Blood Transfusion Reactions and Clotting Time (Physiology Part 1 PDF)

Lab no. 5 Blood Transfusion Reactions.Aim: To learn the physiology bases behind transfusion reactions The surface of human RBC at least 100 of antigens, any of which can ❖ cause antigen antibody reactions if reacted with a proper antibody. Most of these antigens are weak, but import fo...

Lab no. 5 Blood Transfusion Reactions.Aim: To learn the physiology bases behind transfusion reactions The surface of human RBC at least 100 of antigens, any of which can ❖ cause antigen antibody reactions if reacted with a proper antibody. Most of these antigens are weak, but import for studying the inheritance of genes. Two types of antigens can cause blood transfusion reactions; the O-A-B and Rh system. The RBC of type A a surface A antigen, that of type B a surface B antigen and that of type AB both A and B surface antigens; while RBC of type O neither A nor B surface antigens. To discover type of antigen on RBCs and determine type of blood used.blood group kit Human blood contains antibodies (immunoglobulins of type “IgG” or ❖ “IgM”) against A or B antigens. Type A blood contain anti-B antibodies, type B contain anti-A antibodies, type O contain anti-A and anti-B.antibodies; while type AB contain neither anti-A nor anti-B antibodies In some cases, and some diseases introduction “transfusion” of blood is ❖.essential saving the life Transfusion reaction is an antigen-antibody reaction in which the IgG or ❖ IgM antibodies cross more than two RBCs “clumping” together” ended.with RBCs hydrolysis and loss of their functions Rh Blood Group D antigen ❖ Type Rh+ (positive) blood: Rh antigens on cell Type Rh- (negative) blood: no Rh antigens on cell To discover type of blood used blood group kit Blood group test MATERIAL fresh blood.1 Blood group kit.2 slid.3 Stick.4 lancet.5 Procedure Unpack the ABD kit. In the first circle add Anti-A, to the second circle.add Anti-B and to the third circle add Anti-D with the help of a dropper.Keep the slide aside safely without disturbing Now wipe the ring finger with the alcohol swabs and rub gently near the.fingertip, where the blood sample will be collected Prick the ring fingertip with the lancet and wipe off the first drop of the.blood As blood starts oozing out, allow it to fall on the three circles of the glass slide by.gently pressing the fingertip Apply pressure on the site where it was pricked and to stop blood flow. Use the.cotton ball if required Mix the blood sample gently with the help of a stick and wait for a minute to.observe the result  :Apply Why is it important to know an individual’s blood type? ?Could knowing your own blood type impact your health ?What are the materials required to determine blood groups ▪ ?Discuss the procedure by which blood group test done ▪ ?What are the antigen-antibody reactions ▪ Lab no. 6 Determination of clotting time (PT) and bleeding time (BT) Aim: To learn how to estimate clotting time and bleeding time of human and its relation to blood function and human health. In order for blood to clot, the enzyme thrombin must be generated from the plasma precursor prothrombin. Thrombin then converts soluble fibrinogen into insoluble fibrin. Generation of thrombin involves the sequential activation of a number of other plasma clotting factor, this process is also being assisted by Ca+2 and by factors released by platelets (phospholipids) and damaged tissues (collagen). Depending on the type of vascular damage or abnormality, clotting can be initiated and proceed according to two different cascading pathways: the intrinsic (initiated by contact with and abnormal/foreign surface, e.g.; atherosclerosis) or the extrinsic (initiated by exposure to tissue collagen). The time taken for blood to clot mainly reflects the time required for the generation of thrombin in this manner hence clotting time is also referred to as prothrombin time (PT). If the plasma concentration of prothrombin or of some of the other factors is low (or if the factor is absent, or functionally inactive), clotting time will be prolonged. The time taken for blood vessel constriction and platelet plug formation is referring to the bleeding time (BT); at this time no clot is allowed to form, so that the arrest of bleeding depends exclusively on blood vessel constriction and platelet action. These two tests are used in testing and monitoring normal and abnormal function of the hemostatic system in healthy and diseased peoples. Experiment Materials Human Volunteer Lancet Filter papers Glass slide Non-heparinized capillary tubes Timer Procedure Preparation: 1. Make sure that the volunteer has no liver diseases, not on anticoagulant medications (heparin, enoxaparin, aspirin, warfarin, clopidogrel, rivaroxaban, dabigatran, apixaban or edoxaban) 2. Make sure that the volunteer has no liver diseases and no inflammation and has normal platelets count. Application: Clotting time (PT): Slide method 1. Prick the finger with the lancet. 2. Put a free flowing blood on the slide. 3. Every 30 sec. pull the blood up with a lancet tip or needle syringe 4. When a clot starts forming, that is the endpoint and clotting time. Clotting time (PT): Capillary method 5. Prick the finger with the lancet. 6. Hold the capillary over the blood, and the capillary will fill automatically. 7. Now, after regular intervals, break the capillary. 8. When a clot starts forming, that is the endpoint and clotting time. Bleeding time (BT): Duke's method 1. Swab the volunteer’s fingertip with alcohol 2. Prick the fingertip with a special needle or lancet (The prick is about 3– 4 mm deep) 3. Mark a filter paper in clockwise direction with (0, 30, 60, 90, 120, 150, 180, 210 and 240sec) 4. The volunteer then wipes the blood every 30 seconds on the corresponding time mark on the filter paper. 5. The test ceases when bleeding ceases. Normal Result: 1. The normal range for clotting time (PT) is 6-10 mins. 2. The normal range for bleeding time (BT) is 2-5 mins. Factors effecting PT and BT 1. The bleeding time test may be affected by anticoagulants that are used by the person. 2. Hence if the person is on any medication or supplement or herbs, this should be immediately informed to the specialist. 3. Also, a diet full of green and leafy vegetables may affect the clotting time. If the person has very low platelet count, then the BT test should not be done on the person. Also, people who have lymph nodes dissected should not undergo the BT.4 test. The scars that are made for the BT test remain visible for a long time in.people who tend to have keloids Clot Formation: 1. Primary Clot 2. Secondary Clot Note: clotting factor: The liver must be able to use Vitamin K to produce Factors II, VII, IX, and X 1. Factor I - fibrinogen: liver 2. Factor II – prothrombin: liver 3. Factor III - tissue thromboplastin (tissue factor): liver endothelium 4. Factor IV - (Ca++): GIT 5. Factor V - labile factor or proaccelerin: liver pletelate 6. Factor VI - unassigned 7. Factor VII - stable factor or proconvertin: liver 8. Factor VIII - ant hemophilic factor endothelium : 9. Factor IX - plasma thromboplastin component, Christmas factor: liver 10. Factor X - Stuart-Prower factor: liver 11. Factor XI - plasma thromboplastin antecedent liver :  Factor XII - Hageman factor: liver.12 Factor XIII - fibrin-stabilizing factor.13 :Apply ? Describe how clotting is occurring ? What factors cause the bleeding to stop after injury ? What is the normal range of platelets in human ? What are the roles of platelets in stopping the bleeding