FAQ's
What is the difference between classical Thromboelastography and ROTEM® ?
The ROTEM® technology avoids several limitations of traditional instruments for thrombelastography, especially the susceptibility to mechanical shocks and vibrations. Clot stability is detected simultaneously on 4- channels with an innovative shock resistant opto-mechanical detection method. The operation is very simple: Intuitive touchscreen operated software.
Can ROTEM® data be exported?
ROTEM® comes with a powerful intuitive software package and a sophisticated data handling system. The database stores all results, including the reaction curves. Data can be printed with a standard printer, transmitted to the LIS or can be easily exported into MS Excel® or other software for further processing. Moreover, ongoing measurements can be displayed (via live transmission) on another computer, e.g. in the OR
Which type of sample should be preferably used?
Preferably citrated whole blood, the same sample which is used for coagulation tests. Normal blood samples collected in sodium citrate are stable for hours. Non anticoagulated blood may be theoretically be superior, but in practice this sample is difficult to standardise and the quality of the results is storage time dependent. Clinical samples, especially during surgery or from patients with DIC, may be less stable and should be analysed quickly. Other samples for research can be plasma or even clottable plasma fractions such as fibrinogen solutions (e.g. fibrin sealants), when the appropriate activator is added.
What is the advantage of ROTEM®Analysis over classical Thromboelastography or related methods?
Non-activated classical thromboelastography with native blood is very sensitive, but time consuming. It requires very careful pre-analytical conditions in order to prevent artefacts and provides global information on haemostasis without further differentiation. A superior diagnostic power is achieved with ROTEM®Analysis. Activated tests shorten the time to results and localise the defects. Deficiencies of coagulation factors can be discriminated from effects of anticoagulants, hyperfibrinolysis, fibrin polymerisation disorders, severe platelet function defects etc. Sample handling is relatively uncritical and reliable data are also obtained during or after surgery. And handling is very easy.
What is the sensitivity for severe platelet disorders or thrombocytopenia?
Clinically severe platelet disorders induced by antibiotics or anaesthesia drugs, certain X- ray contrast media and specifically strong direct anti-platelet drugs such as abciximab, or severe thrombocytopenia are often detected with ROTEM®. Like in vivo, the clot firmness is influenced by the interaction of platelets with fibrinogen. A relatively firm clot can be generated in some cases when the fibrinogen level is adequate- in spite of thrombocytopenia.
What is the economical justification for introducing new tests?
Peri- or postoperative bleeding may lead to severe complications and very high expenses for blood products, factor concentrates or other treatment. It prolongs the time in the ICU and in the hospital in general. A specific, evidence based therapy instead of prophylactic use of blood products requires a correct diagnosis
"Use of TEM monitoring before reexploration has decreased the cost and potential risk for patients undergoing CABG surgery." Changes in transfusion therapy and reexploration rate after institution of a blood management program in cardiac surgical patients. Spiess BD et al., J Cardiothorac Vasc Anesth 1995 168-73
ROTEM® is very cost efficient when compared to other whole blood systems systems
What can be potentially saved by ROTEM®Analysis?
Factor concentrates, fresh frozen plasma, cryo precipitate, platelet concentrates
Antifibrinolytic drugs, other drugs
Surgery time and patient time in the ICU
Total time in the hospital and for recovery
Is a POC application of ROTEM® efficient, or should the laboratory perform the assays?
This depends strongly on the organisation of the individual hospital. If the turnaround time is > 30 min, POC testing may be a clear advantage. Results should be available quickly in order to support therapeutic decisions.
Provided that a sample arrives in the lab within a few minutes and immediate handling is possible, the lab may be the right place. The ongoing measurements can be displayed through live transmission on a computer in the OR.
Can I check the performance of the system?
Quality controls should be used like for any other method for in vitro diagnostic systems. A human based control is available (ROTROLTM N). This control provides a clotting pattern very similar like a whole blood sample. A batch specific table of expected values is included
Can ROTEM®Systems be used with animal blood?
ROTEM® has been successfully used with blood from various species, including small lab animals such as rats. The necessary blood volume per test is 300µl.