Risk of Infection and Blood Transfusion in Trauma

To the Editor:

We would like to thank Drs. Joob and Wiwanitkit for their observations on our article. We agree that blood transfusion should be used sparingly, but that it is ultimately unavoidable in many trauma patients. The concept of this article, however, was not to reduce blood transfusion per se. Rather, our previous studies showing fundamental differences in compensatory response to blunt and penetrating trauma is what sparked this research question on blood transfusions and infection risk.

As in any retrospective study, we agree that there are confounding factors. As you mention, the confounding factors of local sanitation and safety practice of the local blood bank are not applicable in highly regulated centers in the United States. The local blood bank is fully accredited and meets or exceeds national and international safety and quality standards. The hospital likewise is highly regulated and accredited by both private and governmental agencies.

In terms of the quantity transfused, this issue was addressed in Figure 1; patients with penetrating trauma received significantly more blood products (in addition to having a higher overall transfusion rate). Despite this, transfusion in patients with penetrating trauma did not independently predict infection, while in patients with blunt trauma (who received tranfusions with fewer blood products), it did. Thus, it is unlikely that transfusion amount would confound these results. Within the context of the limitations discussed in the article, we are confident in our conclusion that the mechanism of injury, blunt versus penetrating, influences the infection risk from early transfusion.

We thank you again for your comments.

Charles A. Karcutskie

Nicholas Namias