Transfusion Reactions Quiz

Transfusion Science - Transfusion Reactions

• Transfusion science focuses on the safe administration of blood products.
• Transfusion reactions are adverse events resulting from blood transfusions.
• Preparation for the lecture includes reviewing the NHSBT lecture and having coffee.
• The aim is to discuss compatibility testing and different types of transfusion reactions.
• Key learning objectives include understanding cross-matching, the range of possible reactions, and blood bank laboratory investigation methods.

Blood Grouping

• Blood grouping is crucial for compatibility testing.
• Nine major blood group systems exist in humans (ABO, MNS, Rh, Lutheran, Kell, Lewis, Duffy, Kidd, P).
• Each system is characterized by specific antigens on red blood cell surfaces.
• Blood grouping is based on the presence or absence of these antigens.

ABO Antigens and Landsteiner's Law

• ABO antigens are located on chromosome 9.
• Inheritance follows an autosomal dominant pattern.
• Landsteiner's Law states: If an antigen is present, the corresponding antibody is absent.
• The ABO system is unique; antibodies are always present.
• Blood types are characterized by the presence or absence of A and/or B antigens.

Acceptance Criteria

• Samples and request forms must be labeled immediately and contain the following minimum identifiers: forename, surname, date of birth, hospital number, sample date, and collection time.
• The request form must be signed.
• Zero tolerance policy for errors

Cross-Matching

• Red cell transfusions are common for various reasons, including blood loss, surgery and anaemia.
• Compatibility testing involves grouping and antibody screening.
• ABO and Rh D blood groups are determined.
• Patient serum is screened for the presence of clinically significant antibodies.
• Electronic cross-matching uses LIMS (Laboratory Information Management System).
• Matching ABO and RhD with historical records
• Checking antibody screen results
• Checking historical and current negative antibody screens

Immediate Spin Cross-Matching

• Donor red blood cells are prepared by arranging and labelling the gel card
• A 0.8% red cell suspension from donor red blood cells is produced.
• 50 µl of the red cell suspension is added to the card's wells.
• 25 µl of patient plasma is added to the wells.
• Incubated at 37 °C for 15 minutes.
• Centrifugation is used to detect agglutination (antibody binding).

Cross-Matching (further detail)

• Compatibility between a unit of blood and the patient must be ensured.
• Patient location, type, amount, date, and time specifications are needed.
• Special requirements like CMV negativity or irradiation must be indicated.
• Signature and name of the requestor are required
• Usually takes 35-40 minutes
• Unit details are printed correctly on labels and attached to the blood pack.
• The unit is then placed in the issue fridge.

Indirect Coombs test

• Recipient serum containing antibodies is obtained.
• Donor blood is added to the serum.
• The recipient’s antibodies target the donor red blood cells forming antibody-antigen complexes.
• Anti-human antibodies are added to the solution.
• Agglutination of red blood cells indicates a positive test

Transfusion Reactions (Types)

• Acute Haemolytic Reaction
• Delayed Haemolytic Transfusion Reaction
• Unit contamination with bacteria
• Severe Allergic Reaction
• Transfusion Associated Acute Lung Injury (TRALI)
• Transfusion Associated Circulatory Overload (TACO)
• Post-transfusion purpura (PTP)
• Non-haemolytic Febrile Transfusion Reaction (NHFTR).

Acute Transfusion Reaction

• Symptoms occur within 30-60 minutes of transfusion.
• The transfusion involves red blood cells that elicit an antibody response.
• Rapid destruction of donor cells releases cytokines.
• Common symptoms include fever, chills, pain, vomiting, tachycardia, hypotension, DIC, and shock.
• The transfusion should be stopped immediately.

Delayed Transfusion Reaction

• Symptoms occur 12-36 hours later (or even weeks later).
• The patient's antibody against an erythrocyte antigen may have decreased to undetectable levels.
• Less common, but still possible blood group antigens are targeted.
• Patient's haemoglobin level will decrease. Possible symptoms include jaundice, malaise, mild fever, and/or increased antibody level and haemolysis for approximately 2 weeks following blood transfusion

Bacterial Infections

• Bacterial infections in blood products can occur during collection, processing and storage.
• Most frequently affect platelets.
• Short expiry dates increase the risk.
• Blood products may appear cloudy, have unusual colours, or show aggregates as symptoms.

Allergic Reaction

• Allergic reactions can range from mild urticaria to severe anaphylaxis.
• Patients with IgA deficiencies are more susceptible.
• Type I hypersensitivity mechanism is common.
• The risk is minimized by using red cell & platelet products from donors who lack IgA or through plasma washing (removal of plasma)

Transfusion Related Acute Lung Injury (TRALI)

• Occurs within 6 hours after transfusion.
• Symptoms include sudden acute respiratory distress, hypoxia, and fever.
• Donor blood antibodies react with recipient neutrophils
• Damage to capillaries leads to fluid leaking into the alveolar spaces.
• Diagnosis is mainly through exclusion, ruling out other causes such as acute transfusion or myocardial infarction.
• Associated with approximately 10% morality

Transfusion-Associated Circulatory Overload (TACO)

• A condition arising from rapid transfusion of large volumes of blood products over a short period.
• A significant risk exists for patients over age 60.
• Clinicians often mistake TACO for TRALI.
• Patients exhibit hypertension, tachycardia, respiratory distress, and pulmonary edema.
• Prevention of TACO involves careful monitoring and slower transfusion rates.

Role of the Blood Transfusion Laboratory

• STOP the transfusion immediately when any reaction is suspected!
• Laboratory is contacted immediately with patient details and symptoms
• Transfused and unused units are sent for re-testing.
• Pre-transfusion samples are re-tested.
• Post-transfusion samples are tested.

Role of the Blood Transfusion Laboratory (Reporting)

• Reporting of transfusion reactions, adverse events, and incorrect procedures.
• SABRE (Serious Adverse Blood Reactions and Events) - MHRA reporting system.
• SHOT (Serious Hazards of Transfusion) - data collection and recommendations for improved patient safety.

Case Studies

• Case studies (1-3) illustrate real-world scenarios of transfusion errors and their consequences.
• Errors included incorrect labeling, communication failures, and incorrect pre-administration checks during blood collection processes, resulting in transfusion reactions.

Summary

• Incorrect transfusions pose a significant morbidity and fatality risk.
• Zero tolerance error policies are implemented.
• Human error is a significant cause of transfusion-related incidents with a year-over-year increase in errors.
• Investigating transfusion incidents/near misses contributes to data collection for improving blood transfusion safety.
• Adverse reactions persist as under-reported cases.

Test your knowledge on Transfusion Associated Circulatory Overload (TACO) and related adverse transfusion reactions. This quiz covers clinical signs, at-risk populations, immediate actions required during transfusion reactions, and diagnostic acronyms. Perfect for healthcare professionals and students in the medical field.