After the consensus definition of
transfusion-related acute lung injury (
TRALI), studies have shown that the incidence of
TRALI is high in
critically ill and injured patients. When another risk factor for
lung injury is present in these patients, the term "possible
TRALI" is used. In the past years, both animal and clinical studies have taught us that a predisposing inflammatory risk factor is frequently present in
TRALI, if not mandatory. The decline in the incidence of
TRALI after implementation of the use of male-only plasma as observed in general hospital patients is also seen in the
critically ill and injured, suggesting that
antibodies play a role in possible
TRALI. Thereby, introduction of the term "possible
TRALI" has helped us in estimating incidence rates as well as to understand risk factors for
TRALI in patient populations with a high exposure to transfusion.