Influence of operative trauma on factor XII and inhibitor of plasminogen activator.

A parallel decrease of factor (F) XII and a fibrinolytic inhibitor of plasminogen activation (PA inhibitor) was found in a series of 52 patients subjected to vascular surgery. It was at a maximum on days 2-4 postoperatively. The most extensive decrease was found in patients undergoing aortoiliac bypass operation. These patients had the highest blood loss and the longest operation times indicating that the changes were correlated to the magnitude of surgical procedure. The parallel decrease of F XII and the fibrinolytic inhibitor suggests an association between these two proteins in vivo.