Blood Transfusion Therapy (2023/2024) PDF

PHARMACOLOGY AND THERAPEUTICS II BLOOD TRANSFUSION THERAPY Catarina Jota Baptista Assistant Professor DVM, MSc, PhD in Veterinary Sciences [email protected] (based on the class of Prof Nuno Coelho, 20...

PHARMACOLOGY AND THERAPEUTICS II BLOOD TRANSFUSION THERAPY Catarina Jota Baptista Assistant Professor DVM, MSc, PhD in Veterinary Sciences [email protected] (based on the class of Prof Nuno Coelho, 2023/2024) BIBLIOGRAPHY Kohn, B.(2012). BSAVA Manual of Canine and Feline Haematology and Transfusion Medicine, 2nd edition. British Small Animal Veterinary Association. Banco de Sangue Animal. (2023) – Consulted in https://www.bsanimal.pt TABLE OF CONTENTS Introduction Donor selection considerations Types of blood transfusions Preparations for the transfusion Whole blood and components Clinical applications Clinical cases for you to solve INTRODUCTION Transfusion therapy: the transfer of blood or its components from a donor to a recipient. However, not only whole blood is used in transfusion, we can selectively choose which parts/components of the blood we want to transfer according to the specific conditions. Nowadays, blood bankings for animals are widely distributed and offer clear advantages in both convenience and possibility to address specific clinical conditions with specific hemocomponents. DONOR DONOR The conditions and specifications required and provided by the blood banks may vary. In BSA (Portugal) the donors are independently enrolled by their owners BSA guarantees the vaccination and parasiticide treatment and performs regular blood tests – complete blood count, biochemical analysis and infectious agent screening, namely: PCR for Ehrlichia spp, Anaplasma spp, Babesia spp, Leishmania spp and Brucella canis Serology for Ehrlichia spp, Leishmania spp and Dirofilaria immitis PCR for FeLV provirus, Mycoplasma haemofelis, Mycoplasma haemominutum, Mycoplasma turicencis and Bartonella spp. FeLV and FIV serology DONOR 15-20% of blood volume can be safely donated; standard donation: 450 ml; can donate every 3 weeks (if good nutrition), but usually not more than 4x/year restrained in lateral recumbence for jugular venipuncture observe for 15-30 minutes after donation for weakness, pale mucous membranes, weak pulse, and other signs of hypotension avoid excessive exercise for 4 days 15-20% of blood volume can be safely donated; standard donation: 50 ml in 4-5 kg cat - usually not more than 4x/year restrained in lateral/sternal recumbency for jugular venipuncture vasoconstriction is more pronounced in cats after venipuncture DONOR Before a blood transfusion, you need to check: Blood compatibility involves two components: The recipient’s blood type (e.g., DEA 1 in dogs, A/B/AB in cats). If the recipient has antibodies against the donor’s blood type. blood type This ensures the donor’s blood won’t be attacked by the recipient’s immune system. It’s called crossmatching to double-check compatibility presence of circulating antibodies specific for blood types that are not expressed by the patient’s RBCs Dogs have different blood types called DEA (Dog Erythrocyte Antigens). DEA 1 is the most important blood type because it can cause severe reactions if incompatible blood is given. All dog erythrocyte antigen (DEA) blood types are capable of stimulating the formation of antibodies. DEA 1 is considered the most clinically important in causing an acute reaction from transfusion of incompatible blood. The feline AB blood group system is relatively simple. Cats may be of blood group A, B or AB. DONOR DONOR DONOR  DONOR closed system: the only exposure of the bag or its contents to air prior to patient administration is when the needle is uncapped for venipuncture; no more exposure to external environment; sterilization. open system: there are more sites for potential transfusion rate: 5-10 ml/kg/hour, but the bacterial contamination; use of syringes (not first 15-30 minutes should have a lower bags); must be used in 4hours, stored in rate (0.25 ml/kg/hour) refrigerator for 24h or discarded DONOR DONOR Blood collection – anticoagulant (usually in the bag) An anticoagulant is required to prevent the blood from clotting during and after the donation. Sodium citrate is most commonly used, because the citrate chelates calcium, thereby inhibiting the coagulation cascade BLOOD PRODUCTS – FROZEN WHOLE BLOOD This is blood collected directly from a donor animal into a blood transfusion bag containing citrate- phosphate-dextrose with or without adenine (CPDA-1 or CPD) as an anticoagulant. All blood components (RBCs, platelets, labile and stable coagulation factors, plasma proteins) are present and functional. FWB should be restricted to those anaemic patients with concurrent haemostatic defects or uncontrolled bleeding  BLOOD PRODUCTS – PACKED RED BLOOD CELLS (PRBC) Concentrated blood cells are separated from the plasma by centrifugation. The unit must be collected in a bag with attached satellite bags to allow extraction and transfer of plasma in a closed system. Indications: replacement of blood cells that are capable of transporting oxygen to maintain tissue viability. When are PRBCs Used? haemolytic anaemia or non-regenerative anaemias To Replace Blood Cells: surgery– prior correction of anaemia or when large, intraoperative blood RBCs help transport oxygen to tissues, keeping them alive and healthy. In Specific Conditions: loss is expected; Hemolytic Anemia: RBCs are destroyed faster than they can be made. Non-Regenerative Anemia: The body isn’t producing enough RBCs. During Surgery: cardiopulmonary resuscitation, to increase oxygenation To fix anemia before surgery or to replace lost blood if there’s heavy bleeding during surgery. In Cardiopulmonary Resuscitation (CPR): To improve oxygen delivery during emergencies. ADVANTAGES OF PRBC OVER WHOLE BLOOD Avoids volume overload in patients that do not require plasma proteins. Avoids the risk of immune-mediated reactions to plasma proteins (the major cause of transfusion reactions). Avoids wasting unnecessary components that can be used in other patients Allows longer erythrocyte storage time (up to 6 weeks instead of 4 weeks in whole blood). Prevents Volume Overload: PRBCs contain only red blood cells, making them ideal for patients who don’t need plasma proteins. Avoids giving excess fluid, which could stress the heart or lungs. Reduces Risk of Plasma-Related Reactions: Plasma proteins in whole blood can cause immune-mediated reactions, the most common type of transfusion reaction. PRBCs minimize this risk by removing plasma. Minimizes Wastage: By separating blood into components (e.g., plasma, platelets, PRBCs), each part can be used for different patients, maximizing utility. Longer Storage Time: PRBCs can be stored for up to 6 weeks, compared to 4 weeks for whole blood, making inventory management easier. BLOOD PRODUCTS – PLATELET CONCENTRATE Platelet-rich plasma (PRP) and platelet concentrate (PC) may be prepared from WB; however, these products are some of the most challenging to prepare owing to the nature of platelets. PC is not recommended in patients without active bleeding, except as prophylaxis for invasive procedures. Indications: Primary haemostatic disorders: Severe thrombocytopenias: bone marrow disorders, DIC, neoplasia, immune-mediated or infectious agents (e.g. Ehrlichia spp., Anaplasma spp.); Congenital thrombocytopathies (e.g. Glanzmann's disease) or acquired (e.g. NSAIDs, clopidogrel, uremia, liver failure); Prophylaxis in patients with thrombocytopenia or thrombocytopenia submitted to invasive procedures (e.g. biopsy, surgery, endoscopy). BLOOD PRODUCTS – FRESH FROZEN PLASMA (FFP) Fresh frozen plasma (FFP) is plasma separated from PRBC and frozen within 8 hours. FFP provides maximum quantities of the labile coagulation factors V and VIII and von Willebrand factor, as well as all other coagulation factors and plasma proteins. BLOOD PRODUCTS – FRESH FROZEN PLASMA (FFP) Indications: Plasma protein deficiency including labile coagulation factors, von Willebrand factor, fibrinogen, albumin, immunoglobulins, antithrombin and protease inhibitors (e.g. α–2–macroglobulin) Volume and clotting factor replacement in massive transfusions; Congenital coagulopathies: haemophilia A, haemophilia B, von Willebrand disease, hypofibrinogenemia, etc. Acquired coagulopathies: rodenticide poisoning, liver disease, severe cholestasis, DIC or coagulopathy due to acute trauma, hyperfibrinogenemia; Colloidal support in patients with refractory hypotension or severe hypoalbuminemia; Altered vascular permeability and inflammation in critically ill patients with severe SIRS (e.g. sepsis, necrotising pancreatitis, parvovirus, panleukopenia, acute trauma with haemorrhagic shock and blood failure); Passive immunity deficiency BLOOD PRODUCTS – STORED FROZEN PLASMA (SFP) Stored frozen plasma (SFP) is FFP > 1 year of age, or FFP that has been thawed and refrozen without opening the bag, or plasma not frozen quickly enough to fully protect labile factors. Some loss of clotting factors and anti-inflammatory proteins will have occurred. SFP can be used for colloidal support (in hypoproteinemia) and still provides vitamin K-dependent factors (which are not labile) to treat vitamin K deficiency or vitamin K antagonist poisoning. SFP may be stored frozen at –20°C for 5 years from the date of collection BLOOD PRODUCTS – CRYOPRECIPITATE Preparation of cryoprecipitate (Cryo) provides a source of concentrated von Willebrand factor, FVIII, FXIII, fibrinogen and fibronectin from a unit of FFP by collecting the cold- insoluble proteins (precipitate). Allows for the replenishing of the necessary clotting factors without transfusing large amounts of WB or P. This reduces the risk of volume overload or transfusion reactions and optimises the use of blood components. Indications: Von Willebrand’s disease – treatment or prevention in invasive procedures; Haemophilia A (factor VIII deficiency) – treatment or prophylaxis in invasive procedures; Hyperfibrinolysis and hypofibrinogenemia (acute trauma, liver disease, DIC, angiostrongylosis…). The goal is to maintain the fibrinogen > 1,5 g/dL. BLOOD PRODUCTS – CRYOSUPERNATANT Preparation of cryosupernatant refers to plasma from which the cryoprecipitate has been removed. Cryosupernatant is useful for the same indications as FFP, except von Willbrand's disease, haemophilia A and hyperfibrinolysis or hypofibrinogenemia states. Indications: Severe hypoalbuminemia (