What risks should be discussed with patients regarding blood transfusions?

Risks to Discuss with Patients Regarding Blood Transfusions

Patients must be informed that transfusion-associated circulatory overload (TACO) is now the leading cause of transfusion-related death and serious complications, occurring in 1-8% of transfusions, followed by transfusion-related acute lung injury (TRALI), infectious risks, and allergic reactions. 1

Critical Life-Threatening Risks

Transfusion-Associated Circulatory Overload (TACO)

• TACO is the #1 cause of transfusion mortality and major morbidity 1
• Occurs in 1-8% of all transfused patients 1
• Presents as acute respiratory distress, pulmonary edema, rapid heart rate, and high blood pressure during or within 12 hours of transfusion 1
• Highest risk patients: those over 70 years old, heart failure, kidney failure, low albumin, low body weight, or receiving rapid transfusion 1

Transfusion-Related Acute Lung Injury (TRALI)

• Occurs at 8.1 per 100,000 transfused blood components 1
• Develops within 6 hours of transfusion with severe breathing difficulty, low oxygen, and lung infiltrates without fluid overload 1, 2
• Critical distinction: Unlike TACO, diuretics are harmful in TRALI and should never be given 2, 1
• Fresh frozen plasma and platelets are the products most frequently implicated 2

Fatal Hemolytic Reactions

• Occurs at approximately 8 per 10 million red blood cell units 1
• Results primarily from human error and ABO incompatibility 1
• This is why strict patient identification is paramount before every transfusion 3

Common Non-Life-Threatening Reactions

Febrile Non-Hemolytic Reactions

• Occur in 1.1-2.15% of transfusions depending on leukoreduction timing 1
• Managed with paracetamol alone 1

Allergic Reactions

• Increasingly reported, particularly with plasma and platelet products 1
• Managed with antihistamines for mild reactions 1
• Avoid indiscriminate steroid use 1

Infectious Risks

Despite dramatic improvements in blood screening since 1984, infectious transmission remains a concern 4:

• HIV: 6.8 per 10 million components 1
• Hepatitis C: 8.7 per 10 million components 1
• Hepatitis B: 28-36 per 10 million components 1
• Bacterial contamination risk is increasing as a concern 5

Immunologic Complications

Alloimmunization

• Occurs in 7-30% of patients with sickle cell disease 4, 1
• Can lead to delayed hemolytic reactions, difficulty finding compatible blood, and potentially life-threatening hyperhemolysis 1
• Standard ABO/RhD matching alone does NOT eliminate this risk 1
• Particularly problematic in patients requiring repeated transfusions 4

Transfusion-Associated Immunomodulation (TRIM)

• Increases risk of multi-organ failure and infection in critically ill patients 1
• May increase risk of cancer recurrence 4

Special Population Risks

Patients with Sickle Cell Disease

• Extremely high alloimmunization rate (7-30%) due to inflammatory state and donor-recipient mismatch 4
• Risk of hyperviscosity and increased sickling from over-transfusion 4
• Hyperhaemolysis syndrome is a life-threatening complication 4
• Benefits include increased oxygen carrying capacity and reduced vaso-occlusion risk 4

Cancer Patients Receiving Chemotherapy

• Increased risks of venous thromboembolism (OR 1.60), arterial thromboembolism (OR 1.53), and mortality (OR 1.34) associated with transfusions 4
• Iron overload can occur with frequent transfusions over several years 4

Monitoring Requirements to Detect Complications

All transfusions require systematic vital sign monitoring 1:

• Minimum: before transfusion, 15 minutes after start, and within 60 minutes of completion 4, 3
• Monitor: heart rate, blood pressure, temperature, and especially respiratory rate 4, 1
• Respiratory rate is critical as dyspnea and rapid breathing are early symptoms of serious reactions 1

When to Stop Transfusion Immediately

Stop the transfusion and contact the laboratory immediately if any of these develop 4:

• Rapid heart rate
• Rash
• Breathlessness
• Low blood pressure
• Fever

Risk Mitigation Strategies

Prevention Measures

• Positive patient identification is paramount to prevent ABO incompatibility 3
• Body weight-based dosing of red blood cells 3, 1
• Slow transfusion rates in high-risk patients 3, 1
• Consider prophylactic diuretics in high-risk patients for TACO 3, 1
• Blood banks now preferentially use male-only plasma donors to reduce TRALI risk 2

Documentation Requirements

• Review previous transfusion history, drug-induced coagulopathy, congenital bleeding disorders, and thrombotic events 3
• Verify four core identifiers on compatibility label with patient identification immediately before transfusion 3