Transfusion-Related Acute Lung Injured (TRALI): Current Concepts

Transfusion-related acute lung injury (TRALI) is a life-threatening intervention that develops within 6 hours of transfusion of one or more units of blood, and is an important cause of morbidity and mortality resulting from transfusion. It is necessary to dismiss other causes of acute lung injury (ALI), like sepsis, acute cardiogenic edema, acute respiratory distress syndrome (ARDS) or bacterial infection. There are two mechanisms that lead to the development of this syndrome: immune-mediated and no immune- mediated TRALI. A common theme among the experimental TRALI models is the central importance of neutrophils in mediating the early immune response, and lung vascular injury. Central clinical symptoms are dyspnea, tachypnea, tachycardia, cyanosis and pulmonary secretions, altogether with other hemodynamic alterations, such as hypotension and fever. Complementary to these clinical findings, long-term validated animal models for TRALI should allow the determination of the cellular targets for TRALI-inducing alloantibodies as well as delineation of the underlying pathogenic molecular mechanisms, and key molecular mediators of the pathology. Diagnostic criteria have been established and preventive measures have been implemented. These actions have contributed to the reduction in the overallnumber of fatalities. However, TRALI still remains a clinical problem. Any complication suspected of TRALI should immediately be reported.