Complication and hazard of Blood transfusions

Complication and hazard of Blood transfusions are lifesaving procedures, but they are not without risks. Although most transfusions are safe and effective, complications and hazards can arise, ranging from mild to life-threatening. These complications can occur during the transfusion (acute) or days to weeks later (delayed).

Types of Complications and Hazards

1. Immunologic Reactions

These reactions are caused by immune responses to donor blood components.

• Acute Hemolytic Transfusion Reaction (AHTR):
  • Cause: ABO or Rh incompatibility between donor and recipient blood. It occurs when the recipient’s immune system attacks the donor’s red blood cells.
  • Symptoms: Fever, chills, chest or back pain, nausea, shortness of breath, hypotension, and dark urine due to hemolysis (destruction of RBCs).
  • Risk: This can lead to shock, kidney failure, disseminated intravascular coagulation (DIC), and even death.
  • Prevention: Proper blood typing, crossmatching, and compatibility testing.
• Febrile Non-Hemolytic Transfusion Reaction (FNHTR):
  • Cause: Immune response to donor white blood cells or cytokines.
  • Symptoms: Fever, chills, headache, and malaise. It is usually mild and self-limiting.
  • Prevention: Use leuko-reduced blood (blood with most white blood cells removed).
• Allergic Reactions:
  • Cause: Allergic response to plasma proteins in donor blood.
  • Symptoms: Hives, itching, swelling, and, in severe cases, anaphylaxis (a life-threatening allergic reaction involving airway constriction).
  • Prevention: Use antihistamines before transfusion and, in severe cases, wash the donor blood to remove plasma proteins.
• Delayed Hemolytic Transfusion Reaction (DHTR):
  • Cause: An immune response that develops days or weeks after transfusion due to undetected minor antibodies (e.g., antibodies against antigens like Kell, Kidd, or Duffy).
  • Symptoms: Mild fever, anaemia, jaundice, dark urine.
  • Risk: Can cause mild hemolysis and anaemia but rarely severe complications.
  • Prevention: screening for minor antibodies.
• Transfusion-Related Acute Lung Injury (TRALI):
  • Cause: Interaction between donor plasma and recipient leukocytes, causing an inflammatory reaction in the lungs.
  • Symptoms: Sudden onset of respiratory distress, hypoxemia (low blood oxygen), fever, and pulmonary oedema (lung fluid).
  • Risk: It can be life-threatening and requires immediate medical intervention.
  • Prevention: Use of plasma from male donors or female donors who have never been pregnant to reduce the risk.

2. Infectious Complications

Although screening of blood donors and blood products has greatly reduced the risk, infectious diseases can still be transmitted via transfusion.

• Bacterial Contamination:
  • Cause: Contamination of blood products, especially platelets, stored at room temperature.
  • Symptoms: High fever, chills, shock, and sepsis.
  • Risk: This can lead to life-threatening infections and septic shock.
  • Prevention: Proper screening, blood collection, and storage protocols.
• Viral Infections:
  • Cause: Transmission of viruses such as:
    • Hepatitis B and C: Can cause chronic liver disease and liver cancer.
    • HIV: This can lead to acquired immunodeficiency syndrome (AIDS).
    • HTLV (Human T-lymphotropic Virus): Associated with leukaemia and neurological conditions.
    • West Nile Virus, Zika Virus: Emerging viral risks.
  • Prevention: Blood donor screening and nucleic acid testing (NAT) for viral detection.
• Parasitic Infections:
  • Cause: Transmission of parasites like malaria or Babesia.
  • Symptoms: Fever, anaemia, and, in severe cases, organ failure.
  • Prevention: Screening and deferral of donors from high-risk areas.

3. Circulatory Overload

• Cause: Rapid or excessive transfusion of blood volume, particularly in patients with heart or kidney conditions.
• Symptoms: Shortness of breath, high blood pressure, pulmonary oedema, and heart failure.
• Risk: Can be life-threatening if not treated.
• Prevention: Careful monitoring of transfusion rates, especially in elderly patients and those with cardiovascular or renal problems.

4. Iron Overload (Transfusion Hemosiderosis)

• Cause: Accumulation of excess iron from repeated transfusions, particularly in patients with chronic anaemia (e.g., thalassemia, sickle cell disease).
• Symptoms: Fatigue, liver damage, heart failure, diabetes, and hormone imbalances.
• Prevention: Use iron chelation therapy (medication to remove excess iron from the body) in patients requiring regular transfusions.

5. Graft-versus-Host Disease (GVHD)

• Cause: Donor white blood cells (lymphocytes) attack the recipient’s tissues, particularly in immunocompromised patients.
• Symptoms: Fever, rash, diarrhoea, liver dysfunction, and bone marrow failure.
• Risk: Rare but often fatal.
• Prevention: Use of irradiated blood to destroy donor lymphocytes, especially in at-risk populations (e.g., newborns, cancer patients, and those with immune disorders).

6. Metabolic Complications

• Hyperkalemia: Increased potassium levels in the blood due to leakage of potassium from stored red blood cells, which can lead to heart arrhythmias.
• Hypocalcemia: Low calcium levels caused by anticoagulants (such as citrate) used in stored blood products binding to calcium, potentially causing muscle spasms or cardiac issues.
• Acidosis: Low blood pH due to buildup of acidic metabolites from transfused blood.

7. Non-Immunologic Hemolysis

• Cause: Mechanical damage to donor red blood cells, improper storage, or blood infusion through a faulty IV line.
• Symptoms: Hemoglobinuria (haemoglobin in the urine), anaemia, kidney damage, and jaundice.

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Prevention and Mitigation of Risks

1. Blood Typing and Crossmatching: Accurate ABO and Rh typing and crossmatching help prevent serious hemolytic reactions.
2. Leukoreduction: Removing white blood cells from donated blood reduces the risk of febrile reactions and immune-mediated complications.
3. Irradiation: Prevents graft-versus-host disease by destroying donor lymphocytes.
4. Antibody screening: Identifies unexpected antibodies that could cause hemolysis.
5. Blood Donor screening: Ensures safe blood by screening for infectious diseases and deferring high-risk donors.
6. Monitoring: Close monitoring during transfusions helps detect and manage reactions early.
7. Blood Storage and Handling: Proper storage and handling of blood products minimize the risk of contamination and hemolysis.