Antithrombin (AT) has been used for over 25 years to successfully treat disseminated intravascular coagulation (DIC). A four-day AT therapy in patients with DIC in the KyberSept trial has been related to a clear survival benefit in patients not receiving concomitant heparin. Gonano and coworkers performed thrombelastography (TEG) measurements in patients with severe sepsis and clearly showed hypercoagulability, as defined by five TEG parameters, compared to healthy controls. In the AT group they found a trend towards normalization of TEG parameters after treatment, although this did not reach statistical significance. This first clinical evaluation of hypercoagulability during AT treatment could not provide evidence for an attenuation of coagulopathy, an effect that might be due to high inter-individual variability.