Surgery and invasive procedures in patients on long-term treatment with direct oral anticoagulants: Thrombin or factor-Xa inhibitors. Recommendations of the Working Group on perioperative haemostasis and the French Study Group on thrombosis and haemostasis

Impact of apixaban on routine and specific coagulation assays: a practical laboratory guide

Apixaban does not require monitoring nor frequent dose adjustment. However, searching for the optimal dose for the individual patient may be useful in some situations. Moreover, there is a need for clinicians to know whether coagulation assays are influenced by apixaban use. The aim of this study was to determine which coagulation assay could be used to assess the impact of apixaban on haemostasis and provide good laboratory recommendations for the accurate interpretation of haemostasis assays. Apixaban is spiked at concentrations ranging from 5 to 500 ng/mlin platelet-poor plasma. Routinely used or more specific coagulation assays are tested. Results show a concentration dependent prolongation of aPTT, PT and dilute PT. The sensitivity mainly depends on the reagent, but none of these tests is sensitive enough to ensure an accurate estimation of the pharmacodynamic effect of apixaban. FXa chromogenic assays show high sensitivity and a linear correlation depending on the reagent and/or the methodology. Immunological assays and assays acting below the FXa are not influenced by apixaban. In conclusion, PT and/or dilute PT cannot be used to assess apixaban pharmacodynamic properties. More specific and sensitive assays such as chromogenic FXa assays using specific calibrators are required. In case of thrombophilia or in the exploration of a haemorrhagic event, immunological assays should be recommended, when applicable. Standardisation of the time between the last intake of apixaban and the sampling is mandatory.

Managing New Oral Anticoagulants in the Perioperative and Intensive Care Unit Setting

Managing patients in the perioperative setting receiving novel oral anticoagulation agents for thromboprophylaxis or stroke prevention with atrial fibrillation is an important consideration for clinicians. The novel oral anticoagulation agents include direct Factor Xa inhibitors rivaroxaban and apixaban, and the direct thrombin inhibitor dabigatran. In elective surgery, discontinuing their use is important, but renal function must also be considered because elimination is highly dependent on renal elimination. If bleeding occurs in patients who have received these agents, common principles of bleeding management as with any anticoagulant (including the known principles for warfarin) should be considered. This review summarizes the available data regarding the management of bleeding with novel oral anticoagulation agents. Hemodialysis is a therapeutic option for dabigatran-related bleeding, while in vitro studies showed that prothrombin complex concentrates are reported to be useful for rivaroxaban-related bleeding. Additional clinical studies are needed to determine the best method for reversal of the novel oral anticoagulation agents when bleeding occurs.

Improving the use of direct oral anticoagulants in atrial fibrillation

The need for anticoagulation in patients with atrial fibrillation (AF), and the inherent limitations of warfarin have fostered the search for direct oral anticoagulant drugs (DOACs). In recent years, inhibitors of thrombin (Dabigatran etexilate) and of activated factor X (Rivaroxaban, Apixaban) have become clinically available, and current guidelines of the European Society of Cardiology recommend their use in AF patients. However, limitations and uncertainties as to their clinical handling have emerged. With the exception of those on Dabigatran, caution is presently recommended in patients undergoing ablation for AF, and in those who need dual antiplatelet treatment and/or invasive procedures. The use of DOACs is precluded in patients with (mechanical) heart valves, severe kidney or liver failure, malignancy, in those on prasugrel or ticagrelor, in those with the need for coronary stenting, and in naive patients with AF who need cardioversion. Moreover it must be borne in mind that limited long-term efficacy and safety data are available and that adherence of patients to DOACs may be a major issue in the real-life setting. The definition and type of monitoring to be employed to evaluate adherence to DOACs is lacking, nor have we practical guidelines on how to handle bleeding in patients on DOACs. Finally, ad hoc validated definitions of therapeutic failures are crucial in cost/utility analyses, but these are not available for DOACs. Thus, caution, vigilance and further clinical data are mandatory for a safe and appropriate use of DOACs as alternatives to warfarin in AF patients in real-life clinical settings.

Incidence of neuraxial haematoma after total hip or knee surgery: RECORD programme (rivaroxaban vs. enoxaparin)

BACKGROUND

Patients receiving anticoagulants could be at higher risk of compressive haematoma with neuraxial anaesthesia use. The phase III RECORD programme compared rivaroxaban with enoxaparin for prevention of venous thromboembolism after total hip or knee replacement surgery in more than 12,500 patients. This observational analysis evaluated the risk of neuraxial haematoma after neuraxial anaesthesia in patients receiving rivaroxaban or enoxaparin using pooled RECORD1-4 data.

METHODS

The incidences of intraspinal bleeding or haemorrhagic puncture were recorded as part of the criteria for major bleeding (the primary safety outcome in the RECORD studies). Incidences of allogeneic transfusion and venous thromboembolism by type of anaesthesia were also recorded.

RESULTS

No compressive haematomas occurred in rivaroxaban-treated patients (10 mg once daily started 6-8 h after surgery) who underwent neuraxial anaesthesia (n = 4086). Among enoxaparin-treated patients (n = 4090), one compressive spinal haematoma requiring laminectomy occurred after epidural catheter removal in an elderly female patient with renal insufficiency undergoing total knee replacement. Total venous thromboembolism rates did not differ according to type of anaesthesia.

CONCLUSION

Although no issues were observed with the use of neuraxial anaesthesia in this population of 4086 patients receiving rivaroxaban after total hip or knee replacement, it is important to remain aware of the risk of compressive haematoma. This may be of particular concern in elderly patients with renal insufficiency receiving an anticoagulant predominantly eliminated via the kidneys.

EHRA practical guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation: executive summary

New oral anticoagulants (NOACs) are an alternative for vitamin K antagonists (VKAs) to prevent stroke in patients with non-valvular atrial fibrillation (AF). Both physicians and patients will have to learn how to use these drugs effectively and safely in specific clinical situations. This text is an executive summary of a practical guide that the European Heart Rhythm Association (EHRA) has assembled to help physicians in the use of the different NOACs. The full text is being published in EP Europace. Practical answers have been formulated for 15 concrete clinical scenarios: (i) practical start-up and follow-up scheme for patients on NOACs; (ii) how to measure the anticoagulant effect of NOACs; (iii) drug-drug interactions and pharmacokinetics of NOACs; (iv) switching between anticoagulant regimens; (v) ensuring compliance of NOAC intake; (vi) how to deal with dosing errors; (vii) patients with chronic kidney disease; (viii) what to do if there is a (suspected) overdose without bleeding, or a clotting test is indicating a risk of bleeding?; (ix) management of bleeding complications; (x) patients undergoing a planned surgical intervention or ablation; (xi) patients undergoing an urgent surgical intervention; (xii) patients with AF and coronary artery disease; (xiii) cardioversion in a NOAC-treated patient; (xiv) patients presenting with acute stroke while on NOACs; (xv) NOACs vs. VKAs in AF patients with a malignancy. Since new information is becoming available at a rapid pace, an EHRA web site with the latest updated information accompanies the guide (www.NOACforAF.eu). It also contains links to the ESC AF Guidelines, a key message pocket booklet, print-ready files for a proposed universal NOAC anticoagulation card, and feedback possibilities.

Management of intracerebral hemorrhage in the presence of anticoagulant therapy

Intracerebral hemorrhage (ICH) represents a potentially lethal form of stroke. ICH in a patient taking anticoagulant therapy presents unique diagnostic and therapeutic challenges. Specific clinical circumstances, outcomes, and evidence-based or rationally derived treatments (when the evidence is incomplete) are reviewed.

Antithrombotic agents and invasive procedures--hematologist point of view

The management of a patient treated with an antithrombotic agent who requires an invasive procedure remains challenging. There are antidotes neither for the antiplatelet agents nor the new anticoagulants. A good knowledge of basic pharmacology of these drugs and the help of a hematologist within a multidisciplinary approach are essential. The potential interest of laboratory tests and the use of reversal agents, and the transfusion of plasma and platelets will be discussed.

New direct oral anticoagulants--current therapeutic options and treatment recommendations for bleeding complications

To date, clinical studies show that the incidence of spontaneous bleeding with new direct oral anticoagulants (DOAs) is comparable to that of established anticoagulants. However, unlike vitamin K antagonists, there are currently no clinically available antidotes or approved reversal agents for new DOAs. Restoring normal coagulation is important in many cases, such as emergency surgeries, serious bleedings, or anticoagulant overdosing. Attempts have been made to restore normal coagulation after treatment with new DOAs using compounds such as recombinant activated factor VII (rFVIIa), prothrombin complex concentrate (PCC), or FEIBA (factor eight inhibitor bypassing activity). Limited pre-clinical data and even less clinical evidence are available on the usefulness of these methods in restoring normal coagulation for the emergency management of critical bleeding episodes. Evaluating the utility of DOAs is further complicated by the fact that it is unknown how predictive established test systems are of the bleeding risks. Clinical practice requires further evaluation of the emergency management options for the new DOAs to define the agents and the doses that are most useful. Furthermore, patients receiving long-term treatment with a DOA are likely to undergo elective surgery at some point, and there is lack of evidence regarding perioperative treatment regimens under such conditions. This review summarises potential bleeding management options and available data on the new DOAs.