British journal of haematology
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Thromboelastography (TEG) was first described by Hartert in 1948, and was designed to monitor viscoelastic clot strength in whole blood in real time. The current TEG method and Rotational Thromboelastometry (ROTEM) were subsequently developed from the original principles. Both of the modern methods provide data by measuring changes in the viscoelastic strength of a small sample of clotting blood in response to a constant rotational force. ⋯ These TEG/ROTEM analyses therefore enable evaluation of global clotting function and the monitoring of haemostatic treatment in various clinical situations, not only in patients with genetic bleeding disorders, such as haemophilia, but also in patients undergoing cardiac surgery, liver transplantation or suffering from traumatic injury. Some evidence suggests that haemostatic management using TEG/ROTEM leads to a reduction in total transfusions of whole blood or clotting factors. Wider clinical application of this technology seems likely.
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Hellmut Hartert was the first person to exploit the viscoelastic properties of clotting blood to measure blood coagulation in 1948. Since then, the technology has improved, allowing these analyses to be performed as point-of-care tests with immediately-available results. The addition of several activators and inhibitors to the original assay creates a panel of tests able to quantify the different aspects of blood clotting that can rival conventional laboratory assays. ⋯ Viscoelastic analyses of blood coagulation are mainly used to guide haemostatic therapy in bleeding patients and have proven superior to standard clotting tests in some circumstances. There is potential to extend their use to other areas, such as drug monitoring, and diagnosis and management of congenital bleeding disorders. The forthcoming cartridge-based assays are expected to improve the reliability and usability of viscoelastic assays of blood coagulation but high quality clinical trials remain urgently needed to determine their exact place, benefit and cost effectiveness.
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Direct oral anticoagulants (DOACs), including the direct thrombin inhibitor, dabigatran, and the direct factor Xa (FXa) inhibitors, rivaroxaban, apixaban and edoxaban, are approved for thromboembolism prevention and treatment. These drugs do not require routine coagulation monitoring but, in some circumstances, measurement of drug level or anticoagulant effect may be necessary. Although traditional coagulation tests lack analytical sensitivity and specificity, they are widely available and inexpensive, and can provide useful information regarding the residual anticoagulant effect of DOACs. Hemoclot® and ecarin-based assays can be used to quantify dabigatran level and calibrated chromogenic anti-FXa assays are suitable for measuring rivaroxaban, apixaban and edoxaban levels, but these tests are not yet widely available.
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The field of adoptive cell transfer includes chimeric antigen receptor (CAR) engineered T cells, constructs that emerged from basic research into principles of immunology and have transformed into clinically effective therapies for haematological malignancies. T cells engineered to express these artificial receptors hold great promise, but also carry significant risk. While permanent genetic modification of mature T cells appears safe, modulating their in vivo function is difficult, partly because the robust response can trigger other arms of the immune system. ⋯ Currently, clinical trials in patients with relapsed or refractory B cell malignancies treated with CD19-specific CAR T cells have induced durable remissions in adults and children. Results from these trials indicate that more work needs to be done to understand biomarkers of efficacy, the role of T cell persistence and how to integrate this care into standard practice. Cell therapy will not be a 'one size fits all' class of medicine, and here we will discuss the development of this therapy and important questions for its future.
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Following a recent court judgment, legal and moral issues surrounding consent have been thrown into the spotlight. Elizabeth Larner, Solicitor, and Rachel Carter, Partner, of Wollen Michelmore LLP, look at the issues surrounding consent, including where problems arise in the fields of clinical negligence and non-accidental injury and what health care professionals can do to ensure that their advice to a patient about a procedure or treatment is sufficiently cogent and appropriately recorded so as to avoid later criticism and possible legal action. This annotation gives an overview of the legal principles surrounding consent in medical practice including informed consent, refusal of treatment and issues of capacity.