Reversal of Vitamin K Antagonist (VKA) effect in patients with severe bleeding: a French multicenter observational study (Optiplex) assessing the use of Prothrombin Complex Concentrate (PCC) in current clinical practice

Management of major bleeding for anticoagulated patients in the Emergency Department: an European experts consensus statement

An increasing number of patients presenting to the emergency department (ED) with life-threatening bleeding are using oral anticoagulants, such as warfarin, Factor IIa and Factor Xa inhibitors. Achieving rapid and controlled haemostasis is critically important to save the patient's life. This multidisciplinary consensus paper provides a systematic and pragmatic approach to the management of anticoagulated patients with severe bleeding at the ED. Repletion and reversal management of the specific anticoagulants is described in detail. For patients on vitamin K antagonists, the administration of vitamin K and repletion of clotting factors with four-factor prothrombin complex concentrate provides real-time ability to stop the bleeding. For patients using a direct oral anticoagulant, specific antidotes are necessary to reverse the anticoagulative effect. For patients receiving the thrombin inhibitor dabigatran, treatment with idarucizamab has been demonstrated to reverse the hypocoagulable state. For patients receiving a factor Xa inhibitor (apixaban or rivaroxaban), andexanet alfa is the indicated antidote in patients with major bleeding. Lastly, specific treatment strategies are discussed in patients using anticoagulants with major traumatic bleeding, intracranial haemorrhage or gastrointestinal bleeding.

Clinical Relevance of Preclinical and Clinical Studies of Four-Factor Prothrombin Complex Concentrate for Treatment of Bleeding Related to Direct Oral Anticoagulants

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.

Detection and differentiation of active and inactive isoforms of coagulation factors II, VII, IX, and X in prothrombin complex concentrate by mass spectrometry

PURPOSE

Prothrombin complex concentrates (PCCs) are plasma products containing a mixture of four inactive/proactive coagulation factors. The activated forms of human coagulation factors, like Thrombin (FIIa), Convertin (FVIIa), activated Christmas factor (FIXa) and the activated Stuart-Prower factor (FXa), are impurities in PCCs. Until now no valid assay exists to differentiate the non activated proform (inactive) from active coagulation factor isoforms in PCCs in one measurement. Therefore, the aim of this study was to establish a mass spectrometry (LC-MS/MS)-based assay to address this issue in the ready to use medicinal product.

METHODS

Bottom-up proteomics combining double digestion (Glu-C & Lys-C) and LC-MS/MS, was used to differentiate the inactive and active forms of the coagulation factors Prothrombin (FII), Proconvertin (FVII), Christmas factor (FIX) and the Stuart-Prower-factor (FX) in PCCs.

RESULTS AND CONCLUSIONS

A targeted pseudo-multiple reaction monitoring (pMRM-LC-MS/MS)-assay was developed for the specific detection of four different coagulation factors in PCCs. Proteotypic peptides for the inactive/active isoforms (zymogen) of the four coagulation factors were identified and validated by the investigation of six investigational and one commercially available PCCs. In conclusion, the semi-quantitative determination and the distinction between the active and the inactive isoform of the respective coagulation factors were possible in one liquid chromatography tandem mass spectrometry (LC-MS/MS) run.

A European consensus statement on the use of four-factor prothrombin complex concentrate for cardiac and non-cardiac surgical patients

Modern four-factor prothrombin complex concentrate was designed originally for rapid targeted replacement of the coagulation factors II, VII, IX and X. Dosing strategies for the approved indication of vitamin K antagonist-related bleeding vary greatly. They include INR and bodyweight-related protocols as well as fixed dose regimens. Particularly in the massively bleeding trauma and cardiac surgery patient, four-factor prothrombin complex concentrate is used increasingly for haemostatic resuscitation. Members of the Transfusion and Haemostasis Subcommittee of the European Association of Cardiothoracic Anaesthesiology performed a systematic literature review on four-factor prothrombin complex concentrate. The available evidence has been summarised for dosing, efficacy, drug safety and monitoring strategies in different scenarios. Whereas there is evidence for the efficacy of four-factor prothrombin concentrate for a variety of bleeding scenarios, convincing safety data are clearly missing. In the massively bleeding patient with coagulopathy, our group recommends the administration of an initial bolus of 25 IU.kg^-1 . This applies for: the acute reversal of vitamin K antagonist therapy; haemostatic resuscitation, particularly in trauma; and the reversal of direct oral anticoagulants when no specific antidote is available. In patients with a high risk for thromboembolic complications, e.g. cardiac surgery, the administration of an initial half-dose bolus (12.5 IU.kg^-1 ) should be considered. A second bolus may be indicated if coagulopathy and microvascular bleeding persists and other reasons for bleeding are largely ruled out. Tissue-factor-activated, factor VII-dependent and heparin insensitive point-of-care tests may be used for peri-operative monitoring and guiding of prothrombin complex concentrate therapy.

Management of direct factor Xa inhibitor-related major bleeding with prothrombin complex concentrate: a meta-analysis

A targeted antidote for reversal of direct factor Xa (FXa) inhibitors is now available for clinical use in the United States, but it is costly and has limited availability. In a systematic review, we evaluated the safety and effectiveness of 4-factor prothrombin complex concentrate (4F-PCC) as an alternative for managing direct FXa inhibitor-related major bleeding. A systematic literature search was conducted using Medline, Embase, and the Cochrane Register of Controlled Trials up to September 2018. No comparative studies were found. Ten case series with 340 patients who received PCC for direct FXa inhibitor-related major bleeding were included. The pooled proportion of patients with effective management of major bleeding was 0.69 (95% confidence interval [CI], 0.61-0.76) in 2 studies using the International Society on Thrombosis and Haemostasis (ISTH) criteria and 0.77 (95% CI, 0.63-0.92) in 8 studies that did not use the ISTH criteria; all-cause mortality was 0.16 (95% CI, 0.07-0.26), and thromboembolism rate was 0.04 (95% CI, 0.01-0.08). On the basis of evidence with very low certainty from single-arm case series, it is difficult to determine whether 4F-PCC in addition to cessation of direct oral FXa inhibitor is more effective than cessation of direct oral FXa inhibitor alone in patients with direct FXa inhibitor-related major bleeding.

Prothrombin complex concentrate for vitamin K antagonist reversal in acute bleeding settings: efficacy and safety

Introduction: Current guidelines recommend the administration of prothrombin complex concentrate in combination with vitamin K for normalization of coagulation in patients presenting with vitamin K antagonist-associated major bleeding, but until recently no adequately powered comparative trials had been conducted to support these recommendations. In this article, the authors review the evidence from studies assessing prothrombin complex concentrate treatment in these patients. Areas covered: A PubMed search (spanning January 1900 to September 2018) was conducted using the following search terms: prothrombin complex concentrate* AND (warfarin or (vitamin K antagonist*)), and papers relevant to major hemorrhagic events were identified; results from studies that used a randomized controlled trial (RCT) or a prospective design are presented here. Overall, the identified studies support the current guideline recommendations and indicate that prothrombin complex concentrates have at least similar safety profiles to other treatment options, such as fresh frozen plasma and recombinant activated factor VII. Expert opinion: It is hoped that the results from studies discussed here will inform future guideline updates; however, local clinical practice may also occasionally act as a barrier to adoption of guideline recommendations. There is an urgent need for further RCTs/prospective trials directly comparing PCC and plasma administration in acute bleeding settings.

Is Coagulopathy an Appropriate Therapeutic Target During Critical Illness Such as Trauma or Sepsis?

Coagulopathy is a common and vexing clinical problem in critically ill patients. Recently, major advances focused on the treatment of coagulopathy in trauma and sepsis have emerged. However, the targeting of coagulopathy with blood product transfusion and drugs directed at attenuating the physiologic response to these conditions has major potential risk to the patient. Therefore, the identification of coagulopathy as a clinical target is an area of uncertainty and controversy. To analyze the state of the science regarding coagulopathy in critical illness, a symposium addressing the problem was organized at the 39th annual meeting of the Shock Society in the summer of 2016. This manuscript synthesizes the viewpoints of the four expert panelists at the debate and presents an overview of the potential positive and negative consequences of targeting coagulopathy in trauma and sepsis.

Benefits and harms of 4-factor prothrombin complex concentrate for reversal of vitamin K antagonist associated bleeding: a systematic review and meta-analysis

Prothrombin complex concentrate (PCC) is used for reversal of vitamin K antagonists (VKA) in patients with bleeding complications. This study aims to assess benefits and harms of 4-factor PCC compared to fresh frozen plasma (FFP) or no treatment in VKA associated bleeding. PubMed, EMBASE and CENTRAL were searched from 1945 to August 2015. Studies reporting 4-factor PCC use for VKA associated bleeding and providing data on INR normalization, mortality or thromboembolic (TE) complications were eligible. Two authors screened titles and full articles for inclusion, extracted data, and assessed risk of bias. Mortality data were pooled using Mantel–Haenszel random effects meta-analysis. Nineteen studies were included (N = 2878); 18 cohort studies and one RCT. Six studies had good methodological quality, 9 moderate and 4 poor. Baseline INR values ranged from 2.2 to >20. The INR within 1 h after PCC administration ranged from 1.4 to 1.9, and after FFP administration from 2.2 to 12. PCC reduced the time to reach INR correction in comparison with FFP or no treatment. The observed mortality rate ranged from 0 to 43% (mean 17%) in the PCC, 4.8–54% (mean 16%) in the FFP and 23–69% (mean 51%) in the no treatment group. Meta-analysis of mortality data resulted in an OR of 0.64 (95% confidence interval [CI] 0.27–1.5) for PCC versus FFP and an OR 0.41 (95% CI 0.13–1.3) for PCC versus no treatment. TE complications were observed in 0–18% (mean 2.5%) of PCC and in 6.4% of FFP recipients. Four-factor PCC is an effective and safe option in reversal of VKA bleeding events.

Vitamin K antagonists and emergencies

The recent emergence of 'non-VKA' oral anticoagulants may have led to some forgetting that vitamin K antagonists (VKA) are by far the most widely prescribed oral anticoagulants worldwide. Consequently, we decided to summarize the information available on them. This paper presents the problems facing emergency physicians confronted with patients on VKAs in 10 points, from pharmacological data to emergency management. Vitamin K antagonists remain preferable in many situations including in the elderly, in patients with extreme body weights, severe chronic kidney or liver disease or valvular heart disease, and in patients taking VKAs with well-controlled international normalized ratios (INRs). Given the way VKAs work, a stable anticoagulant state can only be achieved at the earliest 5 days after starting therapy. The induction phase of VKA treatment is associated with the highest risk of bleeding; validated algorithms based on INR values have to be followed. VKA asymptomatic overdoses and 'non-severe' hemorrhage are managed by omitting a dose or stopping treatment plus administering vitamin K depending on the INR. Major bleeding is managed using a VKA reversal strategy. A prothrombin complex concentrate infusion plus vitamin K is preferred to rapidly achieve an INR of up to 1.5 and maintain a normal coagulation profile. The INR must be measured 30 min after the infusion. Before an invasive procedure, if an INR of less than 1.5 (<1.3 in neurosurgery) is required, it can be achieved by combining prothrombin complex concentrate and vitamin K. A well-codified strategy is essential for managing patients requiring emergency invasive procedures or presenting bleeding complications.

Current evidence of oral anticoagulant reversal: A systematic review

INTRODUCTION

Approximately 4-6% of patients treated with oral anticoagulants (OAC) will suffer from major hemorrhage or be in need of urgent surgery necessitating anticoagulant reversal therapy. Several new oral anticoagulants and reversal agents have been introduced that make it difficult for physicians to stay updated on the current evidence of reversal management. This study aims to review the recent literature on oral anticoagulation reversal therapy and to present the current evidence in an easily approachable manner.

MATERIALS AND METHODS

A systematic literature search was conducted using PubMed and EMBASE to identify the latest publications on both vitamin K antagonist (VKA) and direct oral anticoagulant (DOAC) reversal strategies. All studies on humans who received any acute reversal management of VKA treatment were included, except case studies. Since only two studies on acute reversal of DOAC treatment have been published, clinical trials on healthy volunteers were also included.

RESULTS

Twenty-one studies with a total of 4783 VKA treated patients, and 12 studies with a total of 529 DOAC treated patients were included. Elevated INR values due to VKA treatment could be reversed (INR≤1.5) in 63.1% (95% CI: 61.0-65.2) of study subjects after treatment with 4F-PCC, as compared with 12.2% (95% CI: 8.2-16.2) after treatment with fresh frozen plasma (FFP), (p<0.001). Thromboembolism occurred in 1.6% (95% CI: 1.2-2.1) of VKA-patients treated with 4F-PCC, and in 4.5% (95% CI: 2.3-6.7) of FFP-treated patients. To date, reversal of laboratory parameters has been demonstrated for two reversal agents specific to DOACs: idarucizumab for dabigatran reversal and andexanet-alfa for factor Xa-inhibitor reversal.

CONCLUSIONS

This review supports the use of PCC for VKA reversal, specifically for 4F-PCC over FFP for laboratory reversal. There are no studies on clinical efficacy of non-specific agents for DOAC reversal and the evidence for laboratory reversal is not consistent.

Efficacy and Safety of Edoxaban in Nonvalvular Atrial Fibrillation: A Meta-analysis of Randomized Controlled Trials

GOALS

Edoxaban is a potential alternative to warfarin for preventing thromboembolism in atrial fibrillation. However, the efficacy and safety, and the optimal regimen of edoxaban are still controversial. This study compared the efficacy and safety of edoxaban and warfarin in nonvalvular atrial fibrillation, and the effects of different edoxaban dosages.

METHODS

A systematic search for randomized controlled trials comparing edoxaban with warfarin in nonvalvular atrial fibrillation was conducted using PubMed, EMBASE, and the Cochrane Library databases. The main measures and outcomes included efficacy end points (thromboembolic events and all-cause mortality) and safety end points (all bleeding events, major bleeding events, clinically relevant nonmajor bleeding, and minor bleeding).

RESULTS

Four studies including 23,001 patients were included in the meta-analysis. Edoxaban was noninferior to warfarin for preventing stroke and systemic embolism (risk ratio [RR] = 1.00; 95% confidence interval [CI], .88-1.13; Z = .01; P = .99). In safety analyses, edoxaban was superior to warfarin in terms of major bleeding, clinically relevant nonmajor bleeding, and minor bleeding (all P <.00001). In terms of optimal dosing, 30 mg/day edoxaban had a significantly lower risk of all bleeding (RR = .79; 95% CI, .75-.83; Z = 9.07; P <.00001) than 60 mg/day, but was inferior at preventing stroke and systemic embolism (RR = 1.31; 95% CI, 1.13-1.51; Z = 3.56; P = .0004).

CONCLUSIONS

Edoxaban was noninferior to warfarin in terms of efficacy and superior to warfarin in terms of safety. The benefits of edoxaban were related to the dose; efficacy was better at 60 mg/day, but there was lower risk of bleeding at 30 mg/day.

Forum for debate: Safety of allogeneic blood transfusion alternatives in the surgical/critically ill patient

In recent years, several safety alerts have questioned or restricted the use of some pharmacological alternatives to allogeneic blood transfusion in established indications. In contrast, there seems to be a promotion of other alternatives, based on blood products and/or antifibrinolytic drugs, which lack a solid scientific basis. The Multidisciplinary Autotransfusion Study Group and the Anemia Working Group España convened a multidisciplinary panel of 23 experts belonging to different healthcare areas in a forum for debate to: 1) analyze the different safety alerts referred to certain transfusion alternatives; 2) study the background leading to such alternatives, the evidence supporting them, and their consequences for everyday clinical practice, and 3) issue a weighted statement on the safety of each questioned transfusion alternative, according to its clinical use. The members of the forum maintained telematics contact for the exchange of information and the distribution of tasks, and a joint meeting was held where the conclusions on each of the items examined were presented and discussed. A first version of the document was drafted, and subjected to 4 rounds of review and updating until consensus was reached (unanimously in most cases). We present the final version of the document, approved by all panel members, and hope it will be useful for our colleagues.

Efficacy of the prothrombin complex concentrate prothromplex in patients requiring urgent reversal of vitamin K antagonists or presenting with uncontrolled bleeding: a retrospective, single center study

The objective of the present study was to investigate the efficacy of a four-factor prothrombin complex concentrate (Prothromplex, PTX) in shortening prolonged international normalized ratio or controlling life-threatening bleeding. The study was a retrospective single-centre study that included 142 patients treated with PTX and allocated in three groups: patients on vitamin K antagonists (VKA) (acenocumarol) and undergoing invasive procedure or presenting with severe bleeding (n = 76), patients treated with VKA presenting with intracranial haemorrhage (n = 22), and patients not on VKA and presenting with uncontrolled bleeding (n = 44). The primary outcome variable was international normalized ratio (INR) return to the norm after PTX infusion. Secondary outcome variables included bleeding control and reduction of transfusion rate. Overall, patients received a median of 1200 IU (≈15 IU/kg) of PTX, and INR decreased from 4 ± 3 to 1.7 ± 1.2 (P < 0.01) in all groups, although it remained at least 1.4 in 38% of patients (29.3% among patients receiving 25 IU/kg vs. 42.6% among those receiving 15 IU/kg; P < 0.05). Patients with initial INR at least 4 benefited the most from treatment. After PTX administration, there was a significant reduction in both transfused blood components units (P < 0.01) and estimated blood loss volume (from 1500 ± 1500 to 200 ± 100 ml; P < 0.01), and only one episode of deep venous thrombosis was observed. Administration of fixed doses of PTX shortened prolonged international normalized ratio and improved life-threatening bleeding in patients with or without VKA therapy. Higher dose attained a more adequate post-infusion INR.

Guideline-concordant administration of prothrombin complex concentrate and vitamin K is associated with decreased mortality in patients with severe bleeding under vitamin K antagonist treatment (EPAHK study)

Introduction

In vitamin K antagonist (VKA)-treated patients with severe hemorrhage, guidelines recommend prompt VKA reversal with prothrombin complex concentrate (PCC) and vitamin K. The aim of this observational cohort study was to evaluate the impact of guideline concordant administration of PCC and vitamin K on seven-day mortality.

Methods

Data from consecutive patients treated with PCC were prospectively collected in 44 emergency departments. Type of hemorrhage, coagulation parameters, type of treatment and seven-day mortality mortality were recorded. Guideline-concordant administration of PCC and vitamin K (GC-PCC-K) were defined by at least 20 IU/kg factor IX equivalent PCC and at least 5 mg of vitamin K performed within a predefined time frame of eight hours after admission. Multivariate analysis was used to assess the effect of appropriate reversal on seven-day mortality in all patients and in those with intracranial hemorrhage (ICH).

Results

Data from 822 VKA-treated patients with severe hemorrhage were collected over 14 months. Bleeding was gastrointestinal (32%), intracranial (32%), muscular (13%), and “other” (23%). In the whole cohort, seven-day mortality was 13% and 33% in patients with ICH. GC-PCC-K was performed in 38% of all patients and 44% of ICH patients. Multivariate analysis showed a two-fold decrease in seven-day mortality in patients with GC-PCC-K (odds ratio (OR) = 2.15 (1.20 to 3.88); P = 0.011); this mortality reduction was also observed when only ICH was considered (OR = 3.23 (1.53 to 6.79); P = 0.002).

Conclusions

Guideline-concordant VKA reversal with PCC and vitamin K within eight hours after admission was associated with a significant decrease in seven-day mortality.