12- Blood transfusion Dr. wesam

Page 2: Background

First Blood Transfusion:In June 1667, pioneering physicians Jean-Babtiste Denis and Paul Emmerez performed the first documented blood transfusion, transferring sheep blood into a 15-year-old boy suffering from hemorrhagic fever. While initial reports indicated success, subsequent complications arose, leading to fatal outcomes and the eventual criminal prosecution of Dr. Denis due to adverse reactions. This event highlighted the need for rigorous scientific understanding and ethical guidelines in transfusion practices.

Blood Groups Discovery:In 1900, Karl Landsteiner made a groundbreaking discovery when he identified the three major blood groups: A, B, and O. This discovery laid the groundwork for the modern field of transfusion medicine. Later, in 1939, the Rh blood group system was recognized, further enhancing the understanding of blood compatibility and transfusion safety.

Page 3: Indications for Blood Replacement

Severe Anemia:Transfusion is indicated in cases where urgent correction of diminished oxygen-carrying capacity is required, particularly in severe anemia due to chronic diseases or acute blood loss.

Volume Replacement:The most common indication for transfusion is volume replacement, necessary after significant blood loss from trauma, surgery, or other medical conditions that compromise blood volume.

Clotting Factor Replacement:Transfusions may be necessary to replace specific clotting factors in patients with bleeding disorders (e.g., hemophilia) or prior to or during surgical procedures where hemostatic control is critical.

Page 4: Preservation and Storage of Blood

Blood is collected aseptically, using strict protocols to prevent contamination. It is mixed with anticoagulants (such as CPDA-1) and stored in sterile plastic bags.

Storage Temperature:Optimal storage temperature is 4°C to preserve cellular integrity and function. Blood that has been kept at room temperature for more than 30 minutes prior to transfusion should be discarded, reducing the risk of bacterial growth and potential infections.

Page 5: Blood Composition and Stability

Unit Composition:A typical blood unit (approximately one pint) consists of about 450 ml of whole blood and 63 ml of CPDA-1. Each unit contains essential components like approximately 10 grams of albumin, 2 grams of gamma globulin, and 0.5 grams of fibrinogen, all vital for maintaining hemostasis and immune function.

Storage Stability:Factors VII and VIII are unstable at refrigerative temperatures (5°C), while they remain stable in fresh frozen plasma (FFP) and cryoprecipitate when stored at -30°C. Generally, red blood cells (RBCs) have a survival rate of 70-80% after five weeks of storage. It's important to note that granulocytes lose viability in stored blood and are ineffective once transfused, thus necessitating the use of fresh blood when possible. Each pint of transfused blood can raise a patient's hemoglobin level by approximately 1 g/dl, which is crucial for assessing the effectiveness of the transfusion.

Page 6: Adverse Consequences of Blood Transfusion

Immune Complications:

  • Immediate Hemolytic Transfusion Reaction: Often caused by ABO incompatibility, can manifest as fever, chills, and back pain.

  • Delayed Hemolytic Transfusion Reaction: Occurs days to weeks after transfusion, leading to a gradual decrease in hemoglobin levels.

  • Non-Hemolytic Febrile Transfusion Reaction: Results from recipient's immune response to donor white blood cells or cytokines.

  • Anaphylactic Shock: Rare but severe allergic reaction may occur in sensitized individuals.

Transmission of Infection:Transfusion carries risks of infections, such as:

  • Bacterial infections: Can occur if contaminated blood products are used.

  • Viral infections: Include Hepatitis B, Hepatitis C, and HIV.

  • Protozoal infections: Rare, but can result from transfusion of infected red cells.

Page 7: Other Complications

Non-Immune Complications:These include:

  • Immunosuppression: Transfusion can suppress recipient immune response.

  • Circulatory Overload: Particularly dangerous for patients with heart failure.

  • Iron Overload: Excessive transfusions lead to accumulation of excess iron in organs.

  • Graft Versus Host Disease (GVHD): A rare but serious condition, particularly in immunocompromised patients.

  • Air Embolism: Occurs if air enters the circulatory system during transfusion.

  • Thrombophlebitis: Inflammation of the vein can occur post-transfusion.

Page 8: Massive Transfusion

Defined as a transfusion volume exceeding the recipient's total blood volume within 24 hours. It typically involves administering blood-group-specific compatible whole blood or red cells.Rapid Administration Tools:Utilization of pressure infusers or pumps, along with blood warmers, is crucial for safe and rapid infusion, especially in trauma cases. Additionally, FFP and platelet concentrates may be necessary to maintain hemostatic balance during massive transfusions.

Page 9: Complications of Massive Transfusion

Potential Complications:

  • Cardiac Abnormalities: Risk of low temperature, excess citrate from anticoagulants, high potassium levels, and low calcium can lead to arrhythmias.

  • Acidosis: Can occur due to the metabolic response to large volume infusions.

  • Failure of Hemostasis: This may arise from inadequate levels of coagulation factors and platelets.

  • Acute Respiratory Distress Syndrome (ARDS): A serious complication that can develop after massive transfusions.

Page 10: Blood Constituents for Clinical Use

Available Products:

  1. Whole Blood: Rarely used; mainly in trauma.

  2. Blood Components:

    • Red Cells: Available in various preparations.

    • Platelets: Supplied as single units, pooled, or collected via a cell separator.

    • White Cells: May be provided in specific conditions.

    • Fresh Frozen Plasma: Contains clotting factors and is crucial for managing coagulopathy.

    • Cryoprecipitate: Rich in fibrinogen, useful in bleeding patients.

  3. Plasma Products:

    • Human Albumin Solution (5%, 20%, salt-poor): Used to maintain oncotic pressure.

    • Coagulation Factors Concentrate (Factor 8 & 9): Essential for patients with hemophilia.

    • Immunoglobulins: Used for immune therapy.

Page 11: Plasma Substitutes

Types:

  • Dextran

  • Haemacel

  • Hetastarch

Advantages:These agents offer:

  • Longer Circulation Times: Up to 6 hours for Haemacel, 12 hours for Dextran, and 24 hours for Hetastarch.

  • Non-Toxic: Generally safe for use and do not require blood for compatibility testing.

  • Storage: Room temperature storage reduces logistical challenges.

  • Low Risk of Infection Transmission: As they are synthetic products.

Side Effects:

  • Potential allergic reactions including fever and rash.

  • Anaphylaxis in rare cases, particularly with Dextran.

  • Dextran may also interfere with compatibility testing.

Page 12: Precautions Before and During Transfusion

  1. Donor Selection:

    • Ensure donors are rigorously screened for infections such as Hepatitis, HIV, Malaria, and Syphilis to prevent transmission through transfusion.

  2. Grouping & Cross-Matching:

    • Accurate blood type determination and cross-matching must be performed to prevent severe transfusion reactions.

  3. Labeling:

    • Blood containers should be labeled distinctly to avoid mix-ups, with emphasis on donor type and expiration dates.

  4. Storage:

    • Blood products must be stored at 4°C and discarded after 5 weeks to maintain quality and safety.

  5. Contamination:

    • Strict protocols should be in place to prevent the use of blood suspected of contamination.

  6. Recipient Monitoring:

    • Recipients must be monitored for signs of incompatibility, allergic reactions, fluid overload, and manage any adverse effects promptly.

Page 13: Blood Group Compatibility

Giving and Receiving Blood:

  • O: Universal donor (can receive O- only)

  • A: Can receive from A, A+, O, O+

  • B: Can receive from B, B+, O, O+

  • AB: Universal receiver (can receive from all groups)

Compatibility details should be strictly adhered to for safety.

Page 14: Blood Group Frequencies

  • O+: 47%

  • A+: 26%

  • B+: 9%

  • O: 8%

  • A: 5%

  • B-: 2%

  • AB+: 2%

  • AB: 1%

Understanding these frequencies is important for blood donation drives and transfusion planning.