Emergency reversal of pentasaccharide anticoagulants: a systematic review of the literature

Management of severe peri-operative bleeding: Guidelines from the European Society of Anaesthesiology and Intensive Care: Second update 2022

BACKGROUND

Management of peri-operative bleeding is complex and involves multiple assessment tools and strategies to ensure optimal patient care with the goal of reducing morbidity and mortality. These updated guidelines from the European Society of Anaesthesiology and Intensive Care (ESAIC) aim to provide an evidence-based set of recommendations for healthcare professionals to help ensure improved clinical management.

DESIGN

A systematic literature search from 2015 to 2021 of several electronic databases was performed without language restrictions. Grading of Recommendations, Assessment, Development and Evaluation (GRADE) was used to assess the methodological quality of the included studies and to formulate recommendations. A Delphi methodology was used to prepare a clinical practice guideline.

RESULTS

These searches identified 137 999 articles. All articles were assessed, and the existing 2017 guidelines were revised to incorporate new evidence. Sixteen recommendations derived from the systematic literature search, and four clinical guidances retained from previous ESAIC guidelines were formulated. Using the Delphi process on 253 sentences of guidance, strong consensus (>90% agreement) was achieved in 97% and consensus (75 to 90% agreement) in 3%.

DISCUSSION

Peri-operative bleeding management encompasses the patient's journey from the pre-operative state through the postoperative period. Along this journey, many features of the patient's pre-operative coagulation status, underlying comorbidities, general health and the procedures that they are undergoing need to be taken into account. Due to the many important aspects in peri-operative nontrauma bleeding management, guidance as to how best approach and treat each individual patient are key. Understanding which therapeutic approaches are most valuable at each timepoint can only enhance patient care, ensuring the best outcomes by reducing blood loss and, therefore, overall morbidity and mortality.

CONCLUSION

All healthcare professionals involved in the management of patients at risk for surgical bleeding should be aware of the current therapeutic options and approaches that are available to them. These guidelines aim to provide specific guidance for bleeding management in a variety of clinical situations.

When Will Fondaparinux Induce Thrombocytopenia?

The pentasaccharide Fondaparinux, a synthetic selective factor Xa inhibitor, is one of the safest anticoagulants in the heparin family that is recommended as an alternative drug for patients with hypersensitivity to other drugs such as heparin-induced thrombocytopenia (HIT). However, some observations of Fondaparinux-induced thrombocytopenia (FIT) have been reported while others claimed that FIT does not occur in patients with fondaparinux therapy, indicating that the mechanism of FIT remains controversial. Here, we utilized different methodologies including dynamic light scattering, immunosorbent and platelet aggregation assays, confocal laser scanning microscopy, and flow cytometry to gain insights into FIT. We found that at a certain concentration, Fondaparinux formed sufficient large and stable complexes with PF4 that facilitated binding of the HIT-like monoclonal KKO antibody and enhanced platelet aggregation and activation. We proposed a model to describe the role of Fondaparinux concentration in the formation of complexes with platelet factor 4 and how it promotes the binding of KKO. Our results clarify controversial observations of FIT in patients as each contains a dissimilar PF4:Fondaparinux concentration ratio.

Reversing anticoagulation in the hemorrhaging patient

PURPOSE OF REVIEW

Anticoagulants in general, but especially the relatively new direct oral anticoagulants and platelet inhibitors, pose a great challenge for physicians in the hemorrhaging patient. The aim of the present review is to provide an overview on recent studies dealing with the reversal of anticoagulation in the hemorrhaging patient and to describe our therapeutic emergency strategy for those patients.

RECENT FINDINGS

A specific antidote for dabigatran is already on the market and antidotes for the direct and indirect factor Xa inhibitors are in development. Moreover, bleeding under platelet inhibitors remains critical with very little evidence on effective reversal strategies.

SUMMARY

To reverse anticoagulation in the hemorrhaging patient, specific antidotes should be the first option if available, followed by four-factor prothrombin complex concentrate (PCC), activated PCC and recombinant activated factor seven as the emergency strategy. Fibrinogen concentrate, antifibrinolytics and oral charcoal, respectively, can be considered as an additional measure. Massive blood loss and thrombocytopenia should be treated independently according to the respective, local guidelines for (massive) transfusion of blood and blood products.

Position paper of the Italian Society of Internal Medicine (SIMI) on prophylaxis and treatment of venous thromboembolism in patients with cancer

Cancer patients are at high risk of developing thrombotic events, including venous thromboembolism (VTE) [deep venous thrombosis (DVT) and pulmonary embolism (PE)], and arterial thrombosis. DVT and PE represent the second leading cause of death in cancer patients; moreover, the development of thromboembolic events in cancer patients is linked to a greater need of hospitalization and frequency of side effects during treatment, in particular bleeding, and to an increased risk of recurrence during and following antithrombotic therapy. The thromboembolic risk may be different in different subgroups of cancer population, being highest in patients with metastatic disease, patients with pancreas, stomach, kidney or primary brain cancer, or during therapeutic interventions or surgery. This document focuses on several relevant topics including the epidemiology and pathogenesis of cancer-associated VTE, the current and future strategies of primary prevention and anticoagulant treatment, and the management of bleeding complications. The main literature data are discussed in detail, including, when available, evidence from randomized clinical trials and meta-analyses, international guidelines statements, the results of recently published trials comparing direct oral anticoagulants to low molecular weight heparin, and the design and aims of ongoing trials on prevention/treatment of cancer-associated VTE.

Pediatric Cardiac Intensive Care Society 2014 Consensus Statement: Pharmacotherapies in Cardiac Critical Care Anticoagulation and Thrombolysis

OBJECTIVE

Thrombotic complications are increasingly being recognized as a significant cause of morbidity and mortality in pediatric and congenital heart disease. The objective of this article is to review the medications currently available to prevent and treat such complications.

DATA SOURCES

Online searches were conducted using PubMed.

STUDY SELECTION

Studies were selected for inclusion based on their scientific merit and applicability to the pediatric cardiac population.

DATA EXTRACTION

Pertinent information from each selected study or scientific review was extracted for inclusion.

DATA SYNTHESIS

Four classes of medications were identified as potentially beneficial in this patient group: anticoagulants, antiplatelet agents, thrombolytic agents, and novel oral anticoagulants. Data on each class of medication were synthesized into the follow sections: mechanism of action, pharmacokinetics, dosing, monitoring, reversal, considerations for use, and evidence to support.

CONCLUSIONS

Anticoagulants, antiplatelet agents, and thrombolytic agents are routinely used successfully in the pediatric patient with heart disease for the prevention and treatment of a wide range of thrombotic complications. Although the novel oral anticoagulants have been approved for a limited number of indications in adults, studies on the safety and efficacy of these agents in children are pending.

Guidance for the practical management of the heparin anticoagulants in the treatment of venous thromboembolism

Venous thromboembolism (VTE) is a serious and often fatal medical condition with an increasing incidence. Despite the changing landscape of VTE treatment with the introduction of the new direct oral anticoagulants many uncertainties remain regarding the optimal use of traditional parenteral agents. This manuscript, initiated by the Anticoagulation Forum, provides clinical guidance based on existing guidelines and consensus expert opinion where guidelines are lacking. This specific chapter addresses the practical management of heparins including low molecular weight heparins and fondaparinux. For each anticoagulant a list of the most common practice related questions were created. Each question was addressed using a brief focused literature review followed by a multidisciplinary consensus guidance recommendation. Issues addressed included initial anticoagulant dosing recommendations, recommended baseline laboratory monitoring, managing dose adjustments, evidence to support a relationship between laboratory tests and meaningful clinical outcomes, special patient populations including extremes of weight and renal impairment, duration of necessary parenteral therapy during the transition to oral therapy, candidates for outpatient treatment where appropriate and management of over-anticoagulation and adverse effects including bleeding and heparin induced thrombocytopenia. This article concludes with a concise table of clinical management questions and guidance recommendations to provide a quick reference for the practical management of heparin, low molecular weight heparin and fondaparinux.

Treatment of acute subdural hematoma

OPINION STATEMENT

Clinical presentation, neurologic condition, and imaging findings are the key components in establishing a treatment plan for acute SDH. Location and size of the SDH and presence of midline shift can rapidly be determined by computed tomography of the head. Immediate laboratory work up must include PT, PTT, INR, and platelet count. Presence of a coagulopathy or bleeding diathesis requires immediate reversal and treatment with the appropriate agent(s), in order to lessen the risk of hematoma expansion. Reversal protocols used are similar to those for intracerebral hemorrhage, with institutional variations. Immediate neurosurgical evaluation is sought in order to determine whether the SDH warrants surgical evacuation. Urgent or emergent surgical evacuation of a SDH is largely influenced by neurologic examination, imaging characteristics, and presence of mass effect or elevated intracranial pressure. Generally, evacuation of an acute SDH is recommended if the clot thickness exceeds 10 mm or the midline shift is greater than 5 mm, regardless of the neurologic condition. In patients with patients with an acute SDH with clot thickness <10 mm and midline shift <5 mm, specific considerations of neurologic findings and clinical circumstances will be of importance. In addition, consideration will be given as to whether an individual patient is likely to benefit from surgery. For an acute SDH, evacuation by craniotomy or craniectomy is preferred over burr holes based on available data. Postoperative care includes monitoring of resolution of pneumocephalus, mobilization and drain removal, and monitoring for signs of SDH reaccumulation. Medical considerations include seizure prophylaxis and management as well as management and resumption of antithrombotic and anticoagulant medication.

Coagulopathies in the PICU: DIC and liver disease

Bleeding in patients in pediatric intensive care units is associated with an increased risk of mortality. Fortunately, most patients with an abnormal coagulation profile do not bleed because this is generally secondary to liver disease or dietary-induced vitamin K deficiency. When the laboratory markers of coagulopathy are the result of disseminated intravascular coagulation, bleeding is common and the risk of mortality extreme. Although interventions directed toward correcting the abnormal coagulation test results are generally initiated, they are also generally either not warranted or not fully successful.

A chemically-modified inactive antithrombin as a potent antagonist of fondaparinux and heparin anticoagulant activity

BACKGROUND

Heparin and its analogs, mediating their anticoagulant activity through antithrombin (AT) activation, remain largely used for the preventive and curative treatment of thrombosis. The major adverse reaction of these drugs is the bleeding risk associated with overdose. Unfractionnated heparin (UFH) can be efficiently and rapidly neutralized by protamine sulfate, but this reversal partially neutralizes low-molecular-weight heparin (LMWH) and is inefficient in reversing fondaparinux. To secure administration of AT-mediated anticoagulants and counteract bleeding disorders, we previously designed a recombinant inactive AT as an antidote to heparin derivatives.

OBJECTIVES

To get around the limited production level of recombinant AT, we propose in this study an alternative strategy to produce a chemically modified inactive AT, exhibiting increased heparin affinity, as an antagonist of heparin analogs.

METHODS

Plasma-derived AT was chemically modified with 2,3 butanedione, a diketone known to specifically react with the arginine side chain. The chemical reaction was conducted in the presence of heparin to preserve basic residues within the heparin binding site from modifications.

RESULTS

AT treated by butanedione and selected for its high heparin affinity (AT-BD) was indeed modified on reactive Arg393 and thus exhibited decreased anticoagulant activity and increased heparin affinity. AT-BD was able to neutralize anticoagulant activity of heparin derivatives in vitro and in vivo and was devoid of intrinsic anticoagulant activity, as assessed by activated partial thromboplastin time assay.

CONCLUSIONS

AT-BD appears to be as efficient as protamine to neutralize UFH in vivo but could be more largely used because it also reverses fondaparinux and LMWH.

Contemporary Anticoagulation Reversal Focus on Direct Thrombin Inhibitors and Factor Xa Inhibitors

Several oral direct thrombin inhibitors (DTIs) and factor Xa (FXa) inhibitors have recent Food and Drug Administration approval or are under investigation in late-stage clinical trials for the prevention and treatment of thromboembolic events. Rapid reversal of anticoagulation is typically recommended in patients with severe or life-threatening bleeding and in patients requiring surgery or invasive procedures. However, no antidote exists for DTIs or FXa inhibitors though replacement of coagulation factors using clotting factor concentrates is routinely considered in some clinical scenarios. Clotting factor concentrates available in the United States include prothrombin complex concentrate, activated prothrombin complex concentrate, and recombinant factor VII, activated. Coagulation tests to confirm adequate reversal of anticoagulation should be considered and commonly include activated partial thromboplastin time and thrombin time (TT) for DTIs, and chromogenic FXa assay and TT for FXa inhibitors. Monitoring of coagulation tests should continue for 1 to 2 days after achievement of hemostasis, since the duration of the clotting factor concentrate may be shorter than the oral anticoagulant, especially in patients with organ dysfunction. Utilization of decision-support tools and use of standardized reversal protocols are recommended to prevent errors in prescribing and dispensing for clotting factor concentrates.