anticoagulants, blood groups presentation.pptx

Anticoagulants are medications that prevent or reduce the formation of blood clots.

1. Anticoagulant and B lood groups DR JAWED IQBAL BAJEER MBBS, M.Phil

2. Anticoagulants A substance that decrease or prevents the clotting and prolong clotting time Commonly known as blood thinner Anticoagulant medicine that help prevent blood clots given to people which are at high risk of developing clots such as stroke and heart attack

3. Heparin Natural anticoagulant , given parentarlly Increase activity of antithrombin III Binds with antithrombin 111 and exposes its active site Antithrombin 111 binds with thrombin & factors 9,10,11 and 12 and inactivate them It inhibit the intrinsic &common pathway of clotting cascade

4. Warfarin Synthetic anticoagulants , given orally These act as vitamins K antagonists Inhibit the gamma carboxylation of vit K dependent clotting factors prothrombin , factor 7,9,10 and protein C & S so these factors are not activated Inhibit extrinsic & common pathway of clotting

5. Prevention of clotting outside the body Blood normally clots in about 6min in test tube Chemicals (prevent clotting out side) Soluble oxalates : cause precipitation of ca + in blood in the form of ca + oxalate that decrease ca + level Citrates : combine with ca + to form unionized ca + compound, so lac of ca + ions prevent clotting

6. Blood Groups These are glycoprotein antigen present at the surface of RBC Also called agglutinogen Antibodies against these antigens present in the plasma Also called agglutinins

7. ABO system Antigens: A person have A, B,AB both or no antigen Antibodies : Group A has antibody B Group B has antibody A Group AB has no antibodies Group O has both antibodies A,B

8. Land steiner law If an antigen present on the RBC , then corresponding antibodies must be absent from the plasma Antibodies develop as a response to substances chemically similar to human blood group antigen

9. Rh system Second important blood group system is Rh system Antigens : there are 6 types of Rh antigens C,D,E,c,d,e D antigen is dominant antigen Person having D antigen called Rh+ve Persons without D antigen called Rh- ve

10. Antibodies : Rh antibodies are not present in the plasma Produced by two ways Transfusion of Rh + ve blood to Rh- ve Presence of Rh + ve fetus in Rh – ve mother

11. Cross matching Cross matching is must before transfusion Rh + ve should not be given to any Rh- ve female because she will sensitized and form anti Rh antibodies and these can cause dangerous to Rh + ve fetus when she become pregnant Agglutinogens of donor are matched with agglutinins of recipient

12. Universal recipients : Person of blood group AB + ve contain all antigens, so they can receive from any group Universal donors : Person with blood group O- ve do not contain any antigen , so they can donate at any groups

13. Hazards of blood transfusion Hemolytic transfusion reaction Tetany Anaphylactic shock Febrile transfusion reaction

14. Erythroblastosis fetalis It is hemolytic disease in newborns Important complication of Rh incompatibility When Rh- ve mother carries an Rh+ve fetus

15. First pregnancy At the time of child birth when placenta detached some fetal RBCs enter in maternal blood, and mother form antibodies against these. First child is born normal : because delivery occurs before mother make antibodies

16. Next pregnancy During next pregnancy mothers antibodies cross placenta into fetus blood Where they cause agglutination and hemolyse Baby is born with hemolytic anemia If hemolysis severe fetus may die in uterus

17. Features Anemia Jaundice Spleen and liver are enlarged Bilirubin is deposited in basal ganglia with permanent brain damage Death occurs due to severe anemia

18. Management Know the father and mother blood group before delivery If father is positive & mother is negative – there is chance of hemolytic disease of newborn Give anti D antibody immediately following delivery - to cut natural immune reaction in mother for next pregnancies