In 36 patients the changes of the haemostasis in relation to hypovolaemic shock period were studied after polytrauma and or surgical operations. It was shown that a correlation between the hypovolaemic shock period and the degree of haemostatic disorder exists. The significance of this interaction for the manifestation of the fat embolism syndrome was demonstrated in two casuistics. It is concluded that the haemostatic disorder in shock enhances the development of the fat embolism syndrome. As a therapeutic consequence adequate volume substitution beside specific anticoagulation seems to be of utmost importance in the posttraumatic treatment.