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Rotational thromboelastometry (ROTEM) is a point-of-care viscoelastic method and enables to assess viscoelastic profiles of whole blood in various clinical settings. ROTEM-guided bleeding management has become an essential part of patient blood management (PBM) which is an important concept in improving patient safety. Here, ROTEM testing and hemostatic interventions should be linked by evidence-based, setting-specific algorithms adapted to the specific patient population of the hospitals and the local availability of hemostatic interventions. Accordingly, ROTEM-guided algorithms implement the concept of personalized or precision medicine in perioperative bleeding management ('theranostic' approach). ROTEM-guided PBM has been shown to be effective in reducing bleeding, transfusion requirements, complication rates, and health care costs. Accordingly, several randomized-controlled trials, meta-analyses, and health technology assessments provided evidence that using ROTEM-guided algorithms in bleeding patients resulted in improved patient's safety and outcomes including perioperative morbidity and mortality. However, the implementation of ROTEM in the PBM concept requires adequate technical and interpretation training, education and logistics, as well as interdisciplinary communication and collaboration.

The incidence of bleeding and thrombo-embolic complications in patients undergoing mechanical circulatory support therapy remains high and is associated with bad outcomes and increased costs. The need for anticoagulation and anti-platelet therapy varies widely between different pulsatile and non-pulsatile ventricular-assist devices (VADs) and extracorporeal membrane oxygenation (ECMO) systems. Therefore, a unique anticoagulation protocol cannot be recommended. Notably, most thrombo-embolic complications occur despite values of conventional coagulation tests being within the targeted range. This is due to the fact that conventional coagulation tests such as international normalised ratio (INR), activated partial thromboplastin time (aPTT) and platelet count cannot detect hyper- or hypofibrinolysis, hypercoagulability due to tissue factor expression on circulating cells or increased clot firmness, and platelet aggregation as well as response to anti-platelet drugs. By contrast, point-of-care (POC) whole blood viscoelastic tests (thromboelastometry/-graphy) and platelet function tests (impedance or turbidimetric aggregometry) reflect in detail the haemostatic status of patients undergoing mechanical circulatory support therapy and the efficacy of their anticoagulation and antiaggregation therapy. Therefore, monitoring of haemostasis using POC thromboelastometry/-graphy and platelet function analysis is recommended during mechanical circulatory support therapy to reduce the risk of bleeding and thrombo-embolic complications. Notably, these haemostatic tests should be performed repeatedly during mechanical circulatory support therapy since thrombin generation, clot firmness and platelet response may change significantly over time with a high inter- and intra-individual variability. Furthermore, coagulation management can be hampered in non-pulsatile VADs by acquired von Willebrand syndrome, and in general by acquired factor XIII deficiency as well as by heparin-induced thrombocytopenia. In addition, POC testing can be used in bleeding patients to guide calculated goal-directed therapy with allogeneic blood products, haemostatic drugs and coagulation factor concentrates to optimise the haemostasis and to minimise transfusion requirements, transfusion-associated adverse events and to avoid thrombo-embolic complications, as well. However, coagulation management in patients undergoing mechanical circulatory support therapy is somehow like navigating between Scylla and Charybdis, and development of protocols based on POC testing seems to be beneficial., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Background: More and more patients are treated with antiplatelet drugs today. In this context a sufficient inhibition of platelet aggregation, on the one hand, is of essential importance to the efficiency of prophylaxis of myocardial and cerebral infarction and to avoiding thrombosis of drug-eluting stents. On the other hand, this medication can result in an increased risk of perioperative bleeding. In both situations control of the efficiency of therapy or rather the assessment of the impairment of hemostasis is of vital importance., Methods: Platelet function analyzer (PFA-100), multiple platelet function analyzer (Multiplate), and rotational thrombelastometry (ROTEM) are reliable and easy to use point-of-care (POC) devices. Since these three analyzers monitor different aspects of platelet function and have different limitations, the selection of the right test system depends on the right question., Results: PFA-100 enables a sensitive detection of von Willebrand's syndrome. Multiplate is apt to control efficiency of platelet inhibiton with acetylsalicylic acid, clopidogrel and glycoprotein IIb/IIIa receptor antagonists. ROTEM analysis offers the opportunity to assess hemostasis as a holistic system. Thereby, ROTEM analysis particularly detects hyperfibrinolysis, heparin effects, and fibrinogen-platelet interaction., Conclusion: Due to their easy handling the described POC devices are applicable to perioperative coagulation management as well as during and after coronary intervention or to monitoring of platelet function in cardiologic practice. They enable a quick assessment of platelet function and an individually guided therapy.

Background: Perioperative bleeding remains a major challenge in liver transplantation. We aimed to compare standard laboratory tests with thromboelastometry (ROTEM ® ) with regard to their ability to predict postoperative non-surgical bleeding.Methods: Data from 243 adult liver transplant recipients from January 2012 to May 2014 were evaluated retrospectively. Upon admission to the intensive care unit, coagulation status was assessed using standard laboratory tests [prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen concentration, and platelet count] and ROTEM ® whole blood coagulation assays. Bleeding was defined as transfusion of ≥ 3 units of red blood cells or reoperation for non-surgical bleeding within 48 h after transplantation. Coagulation test results were analysed using receiver operating characteristics (ROC) in order to identify variables predictive of postoperative bleeding. Coagulation management was based on ROTEM ® -guided factor concentrate treatment.Results: The overall incidence of bleeding was 12.3% ( n =30). Twenty-three (9.5%) patients underwent reoperation and seven (2.9%) received ≥3 units of red blood cells and non-operative management. Standard laboratory tests predictive of postoperative bleeding were aPTT and PT [area under the ROC curve (AUC) 0.688 and 0.623, respectively]. Tests predictive of bleeding with ROTEM ® were CT EXTEM , CFT INTEM , A10 FIBTEM , and MCF FIBTEM , with AUCs of 0.682, 0.615, 0.615, and 0.611, respectively. Fibrinogen concentration, platelet count, and other ROTEM ® variables failed to demonstrate predictive value for postoperative bleeding (AUC <0.6). Dialysis-dependent kidney failure, 30 day mortality, and median model for endstage liver disease score were all significantly higher in bleeding patients.Conclusions: Although both postoperative standard laboratory tests and ROTEM ® assays could identify patients at risk for postoperative bleeding, ROTEM ® assays demonstrated a greater predictive value for impaired fibrinogen polymerization-related coagulopathy. [ABSTRACT FROM AUTHOR]

Impaired platelet function is a major risk factor for peri-operative bleeding and transfusion. This prospective, observational study enrolled 101 consecutive patients undergoing elective cardiac surgery with cardiopulmonary bypass. Platelet function was assessed by two whole blood impedance aggregometers (ROTEM(®) platelet and Multiplate(®) ), using three different activators (arachidonic acid, adenosine diphosphate and thrombin receptor-activating peptide-6), at three peri-operative time points (before anaesthesia, after aortic declamping and 5-10 min after protamine administration). Platelet function was impaired over the time-course in all assays. Results after protamine administration demonstrated the best correlation with postoperative chest tube drainage. Patients with a chest tube drainage exceeding the 75th percentile of the entire study population, during the first 24 postoperative hours, were characterised to have excessive bleeding. Both devices provided similar predictability for postoperative chest tube drainage and red blood cell transfusion requirements. The latter was associated with the degree of platelet inhibition and the number of pathways inhibited determined respective cut-off values. [ABSTRACT FROM AUTHOR]