From the Guidelines
ROTEM (Rotational Thromboelastometry) is a crucial point-of-care blood test for evaluating viscoelastic properties of blood during clot formation and dissolution, particularly in acute bleeding situations like postpartum hemorrhage, as evidenced by a systematic review in the Journal of Thrombosis and Haemostasis 1. ROTEM provides real-time assessment of coagulation function by measuring how blood clots form, strengthen, and eventually break down, using a rotating pin immersed in a blood sample to detect changes in clot strength. The test is valuable in identifying specific coagulation defects, such as fibrinogen deficiency, platelet dysfunction, or hyperfibrinolysis, and guides targeted blood product administration. Some key aspects of ROTEM include:
- The FIBTEM test, which isolates the effect of fibrinogen by eliminating the contribution of platelets to clot formation, and its parameters (A5, A15, and MCF) correlate significantly with fibrinogen levels 1.
- The FIBTEM A5 is superior to the Clauss fibrinogen in predicting the need for transfusion of at least 4 units of red blood cells and 8 units of allogeneic products, bleeds > 2500 mL, duration of bleed, and stay duration in the high-dependency unit 1.
- A FIBTEM A5 cutoff of < 12 mm has been used in some postpartum hemorrhage transfusion protocols, as confirmed by two randomized controlled trials 1.
- Studies have found improvement in clinical outcomes when a ROTEM-guided transfusion strategy is used during obstetric hemorrhage, including reduction in transfusion products, incidence of cesarean hysterectomy, postoperative ICU admission, duration of postpartum hospitalization, and cost of hospitalization 1.
From the Research
Definition and Purpose of ROTEM
- Rotational thromboelastometry (ROTEM) is a viscoelastic method that provides a graphical and numerical representation of induced hemostasis in whole blood samples 2.
- The main purpose of ROTEM is to quickly assess the state of hemostasis, which is used in the management of bleeding from various causes.
- ROTEM plays a crucial role in the diagnostic and management of inherited fibrinogen disorders, as well as in the detection of fibrinolysis 3.
ROTEM Tests and Parameters
- ROTEM includes several tests, such as INTEM, EXTEM, and FIBTEM, which allow for a comprehensive evaluation of the coagulation process 2.
- The FIBTEM assay is particularly useful in assessing fibrinogen activity, and fibrinogen replacement therapy is recommended at an MCF (maximum clot firmness) of FIBTEM < 10 mm and FIBTEM A10 < 7 mm 2.
- ROTEM parameters, such as clot amplitude and lysis, are consistently associated with the diagnosis of coagulopathy, increased risk of bleeding, and prediction of mortality 4.
Clinical Applications of ROTEM
- ROTEM is used in various clinical settings, including cardiac surgery, trauma, and intensive care units, to guide hemostatic therapy and reduce the risk of postoperative bleeding 5, 4.
- ROTEM-guided bleeding management algorithms have been shown to effectively reduce the number of transfusions, healthcare costs, and complications, leading to improved patient safety and overall health 2, 5.
- ROTEM analysis can be performed during cardiopulmonary bypass, allowing anesthesiologists to anticipate the need for blood products and guide coagulation management 6.