What are the recommended techniques and protocols for a safe and effective blood transfusion in patients with a history of transfusion reactions or allergies?

Blood Transfusion Techniques for Patients with Prior Reactions or Allergies

For patients with a history of transfusion reactions or allergies, immediately stop any transfusion at the first sign of symptoms, use washed blood products for those with documented allergic reactions, and implement rigorous patient identification protocols to prevent life-threatening hemolytic reactions. 1, 2

Pre-Transfusion Risk Assessment and Patient Identification

Identify high-risk patients before transfusion:

• Patients with prior allergic reactions should receive plasma-reduced or washed blood components 2, 3
• Patients with multiple food allergies (particularly carrot, celery, hazelnut, peanut) are at increased risk for allergic transfusion reactions and should be flagged 3
• Older patients (>70 years), those with heart failure, renal failure, or hypoalbuminemia are at increased risk for TACO 1
• Verify patient identification using four core identifiers (first name, last name, date of birth, patient ID number) at bedside before every transfusion 1, 4

Critical pre-transfusion steps:

• Visually inspect blood products for leakage, discoloration, clots, or clumps before administration 1
• Check compatibility label against patient identification at bedside 4
• Use electronic transfusion management systems rather than manual checking when available 1

Monitoring Protocol During Transfusion

Implement intensive monitoring, especially during the critical first 10 minutes:

• Monitor vital signs (heart rate, blood pressure, temperature, respiratory rate) at: pre-transfusion, 15 minutes after starting, at completion, and 15 minutes post-transfusion 1
• The first 10 minutes are critical—immediate reactions typically occur within the first minute 1
• Monitor continuously for the first 15 minutes, then every 15 minutes thereafter 4, 2

Watch for these warning signs requiring immediate action:

• Tachycardia (>110 beats/min), rash or urticaria, breathlessness or respiratory distress, back pain or chest tightness 1
• Hypotension, fever, hemoglobinuria, or microvascular bleeding 2
• Monitor peak airway pressure to detect potential TRALI 2

Immediate Management of Acute Reactions

If any reaction occurs, follow this algorithm:

1. Stop the transfusion immediately—do not wait to confirm the reaction type 1, 2
2. Maintain IV access with normal saline for medication administration 1, 2
3. Contact the transfusion laboratory immediately and return the blood product for investigation 4, 2
4. Administer high-flow oxygen (high FiO2) to address potential hypoxemia 1

For anaphylaxis or severe reactions:

• Administer epinephrine 0.3 mg IM into anterolateral mid-thigh; may repeat once 1
• Call emergency services or resuscitation team 1
• Recline patient flat if hypotensive 1
• Administer normal saline bolus 1000-2000 mL 1

For moderate allergic reactions:

• Antihistamines for urticaria or mild allergic symptoms 2
• Consider hydrocortisone 100-500 mg IV and famotidine 20 mg IV 1

Laboratory Workup for Suspected Reactions

Send these labs immediately:

• Complete blood count, PT, aPTT, Clauss fibrinogen 1
• Direct antiglobulin test (DAT/Coombs test) 1
• Repeat cross-match 1
• Visual inspection of plasma for hemolysis 1

Prevention Strategies for Future Transfusions

For patients with documented allergic reactions:

• Use washed blood products (plasma-reduced or washed platelet concentrates) for future transfusions 2, 3
• Consider virus-inactivated frozen pooled plasma as an alternative 3
• Do NOT routinely use acetaminophen or diphenhydramine premedication—these have failed to prevent transfusion reactions in studies and may mask early warning signs 5, 6

For patients at risk of TACO:

• Use slower transfusion rates 2
• Implement weight-based dosing of blood products 2
• Transfuse single units in non-hemorrhaging patients and reassess before giving additional units 1
• Consider diuretic therapy for future transfusions 1

For patients requiring multiple transfusions (e.g., sickle cell disease):

• Obtain extended red cell antigen profile (genotype preferred over phenotype) 4
• Use extended antigen matching (C/c, E/e, K, Jka/Jkb, Fya/Fyb, S/s) for all future transfusions 4

Special Considerations for High-Risk Scenarios

When compatible blood is unavailable in life-threatening situations:

• ABO compatibility takes absolute priority—never transfuse ABO-incompatible blood as this causes immediate, severe hemolysis with high mortality 4
• Consider prophylactic immunosuppression (IVIg 0.4-1 g/kg/day for 3-5 days, methylprednisolone 1-4 mg/kg/day, or rituximab) before transfusion in high-risk patients 4
• Consider automated or manual red cell exchange instead of simple transfusion when feasible 4

To minimize TRALI risk:

• Blood banks should use male-only plasma donors, particularly avoiding multiparous women who have higher frequencies of anti-HLA and anti-HNA antibodies 1
• Fresh frozen plasma and apheresis platelets carry the highest TRALI risk 1
• Consider prothrombin complex concentrate (PCC) over FFP when rapid factor replacement is needed, as PCC is NOT associated with TRALI 1

Documentation and Reporting Requirements

Complete these essential steps:

• Document all transfusions in patient record—100% traceability is a legal requirement 1
• Notify the patient's general practitioner to remove them from the donor pool 1
• Report to the blood bank, as TRALI and other serious reactions are underdiagnosed and underreported 1
• Inform patients they received blood products before discharge 1
• Document shared decision-making discussions with patient/family regarding transfusion risks 4

Common Pitfalls to Avoid

Be aware of these diagnostic challenges:

• General anesthesia may mask symptoms of both hemolytic and nonhemolytic transfusion reactions 2
• Diagnosis during ongoing hemorrhage may be difficult 2
• Bacterial contamination can present with similar symptoms to TACO and TRALI 1
• Most non-severe allergic reactions (75% of cases) resolve with treatment and could allow transfusion completion—stopping unnecessarily wastes blood products 7
• However, when in doubt, always stop the transfusion first 1, 2