Many here in scandinavia use tranexamic acid in knee replecement surgery. There are no evidence of an increased risk for thromboembolic event. How effective tranexamic acid would be in reducing blood loss depends on severel things like; timing, dose and the whole hemostatic programe that you apply to your patient. In knee replecement tranexamic acid is one of some simple low cost interventions that will in total make a big impact on blood loss.