 Brain parenchyma express tissue factor and other coagulation factors in high concentrations. In addition, neuro critical patients NCP may present platelet dysfunction, hyperfibrinolysis, hypo coagulation and or hyper coagulation status, early after the injury. It is not known whether these alterations of hemostasis are due to a specific brain response to aggression, or they are included into a systemic response. This prospective, observational study is aimed to investigate the coagulation disorders specifically associated with cerebral aggression. 