Transfusion-related acute lung injury (TRALI) is an acute lung injury that occurs during or following transfusion. It is typified by dyspnea, cough, hypoxemia, and noncardiogenic pulmonary edema within 6 hours of transfusion. Meanwhile, pleural effusion is a common finding in critically ill patients and potentially reflects imbalances in vascular permeability, and hydrostatic and oncotic pressures across lung capillaries. If pleural fluid is available, an analysis may help in the differential diagnosis of TRALI.