What is the management of Transfusion-Related Acute Lung Injury (TRALI)?

Management of Transfusion-Related Acute Lung Injury (TRALI)

TRALI management requires immediate cessation of transfusion, supportive respiratory care, and hemodynamic support, as this life-threatening complication presents with acute hypoxemia and non-cardiogenic pulmonary edema during or shortly after blood transfusion. 1, 2

Definition and Clinical Presentation

• TRALI is defined as a clinical syndrome that presents with acute hypoxemia and non-cardiogenic pulmonary edema during or after blood transfusion 1
• Symptoms typically appear within 1-2 hours after transfusion and include hypoxemia, fever, dyspnea, and bilateral pulmonary infiltrates 2, 3
• TRALI must be differentiated from Transfusion-Associated Circulatory Overload (TACO), which presents with similar respiratory distress but is characterized by fluid overload and cardiovascular changes 2
• The incidence of TRALI is approximately 0.81 per 10,000 transfused blood components (8.1 per 100,000) according to recent prospective studies 1

Pathophysiology

• TRALI follows a "two-event model" similar to acute respiratory distress syndrome (ARDS) 4
• First mechanism: Donor antibodies (anti-HLA or anti-HNA) interact with recipient antigens, triggering neutrophil activation and pulmonary damage 2, 5
• Second mechanism: Bioactive lipids or other substances that accumulate during blood product storage may cause reactions in susceptible patients 5, 4
• All blood components can cause TRALI, but those with higher plasma volume carry greater risk 5

Immediate Management

• Step 1: Stop the transfusion immediately when TRALI is suspected 2, 3
• Step 2: Provide respiratory support based on severity:
  • Oxygen supplementation for mild cases 2, 3
  • Non-invasive ventilation for moderate hypoxemia 6
  • Mechanical ventilation for severe respiratory failure 3, 7
• Step 3: Hemodynamic support with fluids and vasopressors if needed for hypotension 2, 6
• Step 4: Rule out other causes of acute respiratory distress:
  • Perform chest imaging to confirm non-cardiogenic pulmonary edema 3, 7
  • Evaluate for volume overload, cardiac dysfunction, and bacterial contamination 2

Clinical Course and Prognosis

• Most patients show clinical improvement within the first few hours of supportive care 3
• Complete resolution typically occurs within 96 hours in the majority of cases 3
• Some patients may require mechanical ventilation for several days 3, 6
• Unlike TACO, diuretics are generally not indicated in TRALI as the pulmonary edema is non-cardiogenic 2

Prevention Strategies

• Report all suspected cases of TRALI to the blood bank for donor investigation 5
• Blood banks have implemented risk reduction strategies:
  • Screening donors for leukocyte antibodies 2, 5
  • Using male-only plasma donors or never-pregnant females 2, 5
  • Deferring donors implicated in previous TRALI cases 5
• Careful assessment of transfusion necessity to avoid unnecessary exposure 5

Special Considerations

• TRALI can occur in all patient populations, including neonates and immunocompromised patients 7, 6
• TRALI has been reported with intravenous immunoglobulin (IVIG) infusions, not just standard blood products 6
• TRALI remains underdiagnosed and underreported, particularly in certain populations like neonates 7
• The diagnosis is primarily clinical and made by excluding other causes of acute respiratory failure following transfusion 3, 7