Transfusion as a Risk Factor for ALI and ARDS

Conclusion

The last several years have seen an accumulation of evidence that TRALI is an important complication of blood transfusion and is likely occurring much more frequently than previously estimated. Most data support a causal relationship though there are admittedly confounders given the prevalence of this disorder in patients with other predispositions to ALI/ARDS, including sepsis, shock, trauma and aspiration. Both massive and submassive transfusion have been implicated as risk factors. It is apparent from the studies to date that each additional unit likely increases a patient’s risk in an additive fashion thus mitigating any false reassurances if no reaction is witnessed after the first few units are transfused.

The implications of this disorder are far and wide given the regular and wide-spread use of blood transfusions around the world. While most attention in the past has focused on the risk of transmitting infectious diseases, it is imperative that some of the light now be shifted to better defining and understanding the true prevalence of TRALI. The moral, ethical and financial issues of potentially preventive strategies (screening or deferral of particular donors, decrease in storage time and pre-storage leukoreduction) are substantial.