Six hours after receiving pooled platelets, a ventilated post-operative patient develops acute hypoxaemia with bilateral infiltrates on chest radiograph and PaO2/FiO2 of 180 mmHg. Echocardiography shows normal left atrial pressure. The most likely mechanism is:

• A Donor anti-HLA antibodies attacking recipient pulmonary endothelium ✓
• B Volume overload from the plasma content of the product
• C Transfusion of ABO-incompatible platelets causing complement activation
• D Febrile reaction to cytokines accumulated during storage

Explanation

This is transfusion-related acute lung injury (TRALI): new-onset hypoxaemia with bilateral infiltrates within six hours of transfusion and no hydrostatic cause. The dominant mechanism is passively transferred donor antibodies against recipient HLA or neutrophil antigens causing capillary leak. Option B describes TACO, which shows elevated left-sided filling pressures, and option D describes a simple febrile non-haemolytic reaction without lung injury.

Reference: Bailey and Love's Short Practice of Surgery, 28th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.