1. BLOOD GROUP SYSTEMS. Page 1. Haematology LECTURE 10. BLOOD GROUPS AND TRANSFUSIONS OVERVIEW. 1. Blood Group Systems

Size: px

Start display at page:

Download "1. BLOOD GROUP SYSTEMS. Page 1. Haematology LECTURE 10. BLOOD GROUPS AND TRANSFUSIONS OVERVIEW. 1. Blood Group Systems"

Alexander Curtis
8 years ago
Views:

1 Undergraduate Course in Veterinary Clinical PathologySocrates Programme Haematology LECTURE 10. BLOOD GROUPS AND TRANSFUSIONS 10-1 OVERVIEW 1. Blood Group Systems 2. Blood group testing and cross-matching 3. Definition, aims and indications for blood transfusion BLOOD GROUP SYSTEMS 10-3 Page 1

2 BLOOD GROUP SYSTEMS In Simple Terms: Blood groups are determined according to the antigens expressed on the erythrocyte Combinations of blood groups make up a blood group system HOWEVER: Antibodies against different blood group antigens are extremely important in determining the success or failure of a blood transfusion 10-4 RED BLOOD CELL ANTIGENS: GENERAL CHARACTERISTICS - Generally glycoproteins or glycolipids anchored to the surface of the erythrocyte - Usually detected by antibodies (naturally occurring or induced by deliberate immunisation) - Grouped in blood group systems encoded by alleles at single or multiple gene loci 10-5 BLOOD GROUP ANTIBODIES: GENERAL FEATURES - The presence of antibodies directed against RBC antigens will reduce survival of transfused cells (transfusion reaction) - Some species have high titres of naturally-occurring antibodies which may cause transfusion reactions after the first transfusion - Antibodies can be induced following a transfusion. Therefore the risk of transfusion reactions in subsequent transfusions is greater - Neonates can receive these antibodies in colostrum causing neonatal isoerythrolysis 10-6 Page 2

3 BLOOD GROUP SYSTEMS: DOGS - Dogs have 14 blood groups determined by the Dog Erythrocyte Antigens (DEA) - DEA 1.1, DEA 1.2, and DEA 7 are the most immunogenic - Naturally occcuring antibodies are rare - Reactions rarely occur after first un-matched transfusions nomenclature DEA Blood group prevalence in dogs (%) 1.1 (A) (B) 6 4 (C) (D) 22 6 (F) (Tr) (o) 31 J 34 K 2 L 51 M 19 N BLOOD GROUP SYSTEMS: CATS - Cats have A, B and rarely AB blood groups - Prevalence of blood groups varies between countries and with breed Blood Reaction Natural antibodies blood group in serum group with type frequency prevalence A anti-a anti-b rare very high 80-90% B anti-b anti-a high low 10-20% AB anti-a & absent absent rare anti-b Transfusion reactions can occur after first transfusion due to naturally occurring antibodies 10-8 BLOOD GROUP SYSTEMS HORSE - Horses have up to 33 different blood groups belonging to 7 systems - Aa, Qa, and Ca are the most immunogenic blood groups CATTLE - Cattle have up to 70 different blood groups belonging to 11 systems - The J blood group system is not a true RBC antigen but adsorbed from plasma Alloantibodies are produced following transfusion in at least 50% of recipients 10-9 Page 3

4 2. BLOOD GROUP TESTING (BLOOD TYPING) AND CROSS-MATCHING BLOOD GROUP TESTING (BLOOD TYPING) - Detects the antigens pattern on the erythrocyte surface using polyclonal or monoclonal antisera - Does not determine the presence of antibodies BLOOD GROUP TESTING: DOGS AND CATS THIS DOG IS NEGATIVE FOR DEA 1.1 THIS CAT IS TYPE AB (RARE) Page 4

5 BLOOD GROUP TESTING HORSE AND/OR COW AGGLUTINATION TEST HAEMOLYSIS TEST BLOOD CROSS-MATCHING (BCM) Assess blood compatibility between the donor and the recipient A simple technique without any specific reagent Major cross-match detects if the recipient s serum contains any antibodies against the donor s RBCs Minor cross-match detects if the donor s serum contains any antibodies against the recipient s RBCs CROSS MATCHING TECHNIQUE - Collect a blood sample both from donor and recipient into anticoagulant (EDTA or heparin) - Centrifuge the samples, remove and retain the plasma - Resuspend RBCs in saline, centrifuge, and discard the supernatant; repeat 3 times (washed RBC). - Prepare a 3-5% RBC suspension with saline MINOR CROSS-MATCH Mix recipient RBC suspension with plasma from the donor (ie two drops each) MAJOR CROSS-MATCH Mix donor RBC suspension with plasma from the recipient (ie two drops each) - Incubate at 3 different temperature (37 C, 20 C, and 4 C) - Check after minutes for haemolysis and/or agglutination by visual inspection or eventually microscopically Page 5

6 Haem Haem Cont Aggl Cont Aggl CROSS-MATCH (CM) TEST ON SLIDES CROSS-MATCH (CM) TEST ON TUBES DEFINITION, AIMS AND INDICATIONS FOR BLOOD TRANSFUSION BLOOD TRANSFUSION: DEFINITION AND AIMS Definition: A form of temporary organ transplantation Must respect the blood group systems of the species and the individual A useful symptomatic treatment in many blood disorders Aims: - Supplying oxygen to body tissue - Restoring the blood volume Page 6

7 BLOOD TRANSFUSION: MAIN INDICATIONS - Severe and/or acute anaemia: Haemorrhagic Haemolytic Non regenerative - Severe coagulopathy - Severe thrombocytopenia BLOOD AND BLOOD PRODUCTS - Whole Blood: fresh or stored (FWB or SWB) - Packed Red Blood Cells (PRBC) -Plasma: fresh frozen (FFP) frozen (FP) cryoprecipitate (Cryo) + cryosupernatant - Platelet rich plasma or concentrate (PLTC) BLOOD AND BLOOD PRODUCTS: ACTIVITIES Source of or activity FWB SWB PRBC FFP FP PLTC Cr yo Supernatant RBC Album in / PLT FII,VII,IX,X FVIII,vWF /- ATI I I other / proteins Page 7

INDICATIONS FOR BLOOD PRODUCT TRANSFUSIONS

INDICATIONS FOR BLOOD PRODUCT TRANSFUSIONS Sarah Perry, LVT, BS, VTS (ECC) Licensed Veterinary Technician Animal Neurology, Rehabilitation and Emergency Center 1120 Welch Rd. Commerce, MI 48390 A very