium chloride with the subsequent swinging plates usually destroys cold agglutination. To avoid this, the ambient temperature should be no lower than 12 and not more 25oC. 4. During a long observation mixture begins to drain from the periphery, where sometimes there is a grain. In the absence of grain in the liquid part of the mixture it is possible to speak about negative agglutination reaction.
Once the blood, the physician should immediately make a record on the face sheet of the history of the disease. After work the plate, pipettes and the glass should be cleaned thoroughly under running water with warm water, wipe dry and put in the wardrobe. Serum in ampoules or bottles are stored in a dry and warm room in a locked cupboard at temperature not above 20 deg.
Definition of blood group by standard red blood cells (so-called double reaction) apply only in laboratories and stations of blood transfusion. In everyday work are agglutination reaction with standard serum by the method described above.