Evaluation eines neuen Thrombelastographie-Verfahrens-ROTEM (Rotationsthrombelastographie)

The TEG (Thrombelastography) experiences a renaissance through the ROTEM System (Rotationthrombelastometry) as a point-of-care test for the diagnosis and management of different bleeding disorders. In this study we examined several influencing variables and the sensitivity of the method with respect to different bleeding disorders, caused by changes in the function or the count of thrombocytes or the plasmatic coagulation factors. We used the ROTEM system with the tests INTEM (additional aktivation of the intrinsic pathway), EXTEM (additional aktivation of the extrinsic pathway) and NATEM (without additional aktivation). The results were compared with those, additionally determined by other methods: the platelet count, haemoglobin concentration (Hb), haematocrit (Hct), prothrombin time (PT), aktivated partial thromboplastin time (aPTT), fibrinogen concentration, PFA-100® (Platelet Funktion Analyzer 100®, a modified in-vitro bleedung test), VCP (“Virtual Capillary Prototype”, another modified in-vitro bleeding test), aggregometry and coagulometry. Particularly we examined the time interval between blood draw and the beginning of the measurement; two different pipeting methods; two different EXTEM reagents; the influence of haemodilution. Furthermore we examined bloodsamples from people, threated with ASS, phenprocoumon, heparin or suffering from thrombocytopenia or von Willebrand Syndrom. Considerable progress has been achieved in the standardization of ROTEM by altering the technique, method and reagents. It fulfils many of the criteria for a point-of-care test. ROTEM cannot replace the laboratory tests. It can only be a complement to them because it can not reveal the most common haemostasis disorders with an adequate degree of certainty. However, ROTEM is a good and sensitive method for the examination of bleeding disorders, developing perioperativly or posttraumatically, like severe blood dilution or hyperfibrinolysis (not examined in this assay) . By means of ROTEM, quick and important decisions could be made concerning the therapy in these cases. Standards for working with ROTEM have to be established and followed, since there are many variables, influencing the method, which can lead to incorrect results.