2020 ACC Expert Consensus Decision Pathway on Management of Bleeding in Patients on Oral Anticoagulants

A review of the perioperative management of direct oral anticoagulants for pediatric anesthesiologists

BACKGROUND

Although direct oral anticoagulants (DOACs) have been used in the adult population for over a decade, DOACs use has begun to rise in pediatric populations since FDA approval of rivaroxaban and dabigatran, DOACs offer several advantages for pediatric patients, to other anticoagulants, including a similar safety profile, minimal lab monitoring, and ease of administration. The rise in DOAC use has led to an increasing number of pediatric patients managed on DOACs presenting for elective and urgent procedures. Perioperative management of anticoagulation is often challenging for providers due to the lack of expert consensus guidelines and the difficulty in balancing a patient's thrombotic risk with bleeding risk for a given procedure.

AIMS

Using the most up to date literature, we provide a focused review on the perioperative management of DOACs in pediatric patients.

CONCLUSIONS

This work presents a focused review for pediatric anesthesiologists on clinically available DOACs, perioperative monitoring and management of DOACs, as well as options and indications for reversal. While consensus expert practice guidelines are still needed, we hope this work will familiarize perioperative physicians with these agents, recommended uses, and potential perioperative management.

Pearls and Pitfalls in the Measurement of Direct Oral Anticoagulants

Due to their widespread use, testing for direct oral anticoagulants (DOACs) has become urgent in certain clinical situations. Screening based on widely available, rapid, and simple hemostasis assays such as prothrombin time, activated partial thromboplastin time, or even diluted Russel Viper venom time may provide sufficient evidence of "over-coagulation" and could be used "in small/peripheral/spoke laboratories" as an emergency strategy, but is not thought to be reliable for driving clinical decision making. Given their good correlation with plasma concentration, urine dipsticks may be considered a valuable alternative for emergency screening, although their performance is dependent on renal function, may vary depending on the time since the last urination, and there may be problems of interfacing with the laboratory/hospital information system. Separation methods based on liquid chromatography and mass spectrometry may be clinically questionable, since they measure the concentration rather than the actual inhibitory effect of DOACs, are relatively expensive, cumbersome and time consuming, and therefore seem unsuitable for most conditions requiring urgent clinical decision making. A proposed approach therefore involves establishing a network of routine clinical laboratories, designating a reference center where DOAC tests could be available 24/7, establishing a clear diagnostic care pathway for ordering the tests from the laboratory and standard operating procedures for performing them, the use of the diluted thrombin time for dabigatran and anti-FXa assays (drug-calibrated) for rivaroxaban, apixaban, and edoxaban, as well as providing expert advice throughout the testing process, from ordering to interpretation of results.

Prothrombin complex concentrate for direct factor Xa inhibitor-associated bleeding or before urgent surgery

INTRODUCTION

Factor Xa inhibitor (FXaI)-associated bleeding events are common and associated with substantial morbidity. Systematic evaluation of widely available, effective, and affordable FXaI bleed management strategies is needed.

MATERIALS AND METHODS

We conducted a single-center retrospective cohort study of FXaI-treated patients presenting to a tertiary academic medical center from January 2018 to May 2019 who received 25-50 IU/kg 4F-PCC for either FXaI-associated major bleeding or urgent surgery. The primary outcome was hemostatic efficacy, and the safety outcome was the 30-day risk of thromboembolism.

RESULTS

PCC was used to treat FXaI-associated bleeding in 83 cases (79.1 %) and was given before urgent surgery in 22 cases (20.9 %). Sixty-six patients were on apixaban, 38 were on rivaroxaban and one patient was on edoxaban. Intracranial hemorrhage (ICH) and gastrointestinal bleeding accounted for most bleeds (74.7 %). Median interval between last DOAC intake and presentation to triage was 9 h [IQR 5.3-14.8] and median PCC dosing was 40.0 IU/kg [IQR 28.5-46.6]. Forty-two patients (40.0 %) had pre-PCC FXaI levels drawn with median FXaI levels of 114.5 ng/mL [IQR 70.0-175.0]. Effective hemostasis occurred in 66.7 % [95%CI 55.4-76.3] of patients receiving PCC for bleeding and surgical hemostasis was rated as normal in 95.5 % (95%CI 76.5-100.0) for patients having urgent surgery. The 30-day risk of thromboembolism was 7.6 % [95%CI 3.7-14.5] and 22.9 % [95%CI 15.8-31.8] of patients died.

CONCLUSIONS

PCC for FXaI-associated bleeding was associated with hemostatic efficacy in two-thirds of patients and thromboembolic events were uncommon. PCC represents a promising treatment strategy for FXaI-associated bleeding.

3-Factor prothrombin complex concentrate versus 4-factor prothrombin complex concentrate for the reversal of oral factor Xa inhibitors

Multiple agents exist for the reversal of oral Factor Xa inhibitor (FXa) associated bleeding, including Coagulation FXa Recombinant, Inactivated zhzo (andexanet alfa) and 4-factor prothrombin complex concentrate (4F-PCC). While classified as a 3F-PCC product, Profilnine contains up to 35 IU of Factor VII (per 100 IU of Factor IX) in addition to therapeutic levels of Factors II, IX, and X, and has demonstrated a similar impact on prothrombin time and blood product usage in non-warfarin related bleeding. This was a retrospective, multicenter study at four medical centers of adult patients who presented with major bleeding associated with oral FXa inhibitors and received either 4F-PCC (n = 64) or 3F-PCC (n = 61). The primary outcome was hemostatic effectiveness. Secondary outcomes included the incidence of thromboembolism, in-hospital mortality, and length of stay. The most common indication for reversal was intracranial bleeding. For the primary outcome, 84% of all patients were rated as effective with no difference noted between the groups (p = 0.81). No significant difference between groups was found in the multivariable analysis adjusting for baseline differences between groups including race, total body weight, type of bleeding, and the use of antiplatelet therapy. There was no difference in the length of stay, in-hospital mortality, or the incidence of thromboembolism between the groups. Overall, no significant differences were found in the effectiveness or safety of 4F-PCC and 3F-PCC use in the management of oral FXa inhibitor-associated bleeding. Further investigations are warranted to explore the use of 3F-PCC for this indication and its safety and effectiveness.

[Management of anticoagulant-related soft tissue bleeding]

BACKGROUND AND OBJECTIVE

Spontaneous, severe, and life-threatening soft tissue bleeding (STB) in patients taking anticoagulants is associated with high morbidity and mortality due to the substantial blood loss and nonspecific clinical symptoms. The optimal management of these predominantly older patients with multiple comorbidities has not yet been unanimously clarified.

MATERIALS AND METHODS

This work comprises a literature search and analysis of the pertinent retrospective studies and case series.

RESULTS

Structured diagnostic workup with contrast-enhanced computed tomography (CT) is essential for planning transarterial embolization (TAE). Contrast agent extravasation, the signal flare phenomenon, and the hematocrit effect are all indicative of active bleeding or an anticoagulant-related hematoma. For TAE, coils, particles, and liquid embolic agents can be used alone or in combination. A back door/front door embolization should be strived for.

CONCLUSION

Transarterial embolization is the method of choice for managing anticoagulant-related localized or diffuse spontaneous soft tissue bleeding in the context of hemodynamic stabilization of the patient.

Modelling the effects of 4-factor prothrombin complex concentrate for the management of factor Xa-associated bleeding

The management of factor Xa (FXa) inhibitor-associated bleeding remains a clinical challenge. Massive bleeding is often associated with complex coagulopathy and, thus, the sole reversal of FXa inhibitors might not be sufficient to restore hemostasis, requiring instead a multimodal approach. Four-factor prothrombin complex concentrate (4F-PCC) is widely recognized as a viable treatment option for FXa inhibitor-associated bleeding. Here, we applied computational models to explore the effect 4F-PCC has on the coagulation cascade and restoration of thrombin generation in a system that simulates a patient that has received a FXa inhibitor. The coagulation model is largely based on a previously developed model with modifications incorporated from various other published sources. The model was calibrated and validated using data from a phase 3 clinical trial of vitamin K antagonist reversal with 4F-PCC. Using the parameters and initial conditions determined during the calibration and validation process, the prothrombin time (PT) test simulations predicted a PT of 11.4 seconds. The model successfully simulated the effects of rivaroxaban and apixaban on total thrombin concentration and showed that 4F-PCC increased thrombin generation in the presence of rivaroxaban or apixaban.

Effect of Vascular Senescence on the Efficacy and Safety of Warfarin: Insights from Rat Models and a Prospective Cohort Study

Warfarin, with its narrow therapeutic range, requires the understanding of various influencing factors for personalized medication. Vascular senescence, marked by vascular stiffening and endothelial dysfunction, has an unclear effect on the efficacy and safety of warfarin. Based on previous studies, we hypothesized that vascular senescence increases the risk of bleeding during warfarin therapy. This study aimed to explore these effects using animal models and clinical cohorts. We established rat models of vascular senescence and calcification using d-galactose, vitamin D, and nicotine. After validating the models, we examined changes in the international normalized ratio (INR) at fixed warfarin doses (0.20 and 0.35 mg/kg). We found that vascular senescence caused significantly elevated INR values and increased bleeding risk. In the prospective clinical cohort study (NCT06428110), hospitalized warfarin patients with standard dose adjustments were divided into vascular senescence and control groups based on ultrasound and computed tomography diagnosis. Using propensity score matching to exclude the influence of confounding factors, we found that the vascular senescence group had lower steady-state warfarin doses and larger dose adjustments, with a higher probability of INR exceeding the therapeutic range. The vascular senescence group tended to experience more bleeding or thromboembolic/ischemic events during 1 year of follow-up, while there was no statistical difference. In conclusion, vascular senescence leads to unstable INR values and increases higher bleeding risk during warfarin therapy, highlighting the importance of considering vascular senescence in future precision warfarin therapies. SIGNIFICANCE STATEMENT: Many factors influence warfarin efficacy; however, the effect of vascular senescence remains unclear. This study aimed to investigate the effects of vascular senescence on the efficacy and safety of warfarin. Through both rat models and clinical cohort studies, our findings indicated that vascular senescence may compromise the stability of warfarin, presenting challenges in maintaining its efficacy and safety.

Facial trauma with life-threatening bleeding treated by andexanet alfa administration: A case report

Recently, anticoagulant reversal has become a treatment option for life-threatening bleeding, especially in intracranial hemorrhage. Although evidence of the beneficial efficacy of andexanet alfa accumulates in cases of intracranial hemorrhage, little is known about its effectiveness in head injuries without intracranial hemorrhage. We present the case of an 87-year-old man who suffered a stroke 1 year previously and had been taking apixaban since then, who was brought to the emergency department with facial trauma due to a fall. Upon arrival at the hospital, the patient was conscious, and his vital signs were normal; however, physical examination revealed epistaxis, and plain head computed tomography (CT) showed multiple facial fractures without intracranial hemorrhage. As epistaxis was challenging to control, upper airway obstruction developed. His percutaneous oxygen saturation (SpO2) decreased rapidly, and he underwent tracheal intubation. Contrast-enhanced head CT revealed at least two extravasations, near the anterior wall of the right maxillary sinus and from the nasal canal to the nasopharynx area. However, embolization using interventional radiology was deemed difficult. Because the bleeding did not stop, we determined the bleeding was life-threatening and uncontrollable. Therefore, we infused andexanet alfa to stop the bleeding. After infusion, hemostasis was confirmed. This case suggests the effectiveness of andexanet alfa in cases of facial trauma and extracranial bleeding difficult to stop, resulting in favorable outcomes and hemostatic effects.

In factor Xa inhibitor-related acute ICH, andexanet vs. usual care improved hemostatic efficacy but increased thrombotic events

SOURCE CITATION

Connolly SJ, Sharma M, Cohen AT, et al; ANNEXA-I Investigators. Andexanet for factor Xa inhibitor-associated acute intracerebral hemorrhage. N Engl J Med. 2024;390:1745-1755. 38749032.

Utility of thromboelastography to assess the effect of anticoagulation reversal in intracranial hemorrhage

Background

Intracranial hemorrhage (ICH) is a serious complication associated with oral anticoagulant use and is associated with significant morbidity and mortality. Although anticoagulation reversal agents are utilized as standard of care, practitioners are limited in their ability to assess degree of anticoagulation reversal for direct oral anticoagulants (DOACs). There is a clinical need identify biomarkers to assess anticoagulation status in patients with DOAC-associated ICH to ensure hemostatic efficacy of anticoagulation reversal agents in the acute setting. The purpose of this study was to assess the utility of thromboelastography (TEG) to assess the impact of anticoagulation reversal in patients presenting to the emergency department (ED) with DOAC-associated ICH.

Methods

We conducted a prospective, observational cohort study in adult patients presenting to the ED with acute DOAC-associated ICH. Patients were excluded if last DOAC dose was >48 hours prior to hospital arrival, if they experienced polytrauma, were pregnant, incarcerated, had a history of hepatic failure or coagulopathy, or received anticoagulation reversal with products other than prothrombin complex concentrates (PCCs). We collected baseline TEG samples from participants prior to anticoagulation reversal, as well as 30-minutes, 12-hours, and 24-hours post-reversal. TEG samples were also collected from participants who transferred to our facility after reversal at ED presentation, as well as 12- and 24-hours post-reversal.

Results

Pre-reversal TEG was collected on 10 participants prior to DOAC reversal. A significant decrease in TEG R-time was observed at 30 minutes post-reversal. R-time increased at 12- and 24-hours to baseline levels. Significant changes were not observed in K-time, clot strength, maximum amplitude, or coagulation index.

Conclusions

TEG R-time may be able to detect a change in anticoagulation activity of DOACs in ICH after anticoagulation reversal. R-time decreases acutely after anticoagulation reversal and rebounds at 12- and 24-hours post-reversal.

Performance of direct oral anticoagulant (DOAC) testing by hemostasis laboratories: The Australasian/Asia-Pacific experience

INTRODUCTION

Direct oral anticoagulants (DOACs) reflect anticoagulation agents given to treat or prevent thrombosis, having largely replaced vitamin K antagonists (VKAs) such as warfarin. DOACs are given in fixed daily doses and generally do not need monitoring. However, there may be a variety of reasons that justify measurement of plasma DOAC levels in individual patients.

METHODS

We report updated findings for DOAC testing in our geographic region, using recent data from the RCPAQAP, an international external quality assessment (EQA) program, currently with some 40-60 participants in each of the different DOAC (rivaroxaban, apixaban, dabigatran) modules, to assess laboratory performance in this area. Data has been assessed for the past 5 years (2019-2023 inclusive), with 20 samples each per DOAC.

RESULTS

Data shows a limited repertoire of assays in use, and mostly consistency in reported numerical values when assessing proficiency samples. Available assays mostly comprised reagents from four manufacturing suppliers. There was good consistency across what participants identified as 'DOAC detected', but some variability when participants attempted to grade DOAC levels as low vs moderate vs high. Inter-laboratory/method coefficient of variation (CVs) were generally <15% for each DOAC, when present at >100 ng/mL.

CONCLUSION

We hope our findings, reflecting on mostly consistent reporting of DOAC levels and interpretation provides reassurance for clinicians requesting these measurements, and helps support their implementation in regions where there is a paucity of test availability.

Co-administration of Four-Factor Prothrombin Complex Concentrate With Andexanet alfa for Reversal of Nontraumatic Intracranial Hemorrhage

Objective: Andexanet alfa is approved for the reversal of life-threatening or uncontrolled bleeding due to factor-Xa inhibitors. Data are limited on outcomes for patients who receive both andexanet alfa and 4-factor prothrombin complex concentrate (4F-PCC). The aim of this case series is to evaluate the safety and efficacy outcomes in patients receiving the two agents in combination. Methods: Electronic medical records of patients who received both 4F-PCC and andexanet alfa for nontraumatic intracranial hemorrhage from January 2019 to March 2022 were retrospectively reviewed. Hemostatic efficacy and complications related to concurrent use of 4F-PCC with andexanet alfa were documented. Results: Nine patients received 4F-PCC and andexanet alfa for reversal of factor Xa inhibitor-associated intracranial bleeding, eight of whom required reversal of apixaban. Of these nine patients, five patients died within 28 days for a 56% incidence of mortality. The average time from 4F-PCC administration to andexanet alfa administration was 3 hours and 9 minutes. Most doses of andexanet alfa were given for concern for bleed expansion after 4F-PCC administration. Hemostatic efficacy based on stability of repeat computed tomography scans post-administration of both agents was found in six patients (66.67%), with a 55.56% n incidence of thromboembolism, including two pulmonary embolisms, two deep vein thromboses, and one renal artery thrombosis. Conclusion: Risks and benefits should be weighed to determine if there is benefit to adding andexanet alfa to 4F-PCC in patients with incomplete hemostasis and life-threatening hemorrhage. The combination of andexanet alfa and 4F-PCC may increase the risk of thrombotic complications without improving mortality.

Design and rationale for REVERXaL: A real-world study of patients with factor Xa inhibitor-associated major bleeds

BACKGROUND

The prevalence of anticoagulation treatment is increasing as an aging global population faces a high burden of cardiovascular comorbidities. Direct oral anticoagulants, including factor Xa inhibitors (FXai), are replacing vitamin K antagonists as the most commonly prescribed treatment for reducing risk of thrombotic events. While the risk of FXai-associated spontaneous bleeds is established, less is understood about their management and the effect of treatment on clinical and patient-reported outcomes. The primary objectives of the REVERXaL study are to describe patient characteristics, health care interventions during the acute-care phase, in-hospital outcomes, and associations between timing of reversal/replacement agent administration and in-hospital outcomes. Secondary/exploratory objectives focus on clinical assessments and patient-reported outcome measures (PROMs) at 30 and 90 days.

METHODS

REVERXaL is a multinational, observational study of hospitalized patients with FXai-associated major bleeds in Germany, Japan, the United Kingdom, and the United States. The study includes 2 cohorts of approximately 2000 patients each. Cohort A is a historic cohort for whom medical chart data will be collected from hospitalization to discharge for patients admitted for major bleeds during FXai use within 2 years prior to enrollment of Cohort B. Cohort B will prospectively enroll patients administered any reversal/replacement agent during hospitalization to manage FXai-associated major bleeds and will include the collection of clinical outcomes and PROMs data over 3 months.

CONCLUSIONS

REVERXaL will generate insights on patient characteristics, treatment approaches, and associated outcomes in patients hospitalized with FXai-associated major bleeds. These data may inform clinical practice and streamline treatment pathways in this population.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; unique identifier: NCT06147830.

Optimizing antithrombotic therapy in patients with coexisting cardiovascular and gastrointestinal disease

Balancing the safety and efficacy of antithrombotic agents in patients with gastrointestinal disorders is challenging because of the potential for interference with the absorption of antithrombotic drugs and for an increased risk of bleeding. In this Review, we address considerations for enteral antithrombotic therapy in patients with cardiovascular disease and gastrointestinal comorbidities. For those with gastrointestinal bleeding (GIB), we summarize a general scheme for risk stratification and clinical evidence on risk reduction approaches, such as limiting the use of concomitant medications that increase the risk of GIB and the potential utility of gastrointestinal protection strategies (such as proton pump inhibitors or histamine type 2 receptor antagonists). Furthermore, we summarize the best available evidence and potential gaps in our knowledge on tailoring antithrombotic therapy in patients with active or recent GIB and in those at high risk of GIB but without active or recent GIB. Finally, we review the recommendations provided by major medical societies, highlighting the crucial role of teamwork and multidisciplinary discussions to customize the antithrombotic regimen in patients with coexisting cardiovascular and gastrointestinal diseases.

Long-Term Safety of a Four-Factor Prothrombin Complex Concentrate (Kcentra®/Beriplex® P/N): An Updated Pharmacovigilance Review

INTRODUCTION

 Four-factor prothrombin complex concentrate (4F-PCC) is recommended for vitamin K antagonist reversal in patients with major bleeding or in need of surgery. The most important risk associated with the use of 4F-PCC is the occurrence of thromboembolic events (TEEs). In this review, we aim to evaluate the safety profile of a 4F-PCC (Kcentra®/Beriplex® P/N; CSL Behring, Marburg, Germany) by reviewing pharmacovigilance data.

METHODS

 A retrospective analysis of postmarketing pharmacovigilance data of Kcentra®/Beriplex® P/N from February 1996 to April 2022 was performed and complemented by a review of clinical studies published between January 2012 and April 2022.

RESULTS

 A total of 2,321,443 standard infusions of Kcentra®/Beriplex® P/N were administered during the evaluation period. Adverse drug reactions (ADRs) were reported in 614 cases (∼1 per 3,781 standard infusions) and 233 of these cases (37.9%) experienced suspected TEEs related to 4F-PCC (∼1 per 9,963 standard infusions); most of these cases had pre-existing or concomitant conditions likely to be significant risk factors for thrombosis. TEE rates were similar when 4F-PCC was used on-label or off-label for direct oral anticoagulant-associated bleeding. Thirty-six cases (5.9%) reported hypersensitivity type reactions (∼1 per 64,485 standard infusions). No confirmed case of viral transmission related to 4F-PCC use was reported. The published literature also revealed a favorable safety profile of 4F-PCC.

CONCLUSION

 Analysis of postmarketing pharmacovigilance safety reports demonstrated that treatment with 4F-PCC was associated with few ADRs and a low rate of TEEs across multiple indications and settings, thus confirming a positive safety profile of 4F-PCC.

Development of a Medication-Use Evaluation Template for Andexanet Alfa in the Reversal of Anticoagulation With Factor Xa Inhibitors

Medication-use evaluations are meant to ensure that medication-use processes are consistent with prevailing standards of care, assure optimal use of therapy, and reduce the risk of medication-related problems. Reversal agents for direct oral anticoagulants are a worthy focus for medication-use evaluations for reasons of efficacy, safety, and cost. A multidisciplinary team of experts developed 2 medication-use evaluation templates illustrating the application of professional society guidelines to the appropriate use of andexanet alfa.

Strategies to prevent blood loss and reduce transfusion in emergency general surgery, WSES-AAST consensus paper

Emergency general surgeons often provide care to severely ill patients requiring surgical interventions and intensive support. One of the primary drivers of morbidity and mortality is perioperative bleeding. In general, when addressing life threatening haemorrhage, blood transfusion can become an essential part of overall resuscitation. However, under all circumstances, indications for blood transfusion must be accurately evaluated. When patients decline blood transfusions, regardless of the reason, surgeons should aim to provide optimal care and respect and accommodate each patient's values and target the best outcome possible given the patient's desires and his/her clinical condition. The aim of this position paper was to perform a review of the existing literature and to provide comprehensive recommendations on organizational, surgical, anaesthetic, and haemostatic strategies that can be used to provide optimal peri-operative blood management, reduce, or avoid blood transfusions and ultimately improve patient outcomes.

Thrombotic and Hemorrhagic Outcomes After Elective Surgery in Preoperatively Anticoagulated Patients

OBJECTIVE

To better understand the incidence and timing of thrombotic and hemorrhagic complications in anticoagulated patients undergoing elective surgery.

METHODS

Using institutional American College of Surgeons National Surgical Quality Improvement Program data, we identified patients receiving preoperative anticoagulation undergoing elective surgery between 2011 and 2021. Medical records review supplemented National Surgical Quality Improvement Program data to detail complication and anticoagulation type and timing. Outcomes for postoperative hemorrhage, acute venous thromboembolism (VTE), and cerebrovascular accident (CVA) were collected.

RESULTS

A total of 1442 patients met inclusion criteria, and 84 patients (5.8%) experienced 1 or more complications. There were 4 CVA (0.3%), 16 VTE (1.1%), and 68 bleeding (4.7%) events postoperatively. Three patients (75%) with CVA, 10 patients (62.5%) with VTE, and 18 patients (26.5%) with postoperative bleeding had resumed therapeutic anticoagulation before the complication. In terms of long-term sequelae in the CVA cohort, there was 1 mortality (25%), and an additional patient (25%) continues to experience long-term physical and mild cognitive impairments. Patients who experienced postoperative VTE required only anticoagulation adjustments. In patients who experienced bleeding complications, 6 (8.8%) required intensive care unit admissions, and there was 1 mortality (1.5%).

CONCLUSION

Despite the increased use of anticoagulation over time, balancing postoperative bleeding and thrombotic risks remains challenging. Bleeding complications were most common in preoperatively anticoagulated patients undergoing elective surgery. Earlier postoperative resumption of anticoagulation is unlikely to prevent thrombotic events as 65% of patients had already resumed therapeutic anticoagulation.

Effects of dabigatran, rivaroxaban, and apixaban on fibrin network permeability, thrombin generation, and fibrinolysis

INTRODUCTION

There are important pharmacological differences between direct oral anticoagulants (DOAC) and a deeper knowledge of how they influence different aspects of hemostasis in patients on treatment is desirable.

MATERIALS AND METHODS

Blood samples from patients on dabigatran (n = 23), rivaroxaban (n = 26), or apixaban (n = 20) were analyzed with a fibrin network permeability assay, a turbidimetric clotting and lysis assay, the calibrated automated thrombogram (CAT), plasma levels of thrombin-antithrombin complex (TAT) and D-dimer, as well as DOAC concentrations, PT-INR and aPTT. As a comparison, we also analyzed samples from 27 patients on treatment with warfarin.

RESULTS

Patients on dabigatran had a more permeable fibrin network, longer lag time (CAT and turbidimetric assay), and lower levels of D-dimer in plasma, compared with patients on rivaroxaban- and apixaban treatment, and a more permeable fibrin network than patients on warfarin. Clot lysis time was slightly longer in patients on dabigatran than in patients on rivaroxaban. Warfarin patients formed a more permeable fibrin network than patients on apixaban, had longer lag time than patients on rivaroxaban (CAT assay), and lower peak thrombin and ETP compared to patients on treatment with both FXa-inhibitors.

CONCLUSIONS

Results from this study indicate dabigatran treatment is a more potent anticoagulant than apixaban and rivaroxaban. However, as these results are not supported by clinical data, they are probably more related to the assays used and highlight the difficulty of measuring and comparing the effect of anticoagulants.

Reprint of: Four-factor prothrombin complex concentrate versus andexanet alfa for direct oral anticoagulant reversal

BACKGROUND

Optimal reversal agent for direct oral anticoagulant (DOAC)-associated major bleeding has not been described. Before the approval of andexanet alfa (AA) in 2018, 4-factor prothrombin complex concentrate (4F-PCC) was recommended by major guidelines. Currently, AA is recommended as the first-line agent by most guidelines. With a paucity of literature comparing the 2 agents, there is clinical value in assessing hemostatic efficacy and safety of the 2 agents.

OBJECTIVE

This study aimed to evaluate hemostatic efficacy and safety of AA and 4F-PCC in all DOAC-associated major bleedings.

METHODS

A multicenter, retrospective chart review was performed of adult subjects who were admitted for a DOAC-associated major bleeding and received 4F-PCC from February 2018 to May 2019 or AA from May 2019 to September 2021. Some of the exclusion criteria included not receiving a DOAC, receiving multiple reversal agents during the same hospitalization, receiving reversal for any nonmajor bleeding indication, and not receiving the full dose of a reversal agent. The primary outcome was hemostatic efficacy 24 hours after the end of the reversal agent administration. Secondary outcomes included time to administration, hospital mortality, length of stay, need for surgery, and need for additional blood product. Safety outcome was incidence of thrombotic events.

RESULTS

There were 99 subjects included in the 4F-PCC group and 84 subjects in the AA group. Hemostatic efficacy was achieved in 69 subjects (69.7%) in the 4F-PCC group and 63 subjects (75%) in the AA group (P = 0.927). In-hospital mortality was seen in 20 subjects (20.2%) in the 4F-PCC group and 10 subjects (11.9%) in the AA group. Thrombotic events were seen in 7 subjects (7.1%) in the 4F-PCC group and 6 subjects (7.1%) in the AA group.

CONCLUSIONS

There were no significant differences in hemostatic efficacy, in-hospital mortality, and number of thrombotic events between 4F-PCC and AA.

Anticoagulation reversal (vitamin K, prothrombin complex concentrates, idarucizumab, andexanet-α, protamine)

Bleeding events are common in patients prescribed anticoagulants and can have devastating consequences. Several specific and nonspecific agents have been developed to reverse the effects of anticoagulant drugs or toxins. Vitamin K, as the oldest of these antidotes, specifically counteracts the effects of pharmaceuticals and rodenticides designed to deplete stores of vitamin K-dependent factors. In cases of life-threatening bleeding, the addition of prothrombin complex concentrates (PCCs) allows for the immediate replacement of coagulation factors. While the use of PCCs has been extended to the non-specific reversal of the effects of newer direct oral anticoagulants, the specific agents idarucizumab, targeting dabigatran and andexanet-α, binding factor Xa inhibitors, have recently been developed and are being preferentially recommended by most guidelines. However, despite having rapid effects on correcting coagulopathy, there is to date a lack of robust evidence establishing the clear superiority of direct oral anticoagulant-specific reversal agents over PCCs in terms of haemostatic efficacy, safety or mortality. For andexanet-α, a potential signal of increased thromboembolic risks, comparatively high costs and low availability might also limit its use, even though emerging evidence appears to bolster its role in intracranial haemorrhage. Protamine is the specific agent for the reversal of unfractionated heparin anticoagulation used mainly in cardiovascular surgery. It is much less effective for low molecular weight heparin fragments and is usually reserved for cases with life-threatening bleeding.

Thromboembolic events after major bleeding events in patients with mechanical heart valves: a 13-year analysis

Anticoagulation in patients with mechanical heart valves (MHV) is associated with a risk of major bleeding episodes (MBE). In case of MBE, anticoagulant interruption is advocated. However, there is lack of data regarding the thrombo-embolic events (TE) risk associated with anticoagulant interruption. The main objective of the study was to evaluate the rate and risk factors of 6-months of TEs in patients with MHV experiencing MBE. This observational study was conducted over a 13-year period. Adult patients with a MHV presenting with a MBE were included. The main study endpoint was 6-month TEs, defined by clinical TEs or an echocardiographic documented thrombosis, occurring during an ICU stay or within 6-months. Thromboembolic events were recorded at ICU discharge, and 6 months after discharge. Seventy-nine MBEs were analysed, the rate of TEs at 6-months was 19% CI [11-29%]. The only difference of presentation and management between 6-month TEs and free-TE patients was the time without effective anticoagulation (TWA). The Receiver Operator Characteristic curve identified the value of 122 h of TWA as a cut-off. The multivariate analysis identified early bleeding recurrences (OR 3.62, 95% CI [1.07-12.25], p = 0.039), and TWA longer than 122 h (OR 4.24, 95% CI [1.24-14.5], p = 0.021), as independent risk factors for 6-month TEs. A higher rate of TE was associated with anticoagulation interruption longer than 5 days and early bleeding recurrences. However, the management should still be personalized and discussed for each case given the heterogeneity of causes of MBE and possibilities of haemostatic procedures.

Hemostatic Efficacy and Safety of 4-Factor Prothrombin Complex Concentrate in Doac-Associated Intracranial Hemorrhage

Background: Factor Xa (FXa) inhibitor use has increased over the last decade and though associated rates of major bleeding are lower compared to warfarin, outcomes from intracranial hemorrhage (ICH) are still significant. Targeted FXa inhibitor reversal agent became available in 2018, however use of 4-factor prothrombin complex concentrate (4F-PCC) for FXa inhibitor-associated ICH continues at many institutions. Objective: Evaluate the safety and hemostatic efficacy of 4F-PCC for FXa inhibitor-associated ICH. Methods: Single-center, retrospective study of patients who received 4F-PCC for FXa inhibitor-associated ICH. The primary efficacy endpoint was hemostasis and thrombosis was the main safety endpoint. Secondary endpoints included in-hospital mortality and discharge disposition. Results: 76 patients on apixaban or rivaroxaban were included. Good or excellent hemostasis was achieved in 80.3% of patients. Five patients experienced a thrombotic event. Favorable discharge disposition and lower in-hospital mortality was more likely in patients who achieved excellent hemostasis. Conclusion: 4F-PCC is safe and effective for FXa inhibitor associated ICH.

Four-factor Prothrombin Complex Concentrate During Liver Transplantation: A Retrospective Cohort Study

Background

Four-factor prothrombin complex concentrate (PCC) is a plasma product that contains factors II, VII, IX, X, protein C, and protein S. PCC can be used off-label to treat coagulopathy during orthotopic liver transplantation (OLT). However, its use comes with safety concerns regarding thrombosis. The purpose of our study is to determine the safety of PCC in OLT.

Methods

We conducted a retrospective cohort study of patients who received 4-factor PCC during OLT at our institution from January 1, 2018, to May 1, 2022, with a 1:1 match of 83 patients who received PCC and 83 patients who did not. We evaluated 30-d mortality, 1-y mortality, prevalence of thrombotic complications (portal vein thrombosis, deep venous thrombosis, myocardial infarction, and pulmonary embolus), and postoperative intensive care (ICU) length of stay (LOS).

Results

There was no significant difference in 30-d mortality (odds ratio [OR] 5; 95% confidence interval [CI], 0.58-42.8; P = 0.14), 1-y mortality (OR 3; 95% CI, 0.61-14.86; P = 0.18), or ICU LOS (OR -13.8; 95% CI, -39.2 to 11.6; P = 0.29). There was no increased incidence of thrombotic complications among patients receiving PCC 90 d after surgery, including portal vein thrombosis (OR 1.5; 95% CI, 0.42-5.32; P = 0.53), pulmonary embolus (OR 1; 95% CI, 0.14-7.1; P = 0.99), deep venous thrombosis (OR 0.67; 95% CI, 0.11-3.99; P = 0.66), and myocardial infarction (OR 1.67; 95% CI, 0.4-6.97; P = 0.48).

Conclusions

Although there was a statistically insignificant increase in mortality after PCC administration during OLT, we did not see a significant increase in perioperative complications, including thrombotic events and increased ICU LOS.

Massive Apixaban Overdose Confirmed with Blood Concentrations and Managed Without Bleeding: A Single Case Report

Background: Acute overdoses of apixaban, and other direct oral anticoagulants are relatively uncommon. The number of direct oral anticoagulants prescriptions in the United States is increasing, however reports on patient outcomes after documented overdose are sparse. Case report: A 76-year-old man with a past medical history of atrial fibrillation and taking apixaban 5 mg twice daily presented to the emergency department 10 hours after reportedly ingesting 60-70 of his pills. He was alert and had a normal physical examination. Blood tests demonstrated an INR of 12, platelets of 161 000 cells/mm3, hemoglobin 9.7 g/dL, and creatinine 1.81 mg/dL. He received 60 g of activated charcoal and 4 units of fresh frozen plasma prophylactically. Initial blood apixaban concentration was 4 000 ng/mL. Repeat blood apixaban concentrations were 3 000 ng/mL and 2 200 ng/mL at 7 and 14 hours, respectively (thrapeutic range 91-321 ng/mL for a 5 mg twice daily dose). The hybrid anti-factor Xa activity did not correlate with blood apixaban concentrations. Apixaban elimination followed first-order kinetics with an apparent elimination half-life of 14 hours in the presence of impaired renal function. He did not have any minor or major bleeding events.

Time to oral anticoagulant reversal in intracranial hemorrhage with an emergency medicine pharmacist presence

PURPOSE

Intracranial hemorrhage (ICH) is associated with high morbidity and mortality, with mortality rates up to 65%. Oral anticoagulants (OAC) are a major risk factor for ICH. Since these patients are usually diagnosed in the emergency department (ED), emergency medicine (EM) pharmacists can help ensure appropriate selection and delivery of medications in urgent situations including reversal agents for OAC-associated bleeding. The purpose of this study was to determine the impact EM pharmacist presence has on time to OAC reversal in patients presenting with an ICH.

PROCEDURES

This was a retrospective, single-center cohort study evaluating time to reversal of OAC-associated ICH at a level one trauma center between November 2016 and September 2022. Patients 18 years or older who presented to the ED with an OAC-associated ICH and received at least one dose of an emergent reversal agent were included. Patients were excluded if their ICH was diagnosed at an outside facility, if they received emergent reversal agents for other indications, or if they had do not resuscitate orders upon admission. The primary outcome was time to administration of reversal agent with or without an EM pharmacist present, represented as median [interquartile range]. Secondary outcomes included hematoma expansion, hospital length of stay, intensive care unit LOS, and in-hospital mortality.

RESULTS

Of the 157 patients evaluated, 83 met criteria for inclusion. Majority of patients presented with warfarin-associated ICH (55%) and the most common indication for OAC was atrial fibrillation (66%). The most common type of ICH was intracerebral hemorrhage (35%). The median time to emergent reversal agent administration was significantly shorter in the EM pharmacist group (50 min [31-65] vs. 85 min [51-121], p < 0.01). No significant differences in secondary outcomes existed.

CONCLUSIONS

The presence of an EM pharmacist at the bedside of patients who present to the ED with ICH was associated with a decrease in the time to OAC reversal by 36 min. Presence of an EM pharmacist was not associated with improved clinical outcomes for ICH in our study. Larger trials are warranted to determine whether the presence of an EM pharmacist is associated with improved functional and clinical outcomes in patients with OAC-associated ICH and whether time to newer reversal agents, other than 4F-PCC, has an effect on outcomes.

Evaluation of modified fixed dose four-factor prothrombin complex concentrate for warfarin reversal

Non-activated four-factor prothrombin complex concentrate (4 F-PCC) has emerged as the preferred reversal strategy for patients on warfarin with life-threatening bleeding. Current dosing recommendations for 4 F-PCC require pre-treatment international normalized ratio (INR) and bodyweight values, resulting in ordering and administration delays. Studies have shown that alternative dosing regimens are safe and efficacious. This retrospective, single-center, pre- and post-protocol analysis was conducted to assess the efficacy of a pharmacist driven modified fixed-dose 4 F-PCC regimen versus package insert weight- and INR-based dosing regimen for warfarin reversal. The primary outcome was achievement of INR less than two. Secondary outcomes included dose and cost of 4 F-PCC, a time analysis, incidence of concomitant vitamin K administration, and incidence of thrombosis within seven days of 4 F-PCC. There were 195 patients included in the analysis, with 74 in the pre-cohort and 121 in the post-cohort. Baseline characteristics were similar between cohorts with the most common indication for warfarin use being atrial fibrillation (48.6% versus 47.1%) and reversal being intracerebral hemorrhage (68.9% versus 43.0%). Achievement of the primary endpoint occurred in 92% versus 95% (p = 0.097) of patients. A statistically significant difference was seen between cohorts regarding median dose and cost of 4 F-PCC administered (p < 0.001). Eleven thromboembolic events occurred with three events in the pre-cohort and eight events in the post-cohort (p = 0.453). A fixed-dose of 1500IU of 4 F-PCC was effective in reversing INR to less than two in most patients regardless of reversal indication with minimal thrombotic risks.

Evaluation and treatment of gastrointestinal bleeding in patients taking anticoagulants presenting to the emergency department

This manuscript is a consensus document of an expert panel on the Evaluation and Treatment of Gastrointestinal Bleeding in Patients Taking Anticoagulants Presenting to the Emergency Department, sponsored by the American College of Emergency Physicians.

Effect of low- versus high-dose 4-factor prothrombin complex concentrate in factor Xa inhibitor-associated bleeding: A qualitative systematic review

PURPOSE

The purpose of this review is to evaluate current literature on the treatment of factor Xa inhibitor-associated bleeds with 4-factor prothrombin complex concentrate (4F-PCC), with a focus on the effect of low versus high dosing of 4F-PCC on hemostatic efficacy and safety outcomes.

SUMMARY

A search of PubMed and EBSCOhost was performed to identify studies evaluating patients with a factor Xa inhibitor-bleed treated with 4F-PCC at either low or high doses. Studies of patients receiving alternative reversal agents such as fresh frozen plasma and andexanet alfa or where no comparator group was evaluated were excluded from the analysis. To assess the effect of these 4F-PCC dosing strategies, the primary outcome of interest was hemostatic efficacy. Four studies meeting inclusion criteria were included in this review. In each of the included studies, similar rates of hemostatic efficacy, hospital mortality, and venous thromboembolism were observed in the low- and high-dose cohorts.

CONCLUSION

These results suggest low- and high-dose 4F-PCC may confer similar clinical effectiveness and safety; however, these findings should be evaluated and confirmed with future prospective studies.

The risk of hemorrhagic complications after anticoagulation therapy in trauma patients: A multicenter evaluation

BACKGROUND

The use of anticoagulation therapy (ACT) in trauma patients during the postinjury period presents a challenge given the increased risk of hemorrhage. Guidelines regarding whether and when to initiate ACT are lacking, and as a result, practice patterns vary widely. The purpose of this study is to describe the incidence of hemorrhagic complications in patients who received ACT during their hospitalization, identify risk factors, and characterize the required interventions.

METHODS

In this retrospective cohort study, all trauma admissions at two Level I trauma centers between January 2015 and December 2020 were reviewed. Patients with preexisting ACT use or those who developed a new indication for ACT were included for analysis. Demographic and outcome data were collected for those who received ACT during their admission. Comparisons were then made between the complications and no complications groups. A subgroup analysis was performed for all patients started on ACT within 14 days of injury.

RESULTS

A total of 812 patients were identified as having an indication for ACT, and 442 patients received ACT during the postinjury period. The overall incidence of hemorrhagic complications was 12.7%. Of those who sustained hemorrhagic complications, 18 required procedural intervention. On regression analysis, male sex, severe injuries, and the need for hemorrhage control surgery on arrival were all found to be associated with hemorrhagic complications after the initiation of ACT. Waiting 7 days to 14 days from the time of injury to initiate ACT reduced the odds of complications by 46% and 71%, respectively.

CONCLUSION

The use of ACT in trauma during the postinjury period is not without risk. Waiting 7 days to 14 days postinjury might greatly reduce the risk of hemorrhagic complications.

LEVEL OF EVIDENCE

Therapeutic/Care Management Study; Level IV.

Andexanet alfa versus PCC products for factor Xa inhibitor bleeding: A systematic review with meta-analysis

Previous meta-analyses assessed andexanet alfa (AA) or prothrombin complex concentrate (PCC) products for the treatment of Factor Xa inhibitor (FXaI)-associated major bleeding. However, they did not include recent studies or assess the impact of the risk of bias. We conducted a systematic review with meta-analysis on the effectiveness of AA versus PCC products for FXaI-associated major bleeding, inclusive of the studies' risk of bias. PubMed and Embase were searched for comparative studies assessing major bleeding in patients using FXaI who received AA or PCC. We used the Methodological Index for NOn-Randomized Studies (MINORS) checklist and one question from the Joanna Briggs Institute (JBI) Critical Appraisal of Case Series tool to assess the risk of bias. Random-effects meta-analyses were performed to provide a pooled estimate for the effect of AA versus PCC products on hemostatic efficacy, in-hospital mortality, 30-day mortality, and thrombotic events. Low-moderate risk of bias studies were meta-analyzed separately, as well as combined with high risk of bias studies. Eighteen comparative evaluations of AA versus PCC were identified. Twenty-eight percent of the studies (n = 5) had low-moderate risk and 72% (n = 13) had a high risk of bias. Studies with low-moderate risk of bias suggested improvements in hemostatic efficacy [Odds Ratio (OR) 2.72 (95% Confidence Interval (CI): 1.15-6.44); one study], lower in-hospital mortality [OR 0.48 (95% CI: 0.38-0.61); three studies], and reduced 30-day mortality [OR 0.49 (95% CI: 0.30-0.80); two studies] when AA was used versus PCC products. When studies were included regardless of the risk of bias, pooled effects showed improvements in hemostatic efficacy [OR 1.36 (95% CI: 1.01-1.84); 12 studies] and reductions in 30-day mortality [OR 0.53 (95% CI: 0.37-0.76); six studies] for AA versus PCC. The difference in thrombotic events with AA versus PCC was not statistically significant in the low-moderate, high, or combined risk of bias groups. The evidence from low-moderate quality real-world studies suggests that AA is superior to PCC in enhancing hemostatic efficacy and reducing in-hospital and 30-day mortality. When studies are assessed regardless of the risk of bias, the pooled hemostatic efficacy and 30-day mortality risk remain significantly better with AA versus PCC.

Clinical guideline on reversal of direct oral anticoagulants in patients with life threatening bleeding

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.

Perioperative care in infective endocarditis

Patients undergoing surgery for acute infective endocarditis are among those with the highest risk. Their preoperative condition has significant impact on outcomes. There are specific issues related with the preoperative situation, intraoperative findings, and postoperative management. In this narrative review, focus is placed on the most critical aspects in the perioperative period including the management and weaning from mechanical ventilation, the management of vasoplegia, the management of the chest open, antithrombotic therapy, transfusion, coagulopathy, management of atrial fibrillation, the duration of antibiotic therapy, and pacemaker implantation.

Fixed- Versus Variable-Dose Prothrombin Complex Concentrate for the Emergent Reversal of Vitamin K Antagonists: A Systematic Review and Meta-Analysis

OBJECTIVES

Four-factor prothrombin complex concentrate (4-PCC) is recommended for rapid reversal of vitamin K antagonists (VKAs) such as warfarin, yet optimal dosing remains uncertain.

DATA SOURCES

A systematic review was conducted of PubMed, Embase, and Ovid MEDLINE (Wolters Kluwer) databases from January 2000 to August 2023 for clinical studies comparing fixed- vs. variable-dose 4-PCC for emergent VKA reversal with at least one reported clinical outcome.

STUDY SELECTION

Abstracts and full texts were assessed independently and in duplicate by two reviewers.

DATA EXTRACTION

Data were extracted independently and in duplicate by two reviewers using predefined extraction forms.

DATA SYNTHESIS

The analysis comprised three randomized trials and 16 cohort studies comprising a total of 323 participants in randomized trials (161 in fixed dosage and 162 in variable dosage) and 1912 patients in cohort studies (858 in fixed-dose and 1054 in variable dose). Extracranial bleeding was the predominant indication, while intracranial hemorrhage varied. Overall, a fixed-dose regimen may be associated with a lower dose of 4-PCC and results in a reduction in 4-PCC administration time compared with a variable-dose regimen. A fixed-dose regimen also likely results in increased clinical hemostasis. While there is no clear difference between the two regimens in terms of achieving a goal international normalized ratio (INR) less than 2, a fixed-dose regimen is less likely to achieve a goal INR less than 1.5. High certainty evidence indicates that the fixed-dose regimen reduces both mortality and the occurrence of thromboembolic events. Additional subgroup analyses provides exploratory data to guide future studies.

CONCLUSIONS

A fixed-dose regimen for 4-PCC administration provides benefits over a variable-dose regimen in terms of dose reduction, faster administration time, improved clinical hemostasis, and reduced mortality and thromboembolic events. Further studies are warranted to better refine the optimal fixed-dose regimen.

Clinical Care Pathway and Management of Major Bleeding Associated with Nonvitamin K Antagonist Oral Anticoagulants: A Modified Delphi Consensus from Saudi Arabia and UAE

Background

The nonvitamin K antagonist oral anticoagulants (NOACs) have become the mainstay anticoagulation therapy for patients requiring oral anticoagulants (OACs) in the Gulf Council Cooperation (GCC) countries. The frequency of NOAC-associated major bleeding is expected to increase in the Emergency Department (ED). Nonetheless, we still lack local guidelines and recommendations for bleeding management in the region. The present Delphi-based consensus aims to establish a standardized and evidence-based clinical care pathway for managing NOAC-associated major bleeding in the Kingdom of Saudi Arabia (KSA) and the United Arab Emirates (UAE).

Methods

We adopted a three-step modified Delphi method to develop evidence-based recommendations through two voting rounds and an advisory meeting between the two rounds. A panel of 11 experts from the KSA and UAE participated in the consensus development.

Results

Twenty-eight statements reached the consensus level. These statements addressed key aspects of managing major bleeding events associated with NOACs, including the increased use of NOAC in clinical practice, clinical care pathways, and treatment options.

Conclusion

The present Delphi consensus provides evidence-based recommendations and protocols for the management of NOAC-associated bleeding in the region. Patients with major DOAC-induced bleeding should be referred to a well-equipped ED with standardized management protocols. A multidisciplinary approach is recommended for establishing the association between NOAC use and major bleeding. Treating physicians should have prompt access to specific reversal agents to optimize patient outcomes. Real-world evidence and national guidelines are needed to aid all stakeholders involved in NOAC-induced bleeding management.

Reversal and resumption of anticoagulants in patients with anticoagulant-associated intracerebral hemorrhage

The use of anticoagulants has become more frequent due to the progressive aging population and increased thromboembolic events. Consequently, the proportion of anticoagulant-associated intracerebral hemorrhage (AAICH) in stroke patients is gradually increasing. Compared with intracerebral hemorrhage (ICH) patients without coagulopathy, patients with AAICH may have larger hematomas, worse prognoses, and higher mortality. Given the need for anticoagulant reversal and resumption, the management of AAICH differs from that of conventional medical or surgical treatments for ICH, and it is more specific. Understanding the pharmacology of anticoagulants and identifying agents that can reverse their effects in the early stages are crucial for treating life-threatening AAICH. When patients transition beyond the acute phase and their vital signs stabilize, it is important to consider resuming anticoagulants at the right time to prevent the occurrence of further thromboembolism. However, the timing and strategy for reversing and resuming anticoagulants are still in a dilemma. Herein, we summarize the important clinical studies, reviews, and related guidelines published in the past few years that focus on the reversal and resumption of anticoagulants in AAICH patients to help implement decisive diagnosis and treatment strategies in the clinical setting.

Coagulation Tests and Reversal Agents in Patients Treated with Oral Anticoagulants: The Challenging Scenarios of Life-Threatening Bleeding and Unplanned Invasive Procedures

In clinical practice, the number of patients treated with direct oral anticoagulants (DOACs) has consistently increased over the years. Since anticoagulant therapy has been associated with an annual incidence of major bleeding (MB) events of approximately 2% to 3.5%, it is of paramount importance to understand how to manage anticoagulated patients with major or life-threatening bleeding. A considerable number of these patients' conditions necessitate hospitalization, and the administration of reversal agents may be imperative to manage and control bleeding episodes effectively. Importantly, effective strategies for reversing the anticoagulant effects of DOACs have been well recognized. Specifically, idarucizumab has obtained regulatory approval for the reversal of dabigatran, and andexanet alfa has recently been approved for reversing the effects of apixaban or rivaroxaban in patients experiencing life-threatening or uncontrolled bleeding events. Moreover, continuous endeavors are being made to develop supplementary reversal agents. In emergency scenarios where specific reversal agents might not be accessible, non-specific hemostatic agents such as prothrombin complex concentrate can be utilized to neutralize the anticoagulant effects of DOACs. However, it is paramount to emphasize that specific reversal agents, characterized by their efficacy and safety, should be the preferred choice when suitable. Moreover, it is worth noting that adherence to the guidelines for the reversal agents is poor, and there is a notable gap between international recommendations and actual clinical practices in this regard. This narrative review aims to provide physicians with a practical approach to managing specific reversal agents.

ANMCO/SIMEU consensus document on the use of reversal agents for antithrombotic therapies in patients with ongoing bleeding or at high risk of haemorrhagic events

In recent decades, an incredible evolution in antithrombotic therapies used for treating patients with atherosclerosis, atrial fibrillation, and venous thromboembolism has been observed, leading to the availability of increasingly safe drugs. Nonetheless, bleeding complications remain a significant concern, with considerable health, social, and economic implications. To improve the acute management of patients experiencing or at risk for major bleeding events, specific reversal agents for antithrombotic drugs have been recently developed. While these agents demonstrate effectiveness in small-scale pharmacodynamic studies and clinical trials, it is imperative to balance the benefits of reversing antiplatelet or anticoagulant therapy against the risk of prothrombotic effects. These risks include the potential loss of antithrombotic protection and the prothrombotic tendencies associated with bleeding, major surgery, or trauma. This joint document of the Italian Association of Hospital Cardiologists (Associazione Nazionale Medici Cardiologi Ospedalieri) and the Italian Society of Emergency Medicine (Società Italiana di Medicina d'Emergenza-Urgenza) delineates the key features and efficacy of available reversal agents. It also provides practical flowcharts to guide their use in patients with active bleeding or those at elevated risk of major bleeding events.

The use of andexanet alfa vs. 4-factor prothrombin complex concentrates in the setting of life-threatening intracranial hemorrhage

OBJECTIVE

Andexanet alfa is a targeted reversal agent for life threatening hemorrhage associated with direct acting oral anticoagulants (DOACs), but there is uncertainty regarding the benefit when compared to 4-factor prothrombin complex concentrate (4F-PCC) for this indication. We investigated the clinical outcomes and cost associated with reversal of DOACs in the setting of life-threatening intracranial hemorrhage (ICH).

METHODS

A retrospective evaluation was conducted to evaluate patients with ICH in the setting of anticoagulation with DOAC from 9/1/2013 to 4/30/2020. Patients were included in the study if they received reversal with either andexanet alfa or 4F-PCC.

RESULTS

Eighty-nine patients were included in the study. There was no statistically significant difference in 30-day mortality between patients who received andexanet alfa or 4F-PCC (52% vs. 35%, P  = 0.14). Radiographic stability of bleed was identified in 57% of patients receiving andexanet alfa vs. 58% of patients receiving 4F-PCC ( P  = 0.93). Median length of stay was not different between the andexanet alfa and 4F-PCC populations (7 days [IQR 6 - 12] vs. 6 days [IQR 3-12], P  = 0.66). Median cost of reversal agent was higher in patients receiving andexanet alfa compared to 4F-PCC ($15 000 [IQR 15 000-$27 000] vs. $11 650 [IQR $8567-$14 149]).

CONCLUSION

Among patients with life-threatening intracranial hemorrhage in the setting of DOAC therapy, no clinical differences were observed with respect to selection of reversal agent. Prothrombin complex concentrates remain a viable alternative to reversal of DOAC therapy though multicenter, randomized, prospective studies are needed to further evaluate the role of 4F-PCC in the reversal of DOAC therapy.

Clinical Pathways and Outcomes of Andexanet Alfa Administration for the Reversal of Critical Bleeding in Patients on Oral Direct Factor Xa Inhibitors

Background  Andexanet is U.S. Food and Drug Administration (FDA) approved for the reversal of critical bleeding from factor Xa inhibitors and off-label for surgical reversal. Data are lacking on andexanet administration processes. Methods  We retrospectively studied patients at a 23-hospital system who received andexanet from November 2019 to March 2023. Abstractors coded demographics, comorbidities, anticoagulant use, andexanet indication, and process times. The primary outcome was presentation-to-andexanet time; diagnosis, ordering, and administration times were calculated. Secondary outcomes included in-hospital postandexanet major thromboembolism/bleeding and mortality. Results  In total, 141 patients were analyzed. Andexanet indications were predominantly neurologic bleeding (85.8%). Twenty-four patients (17.0%) were transferred from nontertiary/academic centers to tertiary/academic centers. The median presentation-to-administration time was 192.5 minutes (interquartile range [IQR]: 108.0-337.0 minutes). Components were as follows: 72.5 minutes (IQR: 39.0-137.5 minutes) for bleeding diagnosis; 35.5 minutes (IQR: 0-96.5 minutes) for andexanet ordering; and 53.0 minutes (IQR: 38.5-78.5 minutes) for administration, which was longer at tertiary/academic hospitals (ratio 1.5, 95% confidence interval [CI]: 1.2-2.0, p  = 0.002). Gastrointestinal or other critical bleeding (ratio 2.59, 95% CI: 1.67-4.02, p  < 0.001), and tertiary/academic center treatment (ratio 1.58, 95% CI: 1.15-2.18, p  = 0.005), were associated with increased time. Major thromboembolism, bleeding, and mortality occurred in 10.6, 12.0, and 22.9% of patients, respectively. Conclusions  In our cohort, the median presentation-to-administration time was over 3 hours. Cumulative times were longer at tertiary/academic hospitals and for gastrointestinal/other bleeding. Postandexanet major thromboembolism/bleeding occurred more at tertiary/academic hospitals, possibly related to transfers. Prospective studies may elucidate clinical decision-making bottlenecks.

Safety and efficacy of fixed versus variable-dose prothrombin complex concentrate for emergent reversal of vitamin K antagonists: A systematic review and meta-analysis

STUDY OBJECTIVE

Four-factor prothrombin complex concentrate (4F-PCC) is standard of care for emergent vitamin K antagonist (VKA) reversal but optimal dosing is uncertain. This meta-analysis estimated the proportion of patients treated with fixed dose (FD) 4F-PCC who achieved adequate reversal and compared safety and efficacy of FD versus weight-based dose (WB) strategies.

METHODS

This review was conducted according to PRISMA guidelines. Medline and Scopus were searched and included studies evaluating FD regimens and comparing FD and WB for emergent VKA reversal. Data was pooled using random effects. Subgroup analyses examined heterogeneity. Risk of bias was assessed with Newcastle-Ottawa Scale and RoB2 score.

RESULTS

Twenty-three studies (n = 2055) were included with twelve (n = 1143) comparing FD versus WB. The proportion of patients achieving goal INR with FD varied depending on the INR target, being significantly higher for INR <2 (90.9%, 95% Confidence Interval (CI) 87.2, 94.06) compared to INR <1.6 (70.97%, 95%CI 65.33, 76.31). Compared to WB, FD was less likely to achieve a goal INR <1.6 (Risk Difference (RD) -13%, 95% CI -21, -4) but achieved similar reversal for a goal INR <2.0, (RD -1%, 95%CI -7, 4). There was no difference in hospital mortality (RD 4%, 95%CI -2, 9) or thrombosis (RD 0.0%, 95%CI -3, 3).

CONCLUSION

FD VKA reversal was associated with significantly lower attainment of goal INR compared to WB with lower INR targets. This did not translate to differences in hospital mortality, but these results should be interpreted cautiously in light of the observational nature of the included studies.

Is reversal of anticoagulants necessary in neurologically intact traumatic intracranial hemorrhage?

INTRODUCTION

Falls are the leading cause of injury in older individuals, with intracranial hemorrhage (ICH) being a common complication. Anticoagulants, such as vitamin K antagonist and direct oral anticoagulants, are increasingly utilized, and clinicians may question the necessity of reversal in patients with minor ICH, especially in the setting of increased risk of adverse events. This study aimed to identify a population of patients with minor traumatic ICH at low risk for poor-neurologic status where anticoagulant reversal may not improve outcomes.

METHODS

This retrospective cohort study utilized data accessed from 35 trauma centers from 2018 to 2021. Patients included had a preinjury anticoagulant regimen, ICH due to blunt trauma, Glasgow Coma Scale score of 15, an Abbreviated Injury Scale (AIS) head score from 2 to 4, and an AIS of ≤1 for non-head regions within 24 h of hospital arrival. Patients were excluded if they required an emergent neurosurgical procedure or were on a preinjury purinergic-P2 receptor-12 protein (P2Y12) inhibitor. The primary outcome was the rate of in-hospital mortality or hospice.

RESULTS

There were 654 patients on preinjury anticoagulation who were included with a minor traumatic ICH without neurologic deficits. Overall, 263 patients were reversed and 391 were not reversed. Twelve (4.6%) patients with in-hospital mortality or hospice were reversed compared with 19 (4.91%) patients who were not reversed (p = 0.861). A composite of hospital complications occurred in 21 (8%) reversed patients and 34 (8.7%) not reversed patients (p = 0.748). The average intensive care unit length of stay was 1.4 ± 3.4 days in the reversed group and 1.1 ± 1.8 days in the not reversed group (p = 0.069).

CONCLUSION

This study found no difference in hospital outcomes between patients with minor traumatic ICH on oral anticoagulants who were neurologically intact that were reversed versus those who were not reversed. Further studies should continue to define the subset of traumatic ICH patients who may not require reversal of anticoagulation.

Four-factor prothrombin complex concentrate versus andexanet alfa for direct oral anticoagulant reversal

BACKGROUND

Optimal reversal agent for direct oral anticoagulant (DOAC)-associated major bleeding has not been described. Before the approval of andexanet alfa (AA) in 2018, 4-factor prothrombin complex concentrate (4F-PCC) was recommended by major guidelines. Currently, AA is recommended as the first-line agent by most guidelines. With a paucity of literature comparing the 2 agents, there is clinical value in assessing hemostatic efficacy and safety of the 2 agents.

OBJECTIVE

This study aimed to evaluate hemostatic efficacy and safety of AA and 4F-PCC in all DOAC-associated major bleedings.

METHODS

A multicenter, retrospective chart review was performed of adult subjects who were admitted for a DOAC-associated major bleeding and received 4F-PCC from February 2018 to May 2019 or AA from May 2019 to September 2021. Some of the exclusion criteria included not receiving a DOAC, receiving multiple reversal agents during the same hospitalization, receiving reversal for any nonmajor bleeding indication, and not receiving the full dose of a reversal agent. The primary outcome was hemostatic efficacy 24 hours after the end of the reversal agent administration. Secondary outcomes included time to administration, hospital mortality, length of stay, need for surgery, and need for additional blood product. Safety outcome was incidence of thrombotic events.

RESULTS

There were 99 subjects included in the 4F-PCC group and 84 subjects in the AA group. Hemostatic efficacy was achieved in 69 subjects (69.7%) in the 4F-PCC group and 63 subjects (75%) in the AA group (P = 0.927). In-hospital mortality was seen in 20 subjects (20.2%) in the 4F-PCC group and 10 subjects (11.9%) in the AA group. Thrombotic events were seen in 7 subjects (7.1%) in the 4F-PCC group and 6 subjects (7.1%) in the AA group.

CONCLUSIONS

There were no significant differences in hemostatic efficacy, in-hospital mortality, and number of thrombotic events between 4F-PCC and AA.

Anesthesiology Resident Knowledge of Transfusion Medicine: Results From the Anesthesiology Transfusion Education Study

BACKGROUND

Transfusion of blood products is a common practice in anesthesiology. Inadequate transfusion medicine knowledge may lead to inappropriate transfusion practices and patient risk. Using a validated assessment tool modified for anesthesiology, we conducted a survey of anesthesiology residents in the United States to assess transfusion medicine knowledge.

METHODS

A validated transfusion medicine examination and accompanying survey were forwarded by program directors to residents for anonymous completion on May 5 and closed on June 30, 2021. The outcome of interest was the mean examination score. Secondary areas of interest were performance by year of training and previous educational experience in transfusion reported by the trainees. Rasch analysis was performed on the examination quality and individual question performance. Kruskal-Wallis H tests were used to identify differences between mean scores. Post hoc comparisons were used to assess specific pairwise differences between mean test scores by survey variable.

RESULTS

Four hundred twenty-three anesthesiology residents in 37 programs completed the examination. The mean score was 45.5% ± 12.6%. There was a significant difference in mean cumulative examination scores between different resident training levels ( P < 0.001). There was a significant difference in scores between clinical anesthesia (CA)-1 and CA-2 residents ( P = 0.011) and CA-1 and CA-3 residents ( P = 0.012). No significant difference in examination scores was observed between CA-2 and CA-3 residents ( P = 0.95). All these subgroups scored below 50% on the examination. Significant differences between the residency training programs and cumulative scores were identified ( P < 0.001).

CONCLUSIONS

This examination highlights gaps in transfusion medicine knowledge within US anesthesiology residents. Targeted education may improve knowledge in this area and patient care.

Four-factor prothrombin complex concentrate versus andexanet alfa for the reversal of traumatic brain injuries

BACKGROUND

Andexanet alfa was approved in 2018 for reversal of direct oral anticoagulants but due to issues of cost and access, four-factor prothrombin complex concentrate (4F-PCC) continues to be used for this indication. The objective of this study is to evaluate outcomes of reversal with these agents in patients with isolated traumatic brain injuries (TBI).

METHODS

This is a retrospective review of 35 trauma centres from 2014 to 2021. Patients were included with an Abbreviated Injury Scale (AIS)>2 for head and having received andexanet alfa or 4F-PCC within 24 hours of admission. Patients were excluded if P2Y12 inhibitor use or AIS>2 outside of head. Primary outcome includes rate of mortality/hospice at hospital discharge. Secondary outcomes include a composite of serious hospital complications. A subgroup analysis of severe TBI patients (AIS head 4 or 5) was completed. Multivariable logistic regression was used to account for differences in comorbidities and TBI severity.

RESULTS

4F-PCC was given to 265 patients with another 59 receiving andexanet alfa. Patients in the andexanet alfa group were more likely to have an AIS head score of 5 (47.5% vs 26.1%; p<0.005). After adjusting for severity of TBI and comorbidities with regard to tomortality/hospice, there were 15 (25.4%) patients in the andexanet alfa group and 49 (18.5%) in the 4F-PCC group (OR 1.34; 95% CI 0.67 to 2.71). This remained consistent when looking at severe patients with TBI with 12 (28.6%) andexanet alfa patients and 37 (28.7%) 4F-PCC patients (OR 0.93 (95% CI 0.40 to 2.16)). Severe hospital complications were also similar between groups with 5 (8.5%) andexanet alfa patients as compared with 21 (7.9%) 4F-PCC patients (OR 1.01; 95% CI 0.36 to 2.88).

CONCLUSION

There was no firm conclusion on the treatment effect in mortality/hospice or serious complications among isolated TBI patients reversed with 4F-PCC as compared with andexanet alfa.

Management of Antithrombotic Drugs in Patients with Isolated Traumatic Brain Injury: An Intersociety Consensus Document

BACKGROUND

All available recommendations about the management of antithrombotic therapies (ATs) in patients who experienced traumatic brain injury (TBI) are mainly based on expert opinion because of the lack of strength in the available evidence-based medicine. Currently, the withdrawal and the resumption of AT in these patients is empirical, widely variable, and based on the individual assessment of the attending physician. The main difficulty is to balance the thrombotic and hemorrhagic risks to improve patient outcome.

METHODS

Under the endorsement of the Neurotraumatology Section of Italian Society of Neurosurgery, the Italian Society for the Study about Haemostasis and Thrombosis, the Italian Society of Anaesthesia, Analgesia, Resuscitation, and Intensive Care, and the European Association of Neurosurgical Societies, a working group (WG) of clinicians completed two rounds of questionnaires, using the Delphi method, in a multidisciplinary setting. A table for thrombotic and bleeding risk, with a dichotomization in high risk and low risk, was established before questionnaire administration. In this table, the risk is calculated by matching different isolated TBI (iTBI) scenarios such as acute and chronic subdural hematomas, extradural hematoma, brain contusion (intracerebral hemorrhage), and traumatic subarachnoid hemorrhage with patients under active AT treatment. The registered indication could include AT primary prevention, cardiac valve prosthesis, vascular stents, venous thromboembolism, and atrial fibrillation.

RESULTS

The WG proposed a total of 28 statements encompassing the most common clinical scenarios about the withdrawal of antiplatelets, vitamin K antagonists, and direct oral anticoagulants in patients who experienced blunt iTBI. The WG voted on the grade of appropriateness of seven recommended interventions. Overall, the panel reached an agreement for 20 of 28 (71%) questions, deeming 11 of 28 (39%) as appropriate and 9 of 28 (32%) as inappropriate interventions. The appropriateness of intervention was rated as uncertain for 8 of 28 (28%) questions.

CONCLUSIONS

The initial establishment of a thrombotic and/or bleeding risk scoring system can provide a vital theoretical basis for the evaluation of effective management in individuals under AT who sustained an iTBI. The listed recommendations can be implemented into local protocols for a more homogeneous strategy. Validation using large cohorts of patients needs to be developed. This is the first part of a project to update the management of AT in patients with iTBI.

Characterization of an andexanet alfa administration protocol guided by drug-specific quantitative anti-Xa assays

Following FDA approval in 2018, consensus guidelines recommend andexanet alfa as first-line therapy for the management of life-threatening or uncontrollable bleeding in patients taking oral factor Xa (FXa) inhibitors. Dosing is based on the specific FXa inhibitor and dose, and the time elapsed since the patient's last administration of the medication. Additionally, at our institution, anti-FXa screens and drug-specific assays are obtained to guide subsequent dosing based on institution protocol. The objective of this study was to evaluate andexanet alfa utilization based on anti-Xa and FXa-inhibitor-specific assays and assess associated outcomes. This was a retrospective, single-center study aimed to describe the use of anti-FXa and specific direct oral anticoagulant assays to guide the utilization and administration of andexanet alfa. Secondary endpoints evaluated included thrombotic events during index hospitalization, hospital length of stay, hospital mortality, and discharge disposition. Overall, most patients were prescribed apixaban for atrial fibrillation and received andexanet alfa for reversal of intracranial hemorrhage in the emergency department. In general, DOAC-specific assays were concordant with last known times; however, there appears to be minimal correlation with DOAC-specific assay levels and survival. There were 9 thrombotic events (8.7%) in 8 patients. In this cohort, collection of an anti-FXa assay screen was a practical strategy to guide reversal with andexanet alfa; however, the addition of DOAC-specific assay levels may not enhance clinical utility.

Trends in Anticoagulant Utilization and Clinical Outcomes for Cancer-Associated Thrombosis: A Multicenter Cohort Study in Thailand's Upper-Middle-Income Country Setting

PURPOSE

To evaluate anticoagulant trends and clinical outcomes in the management of cancer-associated thrombosis (CAT) within Thailand, an upper-middle-income country (UMIC).

METHODS

This multicenter retrospective cohort study included adult patients with cancer diagnosed with venous thromboembolism (VTE) hospitalized in Thailand from 2017 to 2021. Anticoagulants were classified as low-molecular-weight heparin (LMWH), direct oral anticoagulants (DOACs), and warfarin. Prescription trends were assessed, and patients were followed for 1 year, or until 2022 to evaluate outcomes. The primary effectiveness outcome was recurrent VTE, whereas the primary safety outcome was major bleeding. Secondary outcomes included net clinical benefit and all-cause mortality. Treatment effects were examined using inverse probability of treatment weighting (IPTW) Cox proportional hazards models.

RESULTS

Among 1,611 patients (61.3% female; mean age, 58.8 years; standard deviation, 13.1 years), 86% received LMWH, 10% warfarin, and 4% DOACs. In the study cohort, LMWH prescriptions remained consistent, warfarin use declined, and DOAC prescriptions notably increased. In IPTW analysis, DOACs showed comparable rates of VTE recurrence (weighted hazard ratio [HR], 0.77 [95% CI, 0.22 to 2.70]; P = .679) and major bleeding (weighted HR, 0.62 [95% CI, 0.15 to 2.55]; P = .506) with LMWH. Warfarin had a higher risk of major bleeding (weighted HR, 2.74 [95% CI, 1.12 to 6.72]; P = .028) but a similar rate of VTE recurrence (weighted HR, 1.46 [95% CI, 0.75 to 2.84]; P = .271) compared with LMWH. Secondary outcomes were consistent across groups.

CONCLUSION

LMWH remains the primary treatment for CAT, in line with current guidelines. The study highlights the challenges faced in these settings with the continuous use of warfarin. The comparable efficacy and safety of DOACs with LMWH suggest a potential shift in CAT management within UMICs.