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Grottke O, Afshari A, Ahmed A, Arnaoutoglou E, Bolliger D, Fenger-Eriksen C, von Heymann C. Clinical guideline on reversal of direct oral anticoagulants in patients with life threatening bleeding. Eur J Anaesthesiol 2024; 41:327-350. [PMID: 38567679 DOI: 10.1097/eja.0000000000001968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
BACKGROUND Anticoagulation is essential for the treatment and prevention of thromboembolic events. Current guidelines recommend direct oral anticoagulants (DOACs) over vitamin K antagonists in DOAC-eligible patients. The major complication of anticoagulation is serious or life-threatening haemorrhage, which may necessitate prompt haemostatic intervention. Reversal of DOACs may also be required for patients in need of urgent invasive procedures. This guideline from the European Society of Anaesthesiology and Intensive Care (ESAIC) aims to provide evidence-based recommendations and suggestions on how to manage patients on DOACs undergoing urgent or emergency procedures including the treatment of DOAC-induced bleeding. DESIGN A systematic literature search was performed, examining four drug comparators (dabigatran, rivaroxaban, apixaban, edoxaban) and clinical scenarios ranging from planned to emergency surgery with the outcomes of mortality, haematoma growth and thromboembolic complications. The GRADE (Grading of Recommendations, Assessment, Development and Evaluation) methodology was used to assess the methodological quality of the included studies. Consensus on the wording of the recommendations was achieved by a Delphi process. RESULTS So far, no results from prospective randomised trials comparing two active comparators (e.g. a direct reversal agent and an unspecific haemostatic agent such as prothrombin complex concentrate: PCC) have been published yet and the majority of publications were uncontrolled and observational studies. Thus, the certainty of evidence was assessed to be either low or very low (GRADE C). Thirty-five recommendations and clinical practice statements were developed. During the Delphi process, strong consensus (>90% agreement) was achieved in 97.1% of recommendations and consensus (75 to 90% agreement) in 2.9%. DISCUSSION DOAC-specific coagulation monitoring may help in patients at risk for elevated DOAC levels, whereas global coagulation tests are not recommended to exclude clinically relevant DOAC levels. In urgent clinical situations, haemostatic treatment using either the direct reversal or nonspecific haemostatic agents should be started without waiting for DOAC level monitoring. DOAC levels above 50 ng ml-1 may be considered clinically relevant necessitating haemostatic treatment before urgent or emergency procedures. Before cardiac surgery under activated factor Xa (FXa) inhibitors, the use of andexanet alfa is not recommended because of inhibition of unfractionated heparin, which is needed for extracorporeal circulation. In the situation of DOAC overdose without bleeding, no haemostatic intervention is suggested, instead measures to eliminate the DOACs should be taken. Due to the lack of published results from comparative prospective, randomised studies, the superiority of reversal treatment strategy vs. a nonspecific haemostatic treatment is unclear for most urgent and emergency procedures and bleeding. Due to the paucity of clinical data, no recommendations for the use of recombinant activated factor VII as a nonspecific haemostatic agent can be given. CONCLUSION In the clinical scenarios of DOAC intake before urgent procedures and DOAC-induced bleeding, practitioners should evaluate the risk of bleeding of the procedure and the severity of the DOAC-induced bleeding before initiating treatment. Optimal reversal strategy remains to be determined in future trials for most clinical settings.
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Affiliation(s)
- Oliver Grottke
- From the Department of Anaesthesiology, RWTH Aachen University Hospital, Pauwelsstrasse, Aachen, Germany (OG), Department of Paediatric and Obstetric Anaesthesia, Juliane Marie Centre, Rigshospitalet; & Department of Clinical Medicine, Copenhagen University, Denmark (AA), Department of Anaesthesia and Critical Care, Glenfield Hospital, University Hospitals of Leicester NHS Trust, Leicester (AA), Department of Cardiovascular Sciences, University of Leicester, Leicester, UK (AA), Department of Anaesthesiology, Larissa University Hospital, Larissa, Greece (EA), Clinic for Anaesthesia, Intermediate Care, Prehospital Emergency Medicine and Pain Therapy, University Hospital Basel, Spitalstrasse, Basel, Switzerland (DB), Department of Anaesthesiology, Aarhus University Hospital, Palle Juul-Jensens Boulevard, Aarhus, Denmark (CF-E) and Department of Anaesthesia, Intensive Care Medicine, Emergency Medicine and Pain Therapy, Vivantes Klinikum im Friedrichshain, Landsberger Allee, Berlin, Germany (CvH)
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Wienhold J, Rayatdoost F, Schöchl H, Grottke O. Antidote vs. unspecific hemostatic agents for the management of direct oral anticoagulant-related bleeding in trauma. Curr Opin Anaesthesiol 2024; 37:101-109. [PMID: 38390922 DOI: 10.1097/aco.0000000000001349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
PURPOSE OF REVIEW The advent of direct oral anticoagulants (DOACs) marks a significant milestone in anticoagulant treatment. However, DOACs can exacerbate bleeding, which is challenging for the treating clinician, especially when combined with traumatic injury. RECENT FINDINGS In major bleeding associated with DOACs, rapid reversal of the anticoagulant effects is crucial. Recent observational and nonrandomized interventional trials have demonstrated the effectiveness of the specific antidotes andexanet alfa and idarucizumab as well as the unspecific prothrombin complex concentrates (PCCs) to counteract the anticoagulant effects of DOACs. The European Society of Anaesthesiology and Intensive Care guideline for severe perioperative bleeding and the European trauma guideline propose divergent recommendations for the use of andexanet alfa and PCC to obtain hemostasis in Factor Xa inhibitor-related bleeding. The conflicting recommendations are due to limited evidence from clinical studies and the potential increased risk of thromboembolic complications after the administration of andexanet. Regarding dabigatran-associated major bleeding, both guidelines recommend the specific reversal agent idarucizumab as first-line therapy. SUMMARY Current guidelines recommend specific antidots and PCCs in DOAC-related major bleeding. Prospective randomized trials comparing specific vs. nonspecific hemostatic agents in the perioperative setting are needed to evaluate the effectiveness and safety of the hemostatic agents.
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Affiliation(s)
- Jan Wienhold
- Department of Anaesthesiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Farahnaz Rayatdoost
- Department of Anaesthesiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Herbert Schöchl
- Ludwig Boltzmann Institute for Traumatology, The Research Centre in Cooperation with AUVA, Vienna, Austria
| | - Oliver Grottke
- Department of Anaesthesiology, RWTH Aachen University Hospital, Aachen, Germany
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Rayatdoost F, Braunschweig T, Schöchl H, Rossaint R, Grottke O. Dose-Related Effectiveness of Andexanet Alfa for Reversal of Apixaban Anticoagulation in a Porcine Polytrauma Model. Thromb Haemost 2024; 124:20-31. [PMID: 37604188 DOI: 10.1055/s-0043-1772697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/23/2023]
Abstract
BACKGROUND Andexanet alfa (andexanet) is a reversal agent for use in patients with life-threatening or uncontrolled bleeding treated with oral factor Xa (FXa) inhibitors. There are limited data on the dose-response relationship of andexanet and FXa inhibitor-related bleeding. OBJECTIVE The aim of this study was to assess the dose-related effectiveness of andexanet in reducing blood loss, improving survival, and reversing apixaban anticoagulation in a porcine polytrauma model. METHODS Apixaban was given orally to 40 male pigs for 3 days at a dose of 20 mg/d. On day 3, following bilateral femur fractures and blunt liver injury, animals (n = 8/group) received andexanet (250-mg bolus, 250-mg bolus + 300-mg 2-hour infusion, 500-mg bolus, or 500-mg bolus + 600-mg 2-hour infusion) or vehicle (control). Total blood loss was the primary endpoint. Coagulation parameters were assessed for 300 minutes or until death. Data were analyzed with a mixed-model analysis of variance. RESULTS Administration of 250-mg bolus + 300-mg infusion, andexanet 500-mg bolus, and 500-mg bolus + 600-mg infusion significantly decreased total blood loss by 37, 58, and 61%, respectively (all p < 0.0001), with 100% survival. Andexanet 250-mg bolus was ineffective in reducing total blood loss (6%) and mortality (63% survival) versus controls. Andexanet 500-mg bolus ± infusion neutralized anti-FXa activity to less than 50 ng/mL. Andexanet neutralization of thrombin generation and thromboelastometry parameters was dose and infusion time dependent. CONCLUSION In a porcine polytrauma model with major bleeding on apixaban, andexanet dose dependently decreased anti-FXa activity. Lower anti-FXa levels (<50 ng/mL) with andexanet 500-mg bolus ± infusion were correlated with 60% less blood loss and 100% survival versus controls.
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Affiliation(s)
- Farahnaz Rayatdoost
- Department of Anaesthesiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Till Braunschweig
- Department of Pathology, RWTH Aachen University Hospital, Aachen, Germany
| | - Herbert Schöchl
- Department of Anaesthesiology and Intensive Care Medicine, AUVA Trauma Centre Salzburg, Academic Teaching Hospital of the Paracelsus Medical University Salzburg, Salzburg, Austria
| | - Rolf Rossaint
- Department of Anaesthesiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Oliver Grottke
- Department of Anaesthesiology, RWTH Aachen University Hospital, Aachen, Germany
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Rayatdoost F, Grottke O. The Use of Large Animal Models in Trauma and Bleeding Studies. Hamostaseologie 2023; 43:360-373. [PMID: 37696297 DOI: 10.1055/a-2118-1431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2023] Open
Abstract
BACKGROUND Major trauma often results in significant bleeding and coagulopathy, posing a substantial clinical burden. To understand the underlying pathophysiology and to refine clinical strategies to overcome coagulopathy, preclinical large animal models are often used. This review scrutinizes the clinical relevance of large animal models in hemostasis research, emphasizing challenges in translating findings into clinical therapies. METHODS We conducted a thorough search of PubMed and EMBASE databases from January 1, 2010, to December 31, 2022. We used specific keywords and inclusion/exclusion criteria centered on large animal models. RESULTS Our review analyzed 84 pertinent articles, including four animal species: pigs, sheep, dogs, and nonhuman primates (NHPs). Eighty-five percent of the studies predominantly utilized porcine models. Meanwhile, sheep and dogs were less represented, making up only 2.5% of the total studies. Models with NHP were 10%. The most frequently used trauma models involved a combination of liver injury and femur fractures (eight studies), arterial hemorrhage (seven studies), and a combination of hemodilution and liver injury (seven studies). A wide array of coagulation parameters were employed to assess the efficacy of interventions in hemostasis and bleeding control. CONCLUSIONS Recognizing the diverse strengths and weaknesses of large animal models is critical for trauma and hemorrhage research. Each model is unique and should be chosen based on how well it aligns with the specific scientific objectives of the study. By strategically considering each model's advantages and limitations, we can enhance our understanding of trauma and hemorrhage pathophysiology and further advance the development of effective treatments.
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Affiliation(s)
- Farahnaz Rayatdoost
- Department of Anaesthesiology, University Hospital RWTH Aachen, Aachen, Germany
| | - Oliver Grottke
- Department of Anaesthesiology, University Hospital RWTH Aachen, Aachen, Germany
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Sarode R, Welsby IJ, Hoffman M. Clinical Relevance of Preclinical and Clinical Studies of Four-Factor Prothrombin Complex Concentrate for Treatment of Bleeding Related to Direct Oral Anticoagulants. Ann Emerg Med 2023; 82:341-361. [PMID: 37204347 DOI: 10.1016/j.annemergmed.2023.04.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 04/06/2023] [Accepted: 04/13/2023] [Indexed: 05/20/2023]
Abstract
Direct oral anticoagulants (DOACs) are widely used for the prevention and treatment of venous thromboembolism and stroke. When emergency reversal of DOAC-related anticoagulation is required, specific DOAC reversal agents are recommended, including idarucizumab for dabigatran reversal and andexanet alfa for apixaban and rivaroxaban reversal. However, specific reversal agents are not always available, andexanet alfa has not been approved for urgent surgery, and clinicians need to know the patient's anticoagulant medication before administering these treatments. Four-factor prothrombin complex concentrates (4F-PCCs) are recognized as nonspecific, alternative hemostatic agents for treatment of DOAC-related bleeding. Evidence from preclinical and clinical studies shows that they may reduce the anticoagulant effects of DOACs and may help control DOAC-related bleeding. However, randomized controlled trials are lacking, and most data are from retrospective or single-arm prospective studies in bleeding associated with activated factor X inhibitors. There are no clinical data showing the efficacy of 4F-PCC for the treatment of bleeding in dabigatran-treated patients. This review focuses on the current evidence of 4F-PCC use in controlling bleeding associated with DOACs and provides an expert opinion on the relevance of these data for clinical practice. The current treatment landscape, unmet needs, and future directions are also discussed.
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Affiliation(s)
- Ravi Sarode
- Department of Pathology and Internal Medicine (Hematology/Oncology), UT Southwestern Medical Center, Dallas, TX.
| | - Ian J Welsby
- Department of Medicine, Duke University School of Medicine, Durham, NC
| | - Maureane Hoffman
- Department of Pathology, Duke University School of Medicine, Durham, NC
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Salter B, Crowther M. A Historical Perspective on the Reversal of Anticoagulants. Semin Thromb Hemost 2022; 48:955-970. [PMID: 36055273 DOI: 10.1055/s-0042-1753485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
There has been a landmark shift in the last several decades in the management and prevention of thromboembolic events. From the discovery of parenteral and oral agents requiring frequent monitoring as early as 1914, to the development of direct oral anticoagulants (DOACs) that do not require monitoring or dose adjustment in the late 20th century, great advances have been achieved. Despite the advent of these newer agents, bleeding continues to be a key complication, affecting 2 to 4% of DOAC-treated patients per year. Bleeding is associated with substantial morbidity and mortality. Although specific reversal agents for DOACs have lagged the release of these agents, idarucizumab and andexanet alfa are now available as antagonists. However, the efficacy of these reversal agents is uncertain, and complications, including thrombosis, have not been adequately explored. As such, guidelines continue to advise the use of nonspecific prohemostatic agents for patients requiring reversal of the anticoagulant effect of these drugs. As the indications for DOACs and the overall prevalence of their use expand, there is an unmet need for further studies to determine the efficacy of specific compared with nonspecific pro-hemostatic reversal agents. In this review, we will discuss the evidence behind specific and nonspecific reversal agents for both parenteral and oral anticoagulants.
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Affiliation(s)
- Brittany Salter
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Mark Crowther
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada
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Dabigatran in Cerebral Sinus Vein Thrombosis and Thrombophilia. LIFE (BASEL, SWITZERLAND) 2022; 12:life12070970. [PMID: 35888060 PMCID: PMC9316430 DOI: 10.3390/life12070970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 06/22/2022] [Accepted: 06/27/2022] [Indexed: 11/16/2022]
Abstract
Background and Purpose: Thrombophilic gene alterations are a major risk factor for cerebral sinus vein thrombosis (CSVT). Up to 30% of all patients with cerebral sinus vein thrombosis (CSVT) are found to have thrombophilic defects such as prothrombin mutation (PTM) or factor V Leiden (FVL). Their repercussions on the plasma levels of dabigatran etexilate are unclear. In this prospective case–control study, we aimed to investigate whether thrombophilia in CSVT has an influence on dabigatran peak-plasma levels. Methods: We monitored 10 patients over 12 months with acute CSVT, genetic thrombophilia with off-label use of dabigatran etexilate 150 mg twice a day and measured dabigatran peak-plasma levels and radiological outcome. We also monitored patients without genetic thrombophilia with dabigatran etexilate 150 mg twice a day and compared the efficiency and dabigatran peak-plasma levels. Results: Patients with homozygote PTM had significantly lower dabigatran peak concentration compared to patients with FVL or the control group (23 ± 4.2 vs. 152.3 ± 27.5 and 159.6 ± 63.08; p-value ≤ 0.05) There was no significant difference in dabigatran etexilate plasma levels between the heterozygote PTM group compared to patients with FVL or the control group (p = 0.29). There was no correlation between dabigatran peak concentration and delayed thrombus dissolution. Conclusions: Dabigatran peak concentration was stable in patients with heterozygote FVL and heterozygote PTM, but not in homozygote PTM, compared to controls. Genetic screening for thrombophilia in patients after CSVT may be useful to make patient tailored therapeutic decisions regarding oral anticoagulation and may decrease thrombotic events.
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Brinkman HJM, Swieringa F, Zuurveld M, Veninga A, Brouns SLN, Heemskerk JWM, Meijers JCM. Reversing direct factor Xa or thrombin inhibitors: Factor V addition to prothrombin complex concentrate is beneficial in vitro. Res Pract Thromb Haemost 2022; 6:e12699. [PMID: 35494506 PMCID: PMC9036856 DOI: 10.1002/rth2.12699] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 03/02/2022] [Accepted: 03/07/2022] [Indexed: 12/23/2022] Open
Abstract
Background Prothrombin complex concentrate (PCC) is a human plasma‐derived mixture of partially purified vitamin K‐dependent coagulation factors (VKCF). Current therapeutic indication is treatment and perioperative prophylaxis of bleeding in acquired VKCF deficiency. Off‐label uses include treatment of direct factor Xa‐ or thrombin inhibitor‐associated bleeds, treatment of trauma‐induced coagulopathy, and hemorrhagic complications in patients with liver disease. Objective Considering PCC as a general prohemostatic drug, we argued that its clinical efficacy can benefit from supplementation with coagulation factors that are absent in the current PCC formulation. In this study, we focused on factor V. Methods We mimicked a coagulopathy in vitro by spiking whole blood or derived plasma with the direct oral anticoagulants (DOAC) rivaroxaban or dabigatran. We studied DOAC reversal by PCC and factor V concentrate (FVC) using a thrombin generation assay, thromboelastography, fibrin generation clot lysis test, and microfluidic thrombus formation under flow. Results In DOAC‐treated plasma, PCC increased the amount of thrombin generated. The addition of FVC alone or in combination with PCC caused a partial correction of the thrombin generation lag time and clotting time. In DOAC‐treated whole blood, the combination of PCC and FVC synergistically improved clotting time under static conditions, whereas complete correction of fibrin formation was observed under flow. Clot strength and clot resistance toward tissue plasminogen activator‐induced lysis were both increased with PCC and further enhanced by additional FVC. Conclusion Our in vitro study demonstrates a beneficial effect of the combined use of PCC and FVC in DOAC reversal.
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Affiliation(s)
| | - Frauke Swieringa
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM) Maastricht University Maastricht The Netherlands
- Synapse Research Institute Maastricht The Netherlands
| | - Marleen Zuurveld
- Department of Molecular Hematology Sanquin Research Amsterdam The Netherlands
| | - Alicia Veninga
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM) Maastricht University Maastricht The Netherlands
| | - Sanne L. N. Brouns
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM) Maastricht University Maastricht The Netherlands
| | - Johan W. M. Heemskerk
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM) Maastricht University Maastricht The Netherlands
- Synapse Research Institute Maastricht The Netherlands
| | - Joost C. M. Meijers
- Department of Molecular Hematology Sanquin Research Amsterdam The Netherlands
- Department of Experimental Vascular Medicine Amsterdam Cardiovascular Sciences Amsterdam UMC University of Amsterdam Amsterdam The Netherlands
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Pavoni V, Gianesello L, Conti D, Ballo P, Dattolo P, Prisco D, Görlinger K. "In Less than No Time": Feasibility of Rotational Thromboelastometry to Detect Anticoagulant Drugs Activity and to Guide Reversal Therapy. J Clin Med 2022; 11:1407. [PMID: 35268498 PMCID: PMC8911211 DOI: 10.3390/jcm11051407] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 02/23/2022] [Accepted: 03/03/2022] [Indexed: 02/04/2023] Open
Abstract
Anticoagulant drugs (i.e., unfractionated heparin, low-molecular-weight heparins, vitamin K antagonists, and direct oral anticoagulants) are widely employed in preventing and treating venous thromboembolism (VTE), in preventing arterial thromboembolism in nonvalvular atrial fibrillation (NVAF), and in treating acute coronary diseases early. In certain situations, such as bleeding, urgent invasive procedures, and surgical settings, the evaluation of anticoagulant levels and the monitoring of reversal therapy appear essential. Standard coagulation tests (i.e., activated partial thromboplastin time (aPTT) and prothrombin time (PT)) can be normal, and the turnaround time can be long. While the role of viscoelastic hemostatic assays (VHAs), such as rotational thromboelastometry (ROTEM), has successfully increased over the years in the management of bleeding and thrombotic complications, its usefulness in detecting anticoagulants and their reversal still appears unclear.
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Affiliation(s)
- Vittorio Pavoni
- Anesthesia and Intensive Care Unit, Emergency Department and Critical Care Area, Santa Maria Annunziata Hospital, Bagno a Ripoli, 50012 Florence, Italy; (V.P.); (D.C.)
| | - Lara Gianesello
- Department of Anesthesia and Intensive Care, Orthopedic Anesthesia, University-Hospital Careggi, 50134 Florence, Italy
| | - Duccio Conti
- Anesthesia and Intensive Care Unit, Emergency Department and Critical Care Area, Santa Maria Annunziata Hospital, Bagno a Ripoli, 50012 Florence, Italy; (V.P.); (D.C.)
| | - Piercarlo Ballo
- Cardiology Unit, Santa Maria Annunziata Hospital, Bagno a Ripoli, 50012 Florence, Italy;
| | - Pietro Dattolo
- Nephrology Unit Florence 1, Santa Maria Annunziata Hospital, Bagno a Ripoli, 50012 Florence, Italy;
| | - Domenico Prisco
- Department of Experimental and Clinical Medicine, University of Florence, 50134 Florence, Italy;
| | - Klaus Görlinger
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Essen, University Duisburg-Essen, 45147 Essen, Germany;
- Medical Department, Tem Innovations, 81829 Munich, Germany
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Maisha N, Rubenstein M, Bieberich CJ, Lavik E. Getting to the Core of It All: Nanocapsules to Mitigate Infusion Reactions Can Promote Hemostasis and Be a Platform for Intravenous Therapies. NANO LETTERS 2021; 21:9069-9076. [PMID: 34714087 DOI: 10.1021/acs.nanolett.1c02746] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
One of the significant challenges to translation of intravenously administered nanomaterials has been complement-mediated infusion reactions which can be lethal. Slow infusions can reduce infusion reactions, but slow infusions are not always possible in applications like controlling bleeding following trauma. Thus, avoiding complement activation and infusion responses is essential to manage bleeding. We identified nanocapsules based on polyurethane as candidates that did not activate C5a and explored their PEGylation and functionalization with the GRGDS peptide to create a new class of hemostatic nanomaterials. Using the clinically relevant rotational thromboelastography (ROTEM), we determined that nanocapsules promote faster clotting than controls and maintain the maximum clot firmness, which is critical for reducing bleeding. Excitingly, these polyurethane-based nanocapsules did not activate complement or the major pro-inflammatory cytokines. This work provides critical evidence for the role of modulating the core material in developing safer nanomedicines for intravenous applications.
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Affiliation(s)
- Nuzhat Maisha
- University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250, United States
| | - Michael Rubenstein
- University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250, United States
| | - Charles J Bieberich
- University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250, United States
| | - Erin Lavik
- University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250, United States
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Ghosh S, Krege W, Doerr B, Mischnik M, Pragst I, Dickneite G, Herzog E. Evaluation of the prothrombotic potential of four-factor prothrombin complex concentrate (4F-PCC) in animal models. PLoS One 2021; 16:e0258192. [PMID: 34614035 PMCID: PMC8494364 DOI: 10.1371/journal.pone.0258192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 09/21/2021] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES Acquired coagulopathy may be associated with bleeding risk. Approaches to restore haemostasis include administration of coagulation factor concentrates, but there are concerns regarding potential prothrombotic risk. The present study assessed the prothrombotic potential of four-factor prothrombin complex concentrate (4F-PCC) versus activated PCC (aPCC) and recombinant factor VIIa (rFVIIa), using three preclinical animal models. METHODS The first model was a modified Wessler model of venous stasis-induced thrombosis in rabbit, focusing on dilutional coagulopathy; the second model employed the same system but focused on direct oral anticoagulant reversal (i.e. edoxaban). The third model assessed the prothrombotic impact of 4F-PCC, aPCC and rFVIIa in a rat model of ferric chloride-induced arterial thrombosis. RESULTS In the first model, thrombi were observed at aPCC doses ≥10 IU/kg (therapeutic dose 100 IU/kg) and rFVIIa doses ≥50 μg/kg (therapeutic dose 90 μg/kg), but not 4F-PCC 50 IU/kg (therapeutic dose 50 IU/kg). The impact of 4F-PCC (up to 300 IU/kg) on thrombus formation was evident from 10 minutes post-administration, but not at 24 hours post-administration; this did not change with addition of tranexamic acid and/or fibrinogen concentrate. 4F-PCC-induced thrombus formation was lower after haemodilution versus non-haemodilution. In the second model, no prothrombotic effect was confirmed at 4F-PCC 50 IU/kg. The third model showed lower incidence of thrombus formation for 4F-PCC 50 IU/kg versus aPCC (50 U/kg) and rFVIIa (90 μg/kg). CONCLUSIONS These results suggest that 4F-PCC has a low thrombotic potential versus aPCC or rFVIIa, supporting the clinical use of 4F-PCC for the treatment of coagulopathy-mediated bleeding.
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Affiliation(s)
- Subhajit Ghosh
- Department of Pharmacology and Toxicology, CSL Behring GmbH, Marburg, Germany
| | - Wilfred Krege
- Department of Pharmacology and Toxicology, CSL Behring GmbH, Marburg, Germany
| | - Baerbel Doerr
- Department of Pharmacology and Toxicology, CSL Behring GmbH, Marburg, Germany
| | - Marcel Mischnik
- Department of Pharmacology and Toxicology, CSL Behring GmbH, Marburg, Germany
| | - Ingo Pragst
- Department of Clinical Research and Development, CSL Behring GmbH, Marburg, Germany
| | - Gerhard Dickneite
- Department of Pharmacology and Toxicology, CSL Behring GmbH, Marburg, Germany
| | - Eva Herzog
- Department of Pharmacology and Toxicology, CSL Behring GmbH, Marburg, Germany
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Reversing Rivaroxaban Anticoagulation as Part of a Multimodal Hemostatic Intervention in a Polytrauma Animal Model. Anesthesiology 2021; 135:673-685. [PMID: 34370811 DOI: 10.1097/aln.0000000000003899] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Life-threatening bleeding requires prompt reversal of the anticoagulant effects of factor Xa inhibitors. This study investigated the effectiveness of four-factor prothrombin complex concentrate in treating trauma-related hemorrhage with rivaroxaban-anticoagulation in a pig polytrauma model. This study also tested the hypothesis that the combined use of a low dose of prothrombin complex concentrate plus tranexamic acid and fibrinogen concentrate could improve its subtherapeutic effects. METHODS Trauma (blunt liver injury and bilateral femur fractures) was induced in 48 anesthetized male pigs after 30 min of rivaroxaban infusion (1 mg/kg). Animals in the first part of the study received prothrombin complex concentrate (12.5, 25, and 50 U/kg). In the second part, animals were treated with 12.5 U/kg prothrombin complex concentrate plus tranexamic acid or plus tranexamic acid and fibrinogen concentrate. The primary endpoint was total blood loss postinjury. The secondary endpoints (panel of coagulation parameters and thrombin generation) were monitored for 240 min posttrauma or until death. RESULTS The first part of the study showed that blood loss was significantly lower in the 25 U/kg prothrombin complex concentrate (1,541 ± 269 ml) and 50 U/kg prothrombin complex concentrate (1,464 ± 108 ml) compared with control (3,313 ± 634 ml), and 12.5 U/kg prothrombin complex concentrate (2,671 ± 334 ml, all P < 0.0001). In the second part of the study, blood loss was significantly less in the 12.5 U/kg prothrombin complex concentrate plus tranexamic acid and fibrinogen concentrate (1,836 ± 556 ml, P < 0.001) compared with 12.5 U/kg prothrombin complex concentrate plus tranexamic acid (2,910 ± 856 ml), and there were no early deaths in the 25 U/kg prothrombin complex concentrate, 50 U/kg prothrombin complex concentrate, and 12.5 U/kg prothrombin complex concentrate plus tranexamic acid and fibrinogen concentrate groups. Histopathologic analyses postmortem showed no adverse events. CONCLUSIONS Prothrombin complex concentrate effectively reduced blood loss, restored hemostasis, and balanced thrombin generation. A multimodal hemostatic approach using tranexamic acid plus fibrinogen concentrate enhanced the effect of low doses of prothrombin complex concentrate, potentially reducing the prothrombin complex concentrate doses required for effective bleeding control. EDITOR’S PERSPECTIVE
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Tanaka KA, Henderson RA, Strauss ER. Evolution of viscoelastic coagulation testing. Expert Rev Hematol 2020; 13:697-707. [DOI: 10.1080/17474086.2020.1758929] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
| | | | - Erik R. Strauss
- School of Medicine, University of Maryland, Baltimore, MD, USA
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Four-factor Prothrombin Complex Concentrate for the Management of Patients Receiving Direct Oral Activated Factor X Inhibitors. Anesthesiology 2019; 131:1153-1165. [DOI: 10.1097/aln.0000000000002910] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Factor Xa inhibitors prevent thrombosis but are associated with severe or life-threatening bleeding. Here, the authors present data on four-factor prothrombin complex concentrates in management of anticoagulation-associated bleeding and restoring hemostasis, including recent results from the UPRATE study.
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Transient or extended reversal of apixaban anticoagulation by andexanet alfa is equally effective in a porcine polytrauma model. Br J Anaesth 2019; 123:186-195. [PMID: 31202564 DOI: 10.1016/j.bja.2019.04.059] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Revised: 03/06/2019] [Accepted: 04/05/2019] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND Andexanet alfa (andexanet) reverses the anticoagulant effects of factor Xa inhibitors, but it has not been assessed in clinical studies for apixaban reversal in trauma. This study evaluated andexanet for reversing apixaban anticoagulation in a porcine polytrauma model. METHODS Oral apixaban (20 mg q.d., n=21) or placebo (n=7; sham group) was administered to male pigs for 4 days before blunt liver injury and bi-lateral femur fracture. After trauma, animals were randomised 1:1:1 to a single andexanet bolus (1000 mg), a bolus (1000 mg) plus infusion (1200 mg over 2 h), or vehicle (control). Haemodynamic and coagulation variables were monitored for 5 h or until death. The primary endpoint was blood loss. RESULTS Mean blood loss in sham animals was 472 (standard deviation, 58) ml 12 min after injury and 658 (98) ml at 300 min, with 100% survival. Anticoagulation with apixaban significantly increased blood loss 12 min after injury [888 (133) ml, P<0.01]. Controls exhibited total blood loss of 3403 (766) ml, with 100% mortality. Andexanet bolus or bolus plus infusion significantly reduced blood loss to 1264 (205) and 1202 (95) ml, respectively), and increased survival to 100%. Haemodynamic parameters and markers of shock recovered to pre-trauma levels in andexanet-treated animals. CONCLUSION Andexanet effectively reversed apixaban anticoagulation and reduced blood loss induced by severe trauma. Andexanet bolus alone had a similar impact on survival and blood loss as bolus plus infusion. Therefore, a 2 h andexanet infusion after the bolus may not be necessary to restore normal haemostatic mechanisms.
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Dias JD, Lopez-Espina CG, Ippolito J, Hsiao LH, Zaman F, Muresan AA, Thomas SG, Walsh M, Jones AJ, Grisoli A, Thurston BC, Artang R, Bilden KP, Hartmann J, Achneck HE. Rapid point-of-care detection and classification of direct-acting oral anticoagulants with the TEG 6s: Implications for trauma and acute care surgery. J Trauma Acute Care Surg 2019; 87:364-370. [DOI: 10.1097/ta.0000000000002357] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Honickel M, Braunschweig T, Rossaint R, Schöchl H, Grottke O. Evaluation of combined idarucizumab and prothrombin complex concentrate treatment for bleeding related to dabigatran in a lethal porcine model of double trauma. Transfusion 2018; 59:1376-1387. [PMID: 30586470 DOI: 10.1111/trf.15117] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 10/23/2018] [Accepted: 10/23/2018] [Indexed: 12/20/2022]
Abstract
BACKGROUND Idarucizumab (IDA) is approved for emergency reversal of dabigatran; prothrombin complex concentrates (PCCs) are recommended in the absence of specific antidote. The combined effects of IDA and PCC in trauma-related bleeding are unknown. The efficacy and safety of combined IDA + PCC were assessed in a lethal porcine model of double trauma under dabigatran anticoagulation. STUDY DESIGN AND METHODS Male pigs (n = 28) received oral dabigatran etexilate (30 mg/kg bid) for 3 days; a non-dabigatran control group (n = 7) received placebo. On Day 4, dabigatran-treated animals were randomized 1:1:1:1 to receive placebo + placebo (dabigatran-treated control), IDA + PCC (60 mg/kg + 50 IU/kg), PCC + IDA, or IDA + IDA. Trauma was induced at t = 0 (bilateral femur fractures and blunt liver injury) and t = 60 minutes (second blunt liver injury). Study treatment was administered 15 minutes after each trauma. Animals were monitored for 5 hours or until death. RESULTS Total blood loss in IDA + PCC, PCC + IDA, and IDA + IDA was 1673 ± 370, 1981 ± 361, and 1417 ± 135 mL, respectively, with 100% survival at 5 hours. Blood loss in dabigatran-treated controls was 4427 ± 162 mL with 100% mortality. With IDA + IDA, plasma coagulation parameters and thrombin generation were similar to non-dabigatran control group levels after the second dose and remained stable over time. In the IDA + PCC and PCC + IDA groups, thrombin generation and d-dimer levels after the second dose were higher than with IDA + IDA. No thromboembolic complications were found. CONCLUSION IDA and PCC are effective in treating trauma-related bleeding with dabigatran anticoagulation. IDA is preferable for emergency reversal of dabigatran, but PCC may be valuable when the anticoagulant is unknown.
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Affiliation(s)
- Markus Honickel
- Department of Anesthesiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Till Braunschweig
- Department of Pathology, RWTH Aachen University Hospital, Aachen, Germany
| | - Rolf Rossaint
- Department of Anesthesiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Herbert Schöchl
- AUVA Research Centre, Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria.,Department of Anaesthesiology and Intensive Care, AUVA Trauma Centre, Salzburg, Austria
| | - Oliver Grottke
- Department of Anesthesiology, RWTH Aachen University Hospital, Aachen, Germany
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Hoffman M, Goldstein JN, Levy JH. The impact of prothrombin complex concentrates when treating DOAC-associated bleeding: a review. Int J Emerg Med 2018; 11:55. [PMID: 31179943 PMCID: PMC6326120 DOI: 10.1186/s12245-018-0215-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 11/11/2018] [Indexed: 12/18/2022] Open
Abstract
Background Bleeding complications are a risk associated with all anticoagulants. Currently, the treatment options for the management of direct oral anticoagulant (DOAC)-associated bleeding are limited. Prothrombin complex concentrates (PCCs) have been proposed as a potential therapeutic option, and evidence regarding their use is increasing. Review Many studies supporting PCC have used preclinical models and healthy volunteers; however, more recently, observational studies have further improved insight into current DOAC reversal strategies. Multiple clinical practice guidelines now specifically suggest use of PCCs for this indication. Specific reversal agents for Factor Xa inhibitors may become available in the near future, but data on their efficacy are still emerging. Conclusions Ultimately, a multimodal approach may be the optimal strategy to restore haemostasis in patients presenting with DOAC-associated coagulopathy. Electronic supplementary material The online version of this article (10.1186/s12245-018-0215-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Maureane Hoffman
- Department of Pathology, Duke University School of Medicine, Durham, NC, USA.
| | - Joshua N Goldstein
- Department of Emergency Medicine, Massachusetts General Hospital, Boston, USA
| | - Jerrold H Levy
- Department of Anesthesiology and Critical Care, Duke University School of Medicine, Durham, NC, USA
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Use of DOAC Stop for elimination of anticoagulants in the thrombin generation assay. Thromb Res 2018; 170:97-101. [DOI: 10.1016/j.thromres.2018.08.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 08/20/2018] [Accepted: 08/21/2018] [Indexed: 11/18/2022]
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Grottke O, Lier H, Hofer S. [Management of hemorrhage in patients treated with direct oral anticoagulants]. Anaesthesist 2018; 66:679-689. [PMID: 28455651 DOI: 10.1007/s00101-017-0313-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The introduction of nonvitamin K antagonistic, direct oral anticoagulants (DOAC) made thromboembolic prophylaxis easier for patients. For many physicians, however, there is still uncertainty about monitoring, preoperative discontinuation, and restarting of DOAC therapy. Guidelines for the management of bleeding are provided, but require specific therapeutic skills in the management of diagnostics and therapy of acute hemorrhage. Small clinical studies and case reports indicate that unspecific therapy with prothrombin complex concentrates (PCC) and activated PCC (aPCC) concentrate may reverse DOAC-induced anticoagulation. However, PCC or aPCC at higher doses potentially provoke thromboembolic complications. However, idarucizumab, a specific, fast-acting, antidote for dabigatran, provides immediate and sustained reversal with no intrinsic or prohemostatic activity. This review article provides an overview of the pharmacology and potential risk of DOAC and the management in the perioperative period with a focus of current concepts in the treatment of DOAC-associated bleeding.
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Affiliation(s)
- O Grottke
- Klinik für Anästhesiologie, Experimentelle Hämostaseologie, Universitätsklinikum RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Deutschland.
| | - H Lier
- Klinik für Anästhesiologie und Operative Intensivmedizin, Universitätsklinikum Köln (AöR), Köln, Deutschland
| | - S Hofer
- Klinik für Anästhesie, Intensiv- und Notfallmedizin, Westpfalz-Klinikum GmbH, Kaiserslautern, Deutschland
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Belli EV, Lee T. Idarucizumab (Praxbind) for reversal of pradaxa prior to emergent repair of contained ruptured transverse arch aneurysm. Ann Card Anaesth 2018; 20:369-371. [PMID: 28701610 PMCID: PMC5535586 DOI: 10.4103/0971-9784.210426] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Idarucizumab before cardiopulmonary bypass was used for the reversal of dabigatran during an emergent frozen elephant trunk repair of a transverse arch aneurysm. Reversal was successful and minimal not massive transfusion was required with no abnormal sequelae seen with use before cardiopulmonary bypass.
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Affiliation(s)
- Erol Vahit Belli
- Department of Thoracic and Cardiovascular Surgery, University of Florida, Gainesville, FL 32611; Department of Cardiovascular Surgery, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Teng Lee
- Department of Thoracic and Cardiovascular Surgery, University of Florida, Gainesville, FL 32611, USA
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Shaw JR, Siegal DM. Pharmacological reversal of the direct oral anticoagulants-A comprehensive review of the literature. Res Pract Thromb Haemost 2018; 2:251-265. [PMID: 30046727 PMCID: PMC6055488 DOI: 10.1002/rth2.12089] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 01/31/2018] [Indexed: 11/11/2022] Open
Abstract
The direct oral anticoagulants (DOACs) are used for stroke prevention in atrial fibrillation (SPAF) and the prevention and treatment of venous thromboembolic disease (VTE). Although DOAC-associated bleeding events are less frequent as compared to vitamin K antagonists, there is significant concern surrounding physicians' ability to evaluate and manage DOAC-associated bleeding when it does occur. Idarucizumab is a specific reversal agent for dabigatran and is the agent of choice for dabigatran reversal in the setting of major bleeding or urgent surgery/procedures. There are no commercially available specific reversal agents for the direct Xa inhibitors. Although they have not been rigorously studied in DOAC-treated patients requiring urgent anticoagulant reversal, limited evidence from in vitro studies, animal bleeding models, human volunteer studies (in vivo and in vitro) and case series suggest that coagulation factor replacement with prothrombin complex concentrate (PCC) and activated PCC (FEIBA) may contribute to hemostasis. However, the safety and efficacy of these agents and the optimal dosing strategies remain uncertain.
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Affiliation(s)
- Joseph R Shaw
- Division of Hematology Department of Medicine The Ottawa Hospital Ottawa ON Canada.,Ottawa Hospital Research Institute Ottawa ON Canada.,Faculty of Medicine University of Ottawa Ottawa ON Canada
| | - Deborah M Siegal
- Division of Hematology and Thromboembolism Department of Medicine McMaster University Hamilton ON Canada.,Population Health Research Institute McMaster University Hamilton ON Canada
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Akman N, Braunschweig T, Honickel M, Schütt K, Schöchl H, Stoppe C, Rossaint R, Grottke O. Reversal of dabigatran by intraosseous or intravenous idarucizumab in a porcine polytrauma model. Br J Anaesth 2018; 120:978-987. [PMID: 29661415 DOI: 10.1016/j.bja.2018.01.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 01/05/2018] [Accepted: 01/31/2018] [Indexed: 10/17/2022] Open
Abstract
BACKGROUND Idarucizumab is licensed to reverse dabigatran in life-threatening haemorrhage. Establishment of venous access can be challenging, and the intraosseous (IO) route is a potentially life-saving alternative. In this study, we compared the efficacy and safety of IO or intravenous (i.v.) idarucizumab for dabigatran reversal in a porcine polytrauma model. METHODS Male pigs (n=21) received oral dabigatran etexilate (30 mg kg-1 bid) for 3 days. On the 4th day, animals received dabigatran infusion and were randomised 1:1:1 to receive IO saline (control), i.v. idarucizumab (60 mg kg-1), or IO idarucizumab (60 mg kg-1), or animals were included in a sham group (n=7). Study treatment was administered after polytrauma and the animals were monitored for 240 min, or until death. Coagulation status was monitored by thromboelastometry, thromboelastography, and thrombin measurements. RESULTS Total blood loss was lowest in sham animals [521 (52) ml, P<0.01 vs all other groups], and comparable in the two idarucizumab groups [IO: 1085 (102) ml vs i.v.: 1142 (125) ml], and highest in the control group [4065 (557) ml, P<0.001 vs all other groups]. Survival to 240 min was 100% in the sham group and both idarucizumab groups, and 14% in the control group. IO and i.v. idarucizumab promptly normalised global coagulation assays and thrombin generation. Thromboelastography showed a strong correlation between dabigatran concentrations and R-time (R2=0.90 and 0.89) in idarucizumab-treated animals. CONCLUSIONS Intravenous and intraosseous idarucizumab were comparable for reversing dabigatran in a porcine trauma model. Dabigatran reversal could be monitored using fully automated thromboelastography.
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Affiliation(s)
- N Akman
- Department of Anaesthesiology, RWTH Aachen University Hospital, Aachen, Germany
| | - T Braunschweig
- Department of Pathology, RWTH Aachen University Hospital, Aachen, Germany
| | - M Honickel
- Department of Anaesthesiology, RWTH Aachen University Hospital, Aachen, Germany
| | - K Schütt
- Department of Internal Medicine I, RWTH Aachen University Hospital, Aachen, Germany
| | - H Schöchl
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Centre, Vienna, Austria; Department of Anaesthesiology and Intensive Care Medicine, AUVA Emergency Hospital, Salzburg, Austria
| | - C Stoppe
- Department of Anaesthesiology, RWTH Aachen University Hospital, Aachen, Germany
| | - R Rossaint
- Department of Anaesthesiology, RWTH Aachen University Hospital, Aachen, Germany
| | - O Grottke
- Department of Anaesthesiology, RWTH Aachen University Hospital, Aachen, Germany.
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Maegele M, Grottke O, Schöchl H, Sakowitz OA, Spannagl M, Koscielny J. Direct Oral Anticoagulants in Emergency Trauma Admissions. DEUTSCHES ARZTEBLATT INTERNATIONAL 2018; 113:575-82. [PMID: 27658470 DOI: 10.3238/arztebl.2016.0575] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 05/17/2016] [Accepted: 05/17/2016] [Indexed: 01/22/2023]
Abstract
BACKGROUND Direct (non-vitamin-K-dependent) oral anticoagulants (DOAC) are given as an alternative to vitamin K antagonists (VKA) to prevent stroke and embolic disease in patients with atrial fibrillation that is not due to pathology of the heart valves. Fatal hemorrhage is rarer when DOACs are given (nonvalvular atrial fibrillation: odds ratio [OR] 0.68; 95% confidence interval [95% CI: 0.48; 0.96], and venous thromboembolism: OR 0.54; [0.22; 1.32]). 48% of emergency trauma patients need an emergency operation or early surgery. Clotting disturbances elevate the mortality of such patients to 43%, compared to 17% in patients without a clotting disturbance. This underscores the impor tance of the proper, targeted treatment of trauma patients who are aking DOAC. METHODS This review is based on articles retrieved by a selective search in PubMed and on a summary of expert opinion and the recommendations of the relevant medical specialty societies. RESULTS Peak DOAC levels are reached 2-4 hours after the drug is taken. In patients with normal renal and hepatic function, no drug accumulation, and no drug interactions, the plasma level of DOAC 24 hours after administration is generally too low to cause any clinically relevant risk of bleeding. The risk of drug accumulation is higher in patients with renal dysfunction (creatinine clearance [CrCl] of 30 mL/min or less). Dabigatran levels can be estimated from the thrombin time, ecarin clotting time, and diluted thrombin time, while levels of factor Xa inhibitors can be estimated by means of calibrated chromogenic anti-factor Xa activity tests. Routine clotting studies do not reliably reflect the anticoagulant activity of DOAC. Surgery should be postponed, if possible, until at least 24-48 hours after the last dose of DOAC. For patients with mild, non-life threatening hemorrhage, it suffices to discontinue DOAC; for patients with severe hemorrhage, there are special treatment algorithms that should be followed. CONCLUSION DOACs in the setting of hemorrhage are a clinical challenge in the traumatological emergency room because of the inadequate validity of the relevant laboratory tests. An emergency antidote is now available only for dabigatran.
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Affiliation(s)
- Marc Maegele
- Department of Trauma and Orthopedic Sugery, Cologne-Merheim Medical Center (CMMC), Witten/Herdecke University, Cologne and Institute for Research in Operative Medicine (IFOM), Witten/Herdecke University, Campus Cologne-Merheim, Cologne, Experimental Hemostaseology, Department of Anesthesiology, University Hospital RWTH Aachen, Aachen, Department of Anesthesiology and Intensive Care Medicine, AUVA Emergency Hospital, Salzburg (Austria), Department of Neurosurgery, Ludwigsburg Hospital, Ludwigsburg, Department of Anesthesiology, Ludwig Maximilian University of Munich, Munich, Institute for Transfusion Medicine, Charité University Medicine Berlin, Berlin
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Reversing Dabigatran Anticoagulation with Prothrombin Complex Concentrate versus Idarucizumab as Part of Multimodal Hemostatic Intervention in an Animal Model of Polytrauma. Anesthesiology 2017; 127:852-861. [PMID: 28857806 DOI: 10.1097/aln.0000000000001856] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
BACKGROUND Although idarucizumab is the preferred treatment for urgent dabigatran reversal, it is not always available. Prothrombin complex concentrate (PCC) may be an alternative and, with bleeding in trauma, additional hemostatic therapy may be required. The authors investigated multimodal treatment in a preclinical polytrauma model. METHODS Dabigatran etexilate (30 mg/kg twice daily) was given orally to 45 male pigs for 3 days. On day 4, animals received a dabigatran infusion before blunt liver injury and bilateral femur fractures. After injury, animals were randomized 1:1:1:1:1 to receive placebo (control), tranexamic acid (TXA; 20 mg/kg) plus human fibrinogen concentrate (FCH; 80 mg/kg) (TXA-FCH group), PCC (25 U/kg or 50 U/kg) plus TXA plus FCH (PCC25 and PCC50 groups), or 60 mg/kg idarucizumab (IDA) plus TXA plus FCH (IDA group). Animals were monitored for 240 min after trauma, or until death. RESULTS The degree of injury was similar in all animals before intervention. Control and TXA-FCH animals had the highest total postinjury blood loss (3,652 ± 601 and 3,497 ± 418 ml) and 100% mortality (mean survival time 96 and 109 min). Blood loss was significantly lower in the PCC50 (1,367 ± 273 ml) and IDA (986 ± 144 ml) groups, with 100% survival. Thrombin-antithrombin levels and thrombin generation were significantly elevated in the PCC50 group. CONCLUSIONS Idarucizumab may be considered the optimal treatment for emergency reversal of dabigatran anticoagulation. However, this study suggests that PCC may be similarly effective as idarucizumab and could therefore be valuable when idarucizumab is unavailable. (Anesthesiology 2017; 127:852-61).
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De Vlieger J, Dietvorst S, Demaerel R, Verhamme P, Nuttin B, Vanassche T. Neurosurgery in a patient at peak levels of rivaroxaban: taking into account all factors. Res Pract Thromb Haemost 2017; 1:296-300. [PMID: 30046700 PMCID: PMC6058271 DOI: 10.1002/rth2.12035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 07/13/2017] [Indexed: 11/20/2022] Open
Abstract
We present a patient who underwent urgent neurosurgery for acute onset paraplegia due to a spontaneous subdural spinal hematoma less than 5 hours after she had taken rivaroxaban. The Key Clinical Question was whether early high-risk surgery on a patient taking direct oral anticoagulants is feasible. Prothrombin complex concentrate (PCC) and tranexamic acid were administered and perioperative hemostasis was good. There is scant data on neurosurgical procedures performed within 12 hours after the intake of a direct oral anticoagulant. With the hemostatic support of high-dose PCC, early surgery after administration of rivaroxaban seems feasible in case of an emergency indication, but should only be considered when delaying surgery is esteemed hazardous to the patient. More experience is needed to allow balancing risks and benefits of urgent vs delayed intervention and on the optimal hemostatic support in the absence of a specific antidote.
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Affiliation(s)
- Jan De Vlieger
- Department of NeurosurgeryUniversity Hospitals LeuvenLeuvenBelgium
| | - Sofie Dietvorst
- Department of NeurosurgeryUniversity Hospitals LeuvenLeuvenBelgium
| | - Rik Demaerel
- Department of NeurosurgeryUniversity Hospitals LeuvenLeuvenBelgium
| | - Peter Verhamme
- Department of Cardiovascular SciencesUniversity Hospitals LeuvenLeuvenBelgium
| | - Bart Nuttin
- Department of NeurosurgeryUniversity Hospitals LeuvenLeuvenBelgium
| | - Thomas Vanassche
- Department of Cardiovascular SciencesUniversity Hospitals LeuvenLeuvenBelgium
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Vornicu O, Larock AS, Dincq AS, Douxfils J, Dogné JM, Mullier F, Lessire S. Idarucizumab for the treatment of hemorrhage and dabigatran reversal in patients requiring urgent surgery or procedures. Expert Opin Biol Ther 2017; 17:1275-1296. [DOI: 10.1080/14712598.2017.1349749] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Ovidiu Vornicu
- Department of Anesthesiology, Université catholique de Louvain, CHU UCL Namur, Yvoir, Belgium
| | - Anne-Sophie Larock
- Namur Thrombosis and Hemostasis Center (NTHC) – NAmur Research Institute of LIfe Sciences (NARILIS), Namur, Belgium
- Department of Pharmacy, Université catholique de Louvain, CHU UCL Namur, Yvoir, Belgium
| | - Anne-Sophie Dincq
- Department of Anesthesiology, Université catholique de Louvain, CHU UCL Namur, Yvoir, Belgium
- Namur Thrombosis and Hemostasis Center (NTHC) – NAmur Research Institute of LIfe Sciences (NARILIS), Namur, Belgium
| | - Jonathan Douxfils
- Namur Thrombosis and Hemostasis Center (NTHC) – NAmur Research Institute of LIfe Sciences (NARILIS), Namur, Belgium
- Department of Pharmacy, Faculty of Medicine, Université de Namur, Namur, Belgium
| | - Jean-Michel Dogné
- Namur Thrombosis and Hemostasis Center (NTHC) – NAmur Research Institute of LIfe Sciences (NARILIS), Namur, Belgium
- Department of Pharmacy, Faculty of Medicine, Université de Namur, Namur, Belgium
| | - François Mullier
- Namur Thrombosis and Hemostasis Center (NTHC) – NAmur Research Institute of LIfe Sciences (NARILIS), Namur, Belgium
- Hematology Laboratory, Université catholique de Louvain, CHU UCL Namur, Yvoir, Belgium
| | - Sarah Lessire
- Department of Anesthesiology, Université catholique de Louvain, CHU UCL Namur, Yvoir, Belgium
- Namur Thrombosis and Hemostasis Center (NTHC) – NAmur Research Institute of LIfe Sciences (NARILIS), Namur, Belgium
- Department of Pharmacy, Faculty of Medicine, Université de Namur, Namur, Belgium
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Abstract
Several direct oral anticoagulants (DOACs), including direct thrombin and factor Xa inhibitors, have been approved as alternatives to vitamin K antagonist anticoagulants. As with any anticoagulant, DOAC use carries a risk of bleeding. In patients with major bleeding or needing urgent surgery, reversal of DOAC anticoagulation may be required, presenting a clinical challenge. The optimal strategy for DOAC reversal is being refined, and may include use of hemostatic agents such as prothrombin complex concentrates (PCCs; a source of concentrated clotting factors), or DOAC-specific antidotes (which bind their target DOAC to abrogate its activity). Though promising, most specific antidotes are still in development.Preclinical animal research is the key to establishing the efficacy and safety of potential reversal agents. Here, we summarize published preclinical animal studies on reversal of DOAC anticoagulation. These studies (n = 26) were identified via a PubMed search, and used rodent, rabbit, pig, and non-human primate models. The larger of these animals have the advantages of similar blood volume/hemodynamics to humans, and can be used to model polytrauma. We find that in addition to varied species being used, there is variability in the models and assays used between studies; we suggest that blood loss (bleeding volume) is the most clinically relevant measure of DOAC anticoagulation-related bleeding and its reversal.The studies covered indicate that both PCCs and specific reversal agents have the potential to be used as part of a clinical strategy for DOAC reversal. For the future, we advocate the development and use of standardized, clinically, and pharmacologically relevant animal models to study novel DOAC reversal strategies.
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Koscielny J, Rosenthal C, von Heymann C. Nicht-Vitamin-K-abhängige orale Antikoagulanzien. Notf Rett Med 2017. [DOI: 10.1007/s10049-017-0289-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Gottlieb M, Khishfe B. Idarucizumab for the Reversal of Dabigatran. Ann Emerg Med 2017; 69:554-558. [DOI: 10.1016/j.annemergmed.2016.11.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Indexed: 10/20/2022]
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Abstract
Idarucizumab is a monoclonal antibody fragment specifically targeted to dabigatran. It has demonstrated prompt and durable reversal of the anticoagulant effects of dabigatran in animal studies and phase 1 studies of young, elderly, and renally impaired volunteers. Although elective invasive procedures and most bleeding complications in dabigatran-treated patients can be managed by temporarily stopping dabigatran therapy and using supportive measures, there are rare clinical situations that require urgent reversal of the anticoagulant effect of dabigatran. The effectiveness and safety of 5 g of intravenous idarucizumab is being investigated in a prospective, open-label, single-cohort study in patients with serious bleeding or in those requiring an urgent procedure. In an interim analysis of the first 90 participants, idarucizumab rapidly and completely reversed the anticoagulant activity of dabigatran in 88%-98% of participants, and there were no safety concerns, with no deaths or serious adverse events being attributable to idarucizumab. Supported by these interim results, idarucizumab has been approved in the United States and the European Union for use when reversal of the anticoagulant effects of dabigatran is needed for emergency surgery/urgent procedures or in patients with life-threatening or uncontrolled bleeding. Clinical use of idarucizumab should follow the same processes as patient enrollment in this study, which is projected to be completed in 2016. The outcomes achieved with this specific reversal agent are likely to be of continued interest to treating physicians.
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Affiliation(s)
- Charles V Pollack
- Department of Emergency Medicine, Thomas Jefferson University, Philadelphia, PA.
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32
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Abstract
The risk of bleeding in the setting of anticoagulant therapy continues to be re-evaluated following the introduction of a new generation of direct oral anticoagulants (DOACs). Interruption of DOAC therapy and supportive care may be sufficient for the management of patients who present with mild or moderate bleeding, but in those with life-threatening bleeding, a specific reversal agent is desirable. We review the phase 3 clinical studies of dabigatran, rivaroxaban, apixaban, and edoxaban in patients with nonvalvular atrial fibrillation, in the context of bleeding risk and management.
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Idarucizumab, a Specific Reversal Agent for Dabigatran: Mode of Action, Pharmacokinetics and Pharmacodynamics, and Safety and Efficacy in Phase 1 Subjects. Am J Med 2016; 129:S64-S72. [PMID: 27569674 DOI: 10.1016/j.amjmed.2016.06.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The direct oral anticoagulants (DOACs) provide a number of clinical advantages over vitamin K antagonists for the treatment of thromboembolism, including improved efficacy and safety, as well as no need for regular monitoring of anticoagulant effect. However, as with all anticoagulants, bleeding complications may occur, and anticoagulant reversal may be required in specific clinical situations, such as in patients experiencing spontaneous or traumatic bleeds, or in anticoagulated patients requiring emergency surgery or other invasive procedures. Therefore, several reversal agents for the DOACs are in development. This includes the specific reversal agent idarucizumab, which has been approved by the U.S. Food and Drug Administration and the European Medicines Agency for use in patients treated with dabigatran when urgent reversal of its anticoagulant effects is needed. Idarucizumab is a humanized monoclonal antibody fragment that binds with high affinity to free and thrombin-bound dabigatran, resulting in an almost irreversibly bound idarucizumab-dabigatran complex and thereby neutralizing dabigatran's anticoagulant activity. The reversal of the anticoagulant effects of dabigatran by idarucizumab has been demonstrated in animal bleeding models, in healthy volunteers with a range of ages and renal function, and in anticoagulated patients. In the phase 1 trials, at doses of 2 g or greater, idarucizumab resulted in immediate and complete reversal of the dabigatran anticoagulant effects and was well tolerated. In the absence of dabigatran, idarucizumab showed no effect on coagulation parameters or thrombin formation. These findings provide initial evidence that idarucizumab could provide a safe and effective means of reversing anticoagulant activity in patients treated with dabigatran in need of emergency surgery or in emergency bleeding situations.
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Idarucizumab, a specific reversal agent for dabigatran: mode of action, pharmacokinetics and pharmacodynamics, and safety and efficacy in phase 1 subjects. Am J Emerg Med 2016; 34:26-32. [DOI: 10.1016/j.ajem.2016.09.050] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Eikelboom J, Merli G. Bleeding with direct oral anticoagulants vs warfarin: clinical experience. Am J Emerg Med 2016; 34:3-8. [PMID: 27697439 DOI: 10.1016/j.ajem.2016.09.046] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The risk of bleeding in the setting of anticoagulant therapy continues to be re-evaluated following the introduction of a new generation of direct oral anticoagulants (DOACs). Interruption of DOAC therapy and supportive care may be sufficient for the management of patients who present with mild or moderate bleeding, but in those with life-threatening bleeding, a specific reversal agent is desirable. We review the phase 3 clinical studies of dabigatran, rivaroxaban, apixaban, and edoxaban in patients with nonvalvular atrial fibrillation, in the context of bleeding risk and management.
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Affiliation(s)
- John Eikelboom
- Department of Medicine, Division of Hematology and Thromboembolism, McMaster University, Hamilton, Ont, Canada.
| | - Geno Merli
- Departments of Surgery and Medicine, Jefferson Vascular Center, Thomas Jefferson University Hospitals, Philadelphia, PA
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38
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Abstract
The vitamin K antagonists (VKAs) have been the standard (and only) oral anticoagulants used for the long-term treatment or prevention of venous thromboembolism or stroke in patients with atrial fibrillation. The coagulopathy induced by VKAs can be reversed with vitamin K, and in urgent situations, the vitamin K-dependent coagulation factors can be replaced by transfusion. In the last decade, a new class of oral anticoagulants has been developed, direct oral anticoagulants that bind to a specific coagulation factor and neutralize it. These compounds were shown to be effective and safe compared with the VKAs and were licensed for specific indications, but without a specific reversal agent. The absence of a reversal agent is a barrier to more widespread use of these agents. Currently, for the management of major life-threatening bleeding with the direct oral anticoagulants, most authorities recommend the use of four factor prothrombin complex concentrates. There are now three reversal agents in development and poised to enter the market. Idarucizumab is a specific antidote targeted to reverse the direct thrombin inhibitor, dabigatran, which was recently approved for use in the USA. Andexanet alfa is an antidote targeted to reverse the oral direct factor Xa inhibitors as well as the indirect inhibitor enoxaparin. Ciraparantag is an antidote targeted to reverse the direct thrombin and factor Xa inhibitors as well as the indirect inhibitor enoxaparin.
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Grottke O, Aisenberg J, Bernstein R, Goldstein P, Huisman MV, Jamieson DG, Levy JH, Pollack CV, Spyropoulos AC, Steiner T, Del Zoppo GJ, Eikelboom J. Efficacy of prothrombin complex concentrates for the emergency reversal of dabigatran-induced anticoagulation. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2016; 20:115. [PMID: 27125504 PMCID: PMC4850655 DOI: 10.1186/s13054-016-1275-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Dabigatran is effective in decreasing the risk of ischaemic stroke in patients with atrial fibrillation. However, like all anticoagulants, it is associated with a risk of bleeding. In cases of trauma or emergency surgery, emergency reversal of dabigatran-induced anticoagulation may be required. A specific reversal agent for dabigatran, idarucizumab, has been approved by the US Food and Drug Administration. Alternative reversal agents are available, such as prothrombin complex concentrates (PCCs) and activated PCCs (aPCCs). In this review we evaluate the role of PCCs and aPCCs in the reversal of dabigatran anticoagulation and consider which tests are appropriate for monitoring coagulation in this setting. Pre-clinical studies, small clinical studies and case reports indicate that PCCs and aPCCs may be able to reverse dabigatran-induced anticoagulation in a dose-dependent manner. However, dosing based on coagulation parameters can be difficult because available assays may not provide adequate sensitivity and specificity for measuring anticoagulation induced by dabigatran or the countering effects of PCCs/aPCCs. In addition, PCCs or aPCCs can potentially provoke thromboembolic complications. Despite these limitations and the fact that PCCs and aPCCs are not yet licensed for dabigatran reversal, their use appears to be warranted in patients with life-threatening haemorrhage if idarucizumab is not available.
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Affiliation(s)
- Oliver Grottke
- Department of Anesthesiology, RWTH Aachen University Hospital, Pauwelsstrasse 30, 52074, Aachen, Germany.
| | - James Aisenberg
- The Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Richard Bernstein
- Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Patrick Goldstein
- Emergency Department and SAMU, Lille University Hospital, Lille, France
| | - Menno V Huisman
- Department of Thrombosis and Hemostasis, Leiden University Medical Center, Leiden, The Netherlands
| | - Dara G Jamieson
- Department of Neurology, Weill Cornell Medical College, New York, NY, USA
| | - Jerrold H Levy
- Department of Anesthesiology, Duke University School of Medicine, Durham, NC, USA
| | - Charles V Pollack
- Department of Emergency Medicine, Thomas Jefferson University, Philadelphia, PA, USA
| | - Alex C Spyropoulos
- Hofstra North Shore/LIJ School of Medicine, Lenox Hill Hospital, New York, NY, USA
| | | | - Gregory J Del Zoppo
- Departments of Medicine and Neurology, University of Washington, Seattle, WA, USA
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