What are the symptoms of Transfusion-Related Acute Lung Injury (TRALI)?

Symptoms of Transfusion-Related Acute Lung Injury (TRALI)

Transfusion-Related Acute Lung Injury (TRALI) presents with hypoxemia, fever, dyspnea, and potentially fluid in the endotracheal tube, with symptoms appearing 1-2 hours after transfusion and reaching maximum intensity within 6 hours. 1, 2

Key Clinical Manifestations

• Respiratory symptoms:

  • Acute respiratory distress 1
  • Hypoxemia (decreased oxygen levels) 1, 2
  • Dyspnea (shortness of breath) 1, 2
  • Increased peak airway pressure 1
  • Fluid in the endotracheal tube (in intubated patients) 1, 2

• Systemic symptoms:

  • Fever 1
  • Hypotension 3
  • Tachycardia 3

Timing and Progression

• Signs and symptoms typically appear 1-2 hours after transfusion 1, 2
• Symptoms reach maximum intensity within 6 hours of transfusion 1
• Most patients recover within 96 hours, although TRALI remains one of the top three most common causes of transfusion-related deaths 1, 2

Radiographic Findings

• Bilateral pulmonary infiltrates on chest X-ray 4
• Radiographic appearance similar to non-cardiogenic pulmonary edema 5
• These radiographic findings develop rapidly after symptom onset 4

Differentiating from Other Transfusion Reactions

• TRALI symptoms are clinically indistinguishable from Transfusion-Associated Circulatory Overload (TACO) except for the absence of fever and presence of volume overload in TACO 1
• Unlike allergic transfusion reactions which primarily manifest with urticaria and skin symptoms, TRALI predominantly affects the respiratory system 1, 3
• Unlike bacterial contamination which primarily presents with hyperthermia and hypotension, TRALI has predominant respiratory symptoms 1, 3

Pathophysiology and Risk Factors

• TRALI is caused by donor antibodies in plasma-containing blood components interacting with antigens on the patient's granulocytes 1
• Most commonly associated with fresh frozen plasma (FFP) and platelet transfusions, though occasionally with red blood cells 2
• Neutrophils play a central role in mediating the early immune response and lung vascular injury 6

Clinical Pitfalls and Caveats

• TRALI may be underdiagnosed and underreported 7, 6
• General anesthesia may mask the symptoms of TRALI 1
• TRALI must be distinguished from transfusion-associated circulatory overload, allergic reactions, and sepsis 7
• Unlike TACO, diuretics are ineffective for TRALI management 2
• Treatment consists of stopping the transfusion and instituting critical care supportive measures 1