Factor XIII is a crucial coagulation factor responsible for crosslinking fibrin monomers and incorporating fibrinolytic inhibitors within the clot. Low levels of factor XIII are often seen in patients undergoing major surgery, which may potentially impede adequate hemostasis. The authors investigated the administration of recombinant factor XIII in a randomized placebo-controlled trial in 409 patients undergoing cardiac surgery. Patients had an average 40% reduction of factor XIII after the operation, which could be corrected by factor XIII administration. However, normalization of factor XIII levels was not associated with transfusion avoidance, decreased transfusion requirements or reoperation rates.

This is a very relevant and important study with an excellent design and execution, once again illustrating that normalizing abnormal coagulation factor levels does not necessarily lead to better clinical outcomes. Factor XIII is an important protein, not only involved in coagulation but also in processes such as would healing. However, factor levels of more than 50% seem to be sufficient for these processes. More studies on the role of factor XIII administration in patients with more severe deficiencies could be important.

– Marcel Levi