What are the signs of a transfusion reaction and what actions should be taken if they occur?

Signs of Transfusion Reactions and When to Stop

Stop the transfusion immediately at the first sign of ANY suspected transfusion reaction—this is the single most critical intervention that can prevent progression to severe morbidity or mortality. 1

Critical Signs Requiring Immediate Transfusion Cessation

High-Risk Clinical Triad (Within 10 Minutes)

The most dangerous presentation is the triad of:

• Pain at the IV site
• Difficulty breathing
• Fever

This combination occurring within 10 minutes of blood transfusion indicates an acute hemolytic transfusion reaction, which is a medical emergency. 2 The mortality risk is approximately 1:1,250,000 RBC units transfused, but immediate action is essential. 2

Other Signs Requiring Immediate Stoppage

Cardiovascular/Hemodynamic Signs:

• Tachycardia (>110 beats/min) 1
• Hypotension or hemodynamic instability 3
• Chest tightness 1

Respiratory Signs:

• Breathlessness or respiratory distress 1
• Dyspnea 1
• Hypoxemia 1

Dermatologic Signs:

• Rash or urticaria 1
• Pruritus and skin flushing 2

Other Warning Signs:

• Back pain 1
• Fever (isolated or with other symptoms) 3
• Oliguria or dark urine 3

Immediate Management Algorithm

Step 1: Stop and Secure (First 60 Seconds)

• Stop the transfusion immediately—do not wait to confirm the reaction type 1
• Maintain IV access with normal saline (do not remove the line) 2, 1
• Keep the blood component bag and administration set for laboratory analysis 2, 3

Step 2: Assess and Stabilize (First 5 Minutes)

• Monitor vital signs every 5-15 minutes: heart rate, blood pressure, temperature, respiratory rate, oxygen saturation 2, 1
• Administer high-flow oxygen (high FiO2) 1
• Maintain mean arterial pressure >65-70 mmHg with IV fluid resuscitation 2
• Double-check all documentation for patient identification and blood component compatibility errors 1

Step 3: Notify and Investigate (First 15 Minutes)

• Contact the transfusion laboratory/blood bank immediately 1, 3
• Send the blood component bag with administration set back to the laboratory 2, 3
• Collect post-reaction blood samples for:
  • Complete blood count 1, 3
  • Direct antiglobulin test (Coombs test) 1, 3
  • Repeat crossmatch 1, 3
  • PT, aPTT, fibrinogen 1
  • Visual inspection of plasma for hemolysis 2, 3
  • Urine analysis for hemoglobinuria 2, 3
  • Blood cultures if bacterial contamination suspected 3

Step 4: Specific Interventions Based on Presentation

For Anaphylaxis (urticaria, bronchospasm, hypotension):

• Administer epinephrine 0.3 mg IM into anterolateral mid-thigh; may repeat once 1
• Call emergency services or resuscitation team 1
• Consider hydrocortisone 100-500 mg IV and famotidine 20 mg IV 1

For TACO (fluid overload, pulmonary edema, cardiovascular changes):

• Administer diuretic therapy 1
• Position patient upright if possible 1

For TRALI (non-cardiogenic pulmonary edema, hypoxemia):

• Provide critical care supportive measures and oxygen therapy 1
• Avoid diuretics (ineffective for TRALI) 1

For Suspected Bacterial Contamination (fever within 6 hours, especially with platelets):

• Obtain blood cultures before antibiotics 3
• Initiate broad-spectrum antibiotics immediately after cultures 3

For Hemolytic Reaction (pain, fever, dark urine, oliguria):

• Aggressive fluid resuscitation to maintain urine output >100 mL/hour 3

Critical Timing Considerations

The first 10 minutes of infusion are critical—immediate reactions typically occur within the first minute. 1 However, different reactions have different time windows:

• Acute hemolytic reaction: Within 10 minutes 2
• TACO: During or up to 12 hours after transfusion 1
• TRALI: 1-2 hours after transfusion (up to 6 hours) 1, 3
• Bacterial contamination: Within 6 hours, especially with platelets 3

Common Pitfalls to Avoid

• Never continue the transfusion despite "just fever"—general anesthesia and critical illness can mask early signs of serious reactions 3
• Never assume fever is always a benign febrile non-hemolytic reaction—bacterial contamination from platelets can present with isolated fever and is potentially fatal 3
• Never restart the transfusion before laboratory clearance, even if symptoms improve, as the reaction may worsen with continued exposure 3
• Never give diuretics for TRALI—they are ineffective and may worsen outcomes 1

Monitoring Requirements

Monitor vital signs at minimum:

• Pre-transfusion 1
• 15 minutes after starting 1
• At completion 1
• 15 minutes post-transfusion 1

The first 10 minutes require the closest observation, as immediate reactions typically occur within the first minute. 1