This thesis describes an ovine model of complex trauma and haemorrhage that demonstrates coagulation changes using both traditional plasma based assays and point of care viscoelastic assays that are consistent with current definitions of ATC. The degree of coagulopathy was correlated with the degree of shock as quantified by arterial lactate.Coagulopathy was also associated with activation of the protein C pathway and shedding of the endothelial glycocalyx. Fibrinolysis did not make a significant contribution to the coagulopathy observed and there was no evidence of altered platelet function in this model.ii