Idarucizumab for Dabigatran Reversal

Perioperative Management of Traditional and Direct Oral Anticoagulants in Hip Fracture Patients

Hip fractures are an increasingly common injury in the senior population and almost always require surgical fixation or prosthetic replacement. These surgeries, according to the American Academy of Orthopaedic Surgeons, are considered high-risk for bleeding, especially in a population fraught with comorbidities and often presenting on anticoagulation medications. Direct oral anticoagulants represent a class of drugs that have been becoming more popular in use in this population, with many benefits over the historically used Warfarin. There are recommendations for preoperative discontinuation and postoperative resumption of these medications, which can be more readily managed for elective surgeries. However, there is a paucity of literature detailing best practice guidelines for the perioperative management of direct oral anticoagulants when a patient presents with a hip fracture. This review article summary of the periprocedural management of DOACs for hip surgery was developed by examining the American College of Chest Physicians evidence-based clinical practice guidelines, Perioperative Guidelines on Antiplatelet and Anticoagulant Agents written by anesthesiologists, various retrospective studies, and drug labels for pharmacokinetic data. These recommendations should be used as a guideline, along with the collaboration of multidisciplinary hospital teams during inpatient admission, to manage these complex patients.

Is there a role for the laboratory monitoring in the management of specific antidotes of direct oral anticoagulants?

Given the growing number of patients receiving direct oral anticoagulant (DOAC), patients requiring rapid neutralization is also increasing in case of major bleedings or urgent surgery/procedures. Idarucizumab is commercialized as a specific antidote to dabigatran while andexanet alfa has gained the Food and Drug Administration and the European Medicines Agency approval as an oral anti-factor Xa inhibitors antidote. Other antidotes or hemostatic agents are still under preclinical or clinical development, the most advanced being ciraparantag. DOAC plasma levels measurement allows to appropriately select patient for antidote administration and may prevent unnecessary prescription of expensive molecules in some acute clinical settings. However, these tests might be inconclusive after some antidote administration, namely andexanet alfa and ciraparantag. The benefit of laboratory monitoring following DOAC reversal remains unclear. Here, we sought to provide an overview of the key studies evaluating the safety and efficacy of DOAC reversal using the most developed/commercialized specific antidotes, to discuss the potential role of the laboratory monitoring in the management of patients receiving DOAC specific antidotes and to highlight the areas that deserve further investigations in order to establish the exact role of laboratory monitoring in the appropriate management of DOAC specific antidotes.

Ultra-Early Hemostatic Therapy for Acute Intracerebral Hemorrhage: An Updated Review

Intracerebral hemorrhage (ICH) is the second most common type of stroke, accounting for approximately 10-20% of all strokes, and is linked to severe neurological disability and death. Since the most accurate predictor of outcome in patients with ICH is hematoma volume, there is a great need for pharmacologic therapy that can reduce hematoma expansion and resultant mass effect and edema. This is especially critical within the ultra-early window of 3-4 hours after the presentation. Hemostatic therapies are exceptionally important for those patients taking antiplatelet or anticoagulant medications to reverse the effects of these medications and therefore prevent hematoma expansion. Furthermore, the recent publication of the 2023 Guideline for the Management of Patients with Aneurysmal Subarachnoid Hemorrhage by the American Heart Association/American Stroke Association, the first update to the guidelines since 2012, underscores the importance of optimizing anticoagulation reversal for this population. The purpose of this selective, nonsystematic review is to examine current literature regarding the use of hemostatic therapies in ICH, with particular attention paid to antiplatelet, anticoagulation, and antifibrinolytic therapies.

Trends in Oral Anticoagulant Use and Individual Expenditures Across the United States from 2014 to 2020

BACKGROUND

Landmark clinical trials have expended the indications for the direct oral anticoagulants (DOACs), but contemporary data on usage and expenditure patterns are lacking.

OBJECTIVE

This study aimed to assess annual trends in oral anticoagulant (OAC) utilization and expenditure across the United States (US) from 2014 to 2020.

METHODS

We utilized the Medical Expenditure Panel Survey (MEPS) to study the trends of use and expenditures of warfarin, dabigatran, rivaroxaban, apixaban, and edoxaban between 2014 and 2020 in the US. Survey respondents reported OAC use within the past year, which was verified against pharmacy records. Payment information was obtained from the respondent's pharmacy and was categorized as third-party or self/out-of-pocket. Potential indications and medical conditions of interest for OAC therapy were identified from respondent-reported medical conditions. We estimated the national number of OAC users and total expenditures across age, sex, race, ethnicity, insurance, and medical condition subgroups. Trends of OAC users' characteristics, expenditure, and number of prescriptions were evaluated using the Mann-Kendall test for trends.

RESULTS

Between 2014 and 2020, the number of warfarin users decreased from 3.8 million (70% of all OAC users) to 2.2 million (p = 0.007) [29% of all OAC users], while the number of DOAC users increased from 1.6 million (30% of all OAC users) to 5.4 million (p = 0.003) [70% of all OAC users]. The total expenditure of OACs in the US increased from $3.4 billion in 2014 to $17.8 billion in 2020 (p = 0.003), which was driven by the increase in DOAC expenditures (p = 0.003).

CONCLUSIONS

DOACs have replaced warfarin as the preferred OAC in the US. The increased costs associated with DOAC use may decline when generic formulations are approved.

Development of supramolecular anticoagulants with on-demand reversibility

Drugs are administered at a dosing schedule set by their therapeutic index, and termination of action is achieved by clearance and metabolism of the drug. In some cases, such as anticoagulant drugs or immunotherapeutics, it is important to be able to quickly reverse the drug's action. Here, we report a general strategy to achieve on-demand reversibility by designing a supramolecular drug (a noncovalent assembly of two cooperatively interacting drug fragments held together by transient hybridization of peptide nucleic acid (PNA)) that can be reversed with a PNA antidote that outcompetes the hybridization between the fragments. We demonstrate the approach with thrombin-inhibiting anticoagulants, creating very potent and reversible bivalent direct thrombin inhibitors (Ki = 74 pM). The supramolecular inhibitor effectively inhibited thrombus formation in mice in a needle injury thrombosis model, and this activity could be reversed by administration of the PNA antidote. This design is applicable to therapeutic targets where two binding sites can be identified.

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.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society (HRS), the Asia Pacific HRS, and the Latin American HRS.

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.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society .

Being precise with anticoagulation to reduce adverse drug reactions: are we there yet?

Anticoagulants are potent therapeutics widely used in medical and surgical settings, and the amount spent on anticoagulation is rising. Although warfarin remains a widely prescribed oral anticoagulant, prescriptions of direct oral anticoagulants (DOACs) have increased rapidly. Heparin-based parenteral anticoagulants include both unfractionated and low molecular weight heparins (LMWHs). In clinical practice, anticoagulants are generally well tolerated, although interindividual variability in response is apparent. This variability in anticoagulant response can lead to serious incident thrombosis, haemorrhage and off-target adverse reactions such as heparin-induced thrombocytopaenia (HIT). This review seeks to highlight the genetic, environmental and clinical factors associated with variability in anticoagulant response, and review the current evidence base for tailoring the drug, dose, and/or monitoring decisions to identified patient subgroups to improve anticoagulant safety. Areas that would benefit from further research are also identified. Validated variants in VKORC1, CYP2C9 and CYP4F2 constitute biomarkers for differential warfarin response and genotype-informed warfarin dosing has been shown to reduce adverse clinical events. Polymorphisms in CES1 appear relevant to dabigatran exposure but the genetic studies focusing on clinical outcomes such as bleeding are sparse. The influence of body weight on LMWH response merits further attention, as does the relationship between anti-Xa levels and clinical outcomes. Ultimately, safe and effective anticoagulation requires both a deeper parsing of factors contributing to variable response, and further prospective studies to determine optimal therapeutic strategies in identified higher risk subgroups.

How the Hemostasis Laboratory Can Help Clinicians to Manage Patients on Oral Anticoagulants

Oral anticoagulants are widely used to treat or prevent cardiovascular diseases in millions of patients worldwide. They are the drugs of choice for stroke prevention and systemic embolism in patients with non-valvular atrial fibrillation and prosthetic heart valves, as well as for treatment/prevention of venous thromboembolism. Oral anticoagulants include vitamin K antagonists (VKAs) and direct oral anticoagulants (DOACs). The hemostasis laboratory plays a crucial role in the management of treated patients, spanning from dose adjustment based on laboratory testing that applies to VKAs to the measurement of drug concentrations in special situations that apply to DOACs. This article aims to overview how the hemostasis laboratory can help clinicians manage patients on oral anticoagulants. Special interest is devoted to the international normalized ratio, used to manage patients on VKAs and to the measurement of DOAC concentrations, for which the role of the laboratory is still not very well defined, and most interferences of DOACs with some of the most common hemostatic parameters are not widely appreciated.

Anticoagulation for Atrial Fibrillation: A Review of Current Literature and Views

Atrial fibrillation is a common supraventricular tachyarrhythmia with uncoordinated atrial activation and ineffective atrial contraction. This leads to an increased risk of atrial thrombi, most commonly in the left atrial appendage, and increased risks of embolic strokes and/or peripheral thromboembolism. It is associated with significant morbidity and mortality. To meet the concerns of thrombi and stroke, anticoagulation has been the mainstay for prevention and treatment thereof. Historically, anticoagulation involved the use of aspirin or vitamin K antagonists, mainly warfarin. Since early 2010s, direct oral anticoagulants (DOACs) including dabigatran, rivaroxaban, apixaban, and edoxaban have been introduced and approved for anticoagulation of atrial fibrillation. DOACs demonstrated a dramatic reduction in the rate of intracranial hemorrhage as compared to warfarin, and offer the advantages of absolution of monitoring therefore avoid the risk of hemorrhages in the context of narrow therapeutic window and under-treatment characteristic of warfarin, particularly in high-risk patients. One major concern and disadvantage for DOACs was lack of reversal agents, which have largely been ameliorated by the approval of Idarucizumab for dabigatran and Andexanet alfa for both apixaban and rivaroxaban, with Ciraparantag as a universal reversal agent for all DOACs undergoing Fast-Track Review from FDA. In this article, we will be providing a broad review of anticoagulation for atrial fibrillation with a focus on risk stratification schemes and anticoagulation agents (warfarin, aspirin, DOACs) including special clinical considerations.

Effect of direct oral anticoagulants on bleeding during and after cataract surgery

PURPOSE

To assess the risk for intraoperative and postoperative ocular bleeding associated with direct oral anticoagulant treatment in patients undergoing phacoemulsification surgery.

METHODS

Consecutive patients had phacoemulsification and intraocular lens implantation while taking uninterrupted direct oral anticoagulants (dabigatran, rivaroxaban, or apixaban). Gender and age-matched patients without antithrombotic therapy were used as the control group. Patients were examined one week postoperatively. Intraoperative and postoperative hemorrhagic and non-hemorrhagic complications were assessed.

RESULTS

Forty patients (56 eyes) on direct oral anticoagulants and 120 patients (172 eyes) without anticoagulation, at a mean age of 77 years, had phacoemulsification. There was no significant difference between the groups in the rate of intraoperative and postoperative bleeding. One eye (1.8%) in the treatment group and 3 eyes (1.7%) in the control group had hyphema (p = 0.72). No patient had thromboembolic event during or after surgery.

CONCLUSIONS

Cataract surgery was safely performed while continuing direct oral anticoagulation.

Time to Anticoagulation Reversal and Outcomes After Intracerebral Hemorrhage

Importance

Intracerebral hemorrhage (ICH) is the deadliest stroke subtype, and mortality rates are especially high in anticoagulation-associated ICH. Recently, specific anticoagulation reversal strategies have been developed, but it is not clear whether there is a time-dependent treatment effect for door-to-treatment (DTT) times in clinical practice.

Objective

To evaluate whether DTT time is associated with outcome among patients with anticoagulation-associated ICH treated with reversal interventions.

Design, Setting, and Participants

This cohort study used data from the American Heart Association Get With The Guidelines-Stroke quality improvement registry. Patients with ICH who presented within 24 hours of symptom onset across 465 US hospitals from 2015 to 2021 were included. Data were analyzed from January to September 2023.

Exposures

Anticoagulation-associated ICH.

Main Outcomes and Measures

DTT times and outcomes were analyzed using logistic regression modeling, adjusted for demographic, history, baseline, and hospital characteristics, with hospital-specific random intercepts to account for clustering by site. The primary outcome of interest was the composite inpatient mortality and discharge to hospice. Additional prespecified secondary outcomes, including functional outcome (discharge modified Rankin Scale score, ambulatory status, and discharge venue), were also examined.

Results

Of 9492 patients with anticoagulation-associated ICH and documented reversal intervention status, 4232 (44.6%) were female, and the median (IQR) age was 77 (68-84) years. A total of 7469 (78.7%) received reversal therapy, including 4616 of 5429 (85.0%) taking warfarin and 2856 of 4069 (70.2%) taking a non-vitamin K antagonist oral anticoagulant. For the 5224 patients taking a reversal intervention with documented workflow times, the median (IQR) onset-to-treatment time was 232 (142-482) minutes and the median (IQR) DTT time was 82 (58-117) minutes, with a DTT time of 60 minutes or less in 1449 (27.7%). A DTT time of 60 minutes or less was associated with decreased mortality and discharge to hospice (adjusted odds ratio, 0.82; 95% CI, 0.69-0.99) but no difference in functional outcome (ie, a modified Rankin Scale score of 0 to 3; adjusted odds ratio, 0.91; 95% CI, 0.67-1.24). Factors associated with a DTT time of 60 minutes or less included White race, higher systolic blood pressure, and lower stroke severity.

Conclusions and Relevance

In US hospitals participating in Get With The Guidelines-Stroke, earlier anticoagulation reversal was associated with improved survival for patients with ICH. These findings support intensive efforts to accelerate evaluation and treatment for patients with this devastating form of stroke.

Prothrombin Complex Concentrate vs Conservative Management in ICH Associated With Direct Oral Anticoagulants

Importance

Intracerebral hemorrhage (ICH) associated with direct oral anticoagulant (DOAC) use carries extremely high morbidity and mortality. The clinical effectiveness of hemostatic therapy is unclear.

Objective

To compare the clinical and radiological outcomes of DOAC-associated ICH treated with prothrombin complex concentrate (PCC) vs conservative management.

Design, Setting, and Participants

In this population-based, propensity score-weighted retrospective cohort study, patients who developed DOAC-associated ICH from January 1, 2016, to December 31, 2021, in Hong Kong were identified. The outcomes of patients who received 25 to 50 IU/kg PCC with those who received no hemostatic agents were compared. Data were analyzed from May 1, 2022, to June 30, 2023.

Main Outcomes and Measures

The primary outcome was modified Rankin scale of 0 to 3 or returning to baseline functional status at 3 months. Secondary outcomes were mortality at 90 days, in-hospital mortality, and hematoma expansion. Weighted logistic regression was performed to evaluate the association of PCC with study outcomes. In unweighted logistic regression models, factors associated with good neurological outcome and hematoma expansion in DOAC-associated ICH were identified.

Results

A total of 232 patients with DOAC-associated ICH, with a mean (SD) age of 77.2 (9.3) years and 101 (44%) female patients, were included. Among these, 116 (50%) received conservative treatment and 102 (44%) received PCC. Overall, 74 patients (31%) patients had good neurological recovery and 92 (39%) died within 90 days. Median (IQR) baseline hematoma volume was 21.7 mL (3.6-66.1 mL). Compared with conservative management, PCC was not associated with improved neurological recovery (adjusted odds ratio [aOR], 0.62; 95% CI, 0.33-1.16; P = .14), mortality at 90 days (aOR, 1.03; 95% CI, 0.70-1.53; P = .88), in-hospital mortality (aOR, 1.11; 95% CI, 0.69-1.79; P = .66), or reduced hematoma expansion (aOR, 0.94; 95% CI, 0.38-2.31; P = .90). Higher baseline hematoma volume, lower Glasgow coma scale, and intraventricular hemorrhage were associated with lower odds of good neurological outcome but not hematoma expansion.

Conclusions and Relevance

In this cohort study, Chinese patients with DOAC-associated ICH had large baseline hematoma volumes and high rates of mortality and functional disability. PCC treatment was not associated with improved functional outcome, hematoma expansion, or mortality. Further studies on novel hemostatic agents as well as neurosurgical and adjunctive medical therapies are needed to identify the best management algorithm for DOAC-associated ICH.

Non-vitamin-K-antagonist oral anticoagulants (NOACs) after acute myocardial infarction: a network meta-analysis

BACKGROUND

Balancing the risk of bleeding and thrombosis after acute myocardial infarction (AMI) is challenging, and the optimal antithrombotic therapy remains uncertain. The potential of non-vitamin K antagonist oral anticoagulants (NOACs) to prevent ischaemic cardiovascular events is promising, but the evidence remains limited.

OBJECTIVES

To evaluate the efficacy and safety of non-vitamin-K-antagonist oral anticoagulants (NOACs) in addition to background antiplatelet therapy, compared with placebo, antiplatelet therapy, or both, after acute myocardial infarction (AMI) in people without an indication for anticoagulation (i.e. atrial fibrillation or venous thromboembolism).

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, the Conference Proceedings Citation Index - Science, and two clinical trial registers in September 2022 with no language restrictions. We checked the reference lists of included studies for any additional trials.

SELECTION CRITERIA

We searched for randomised controlled trials (RCTs) that evaluated NOACs plus antiplatelet therapy versus placebo, antiplatelet therapy, or both, in people without an indication for anticoagulation after an AMI.

DATA COLLECTION AND ANALYSIS

Two review authors independently checked the results of searches to identify relevant studies, assessed each included study, and extracted study data. We conducted random-effects pairwise analyses using Review Manager Web, and network meta-analysis using the R package 'netmeta'. We ranked competing treatments by P scores, which are derived from the P values of all pairwise comparisons and allow ranking of treatments on a continuous 0-to-1 scale.

MAIN RESULTS

We identified seven eligible RCTs, including an ongoing trial that we could not include in the analysis. Of the six RCTs involving 33,039 participants, three RCTs compared rivaroxaban with placebo, two RCTs compared apixaban with placebo, and one RCT compared dabigatran with placebo. All participants in the six RCTs received concomitant antiplatelet therapy. The available evidence suggests that rivaroxaban compared with placebo reduces the rate of all-cause mortality (risk ratio (RR) 0.82, 95% confidence interval (CI) 0.69 to 0.98; number needed to treat for an additional beneficial outcome (NNTB) 250; 3 studies, 21,870 participants; high certainty) and probably reduces cardiovascular mortality (RR 0.83, 95% CI 0.69 to 1.01; NNTB 250; 3 studies, 21,870 participants; moderate certainty). There is probably little or no difference between apixaban and placebo in all-cause mortality (RR 1.09, 95% CI 0.88 to 1.35; number needed to treat for an additional harmful outcome (NNTH) 334; 2 studies, 8638 participants; moderate certainty) and cardiovascular mortality (RR 0.99, 95% CI 0.77 to 1.27; number needed to treat not applicable; 2 studies, 8638 participants; moderate certainty). Dabigatran may reduce the rate of all-cause mortality compared with placebo (RR 0.57, 95% CI 0.31 to 1.06; NNTB 63; 1 study, 1861 participants; low certainty). Dabigatran compared with placebo may have little or no effect on cardiovascular mortality, although the point estimate suggests benefit (RR 0.72, 95% CI 0.34 to 1.52; NNTB 143; 1 study, 1861 participants; low certainty). Two of the investigated NOACs were associated with an increased risk of major bleeding compared to placebo: apixaban (RR 2.41, 95% CI 1.44 to 4.06; NNTH 143; 2 studies, 8544 participants; high certainty) and rivaroxaban (RR 3.31, 95% CI 1.12 to 9.77; NNTH 125; 3 studies, 21,870 participants; high certainty). There may be little or no difference between dabigatran and placebo in the risk of major bleeding (RR 1.74, 95% CI 0.22 to 14.12; NNTH 500; 1 study, 1861 participants; low certainty). The results of the network meta-analysis were inconclusive between the different NOACs at all individual doses for all primary outcomes. However, low-certainty evidence suggests that apixaban (combined dose) may be less effective than rivaroxaban and dabigatran for preventing all-cause mortality after AMI in people without an indication for anticoagulation.

AUTHORS' CONCLUSIONS

Compared with placebo, rivaroxaban reduces all-cause mortality and probably reduces cardiovascular mortality after AMI in people without an indication for anticoagulation. Dabigatran may reduce the rate of all-cause mortality and may have little or no effect on cardiovascular mortality. There is probably no meaningful difference in the rate of all-cause mortality and cardiovascular mortality between apixaban and placebo. Moreover, we found no meaningful benefit in efficacy outcomes for specific therapy doses of any investigated NOACs following AMI in people without an indication for anticoagulation. Evidence from the included studies suggests that rivaroxaban and apixaban increase the risk of major bleeding compared with placebo. There may be little or no difference between dabigatran and placebo in the risk of major bleeding. Network meta-analysis did not show any superiority of one NOAC over another for our prespecified primary outcomes. Although the evidence suggests that NOACs reduce mortality, the effect size or impact is small; moreover, NOACs may increase major bleeding. Head-to-head trials, comparing NOACs against each other, are required to provide more solid evidence.

Dabigatran pharmacokinetic-pharmacodynamic in sheep: Informing dose for anticoagulation during cardiopulmonary bypass

BACKGROUND

The effect of the anticoagulant, dabigatran, and its antagonist, idarucizumab, on coagulation remains poorly quantified. There are few pharmacokinetic-pharmacodynamic data available to determine dabigatran dose in humans or animals undergoing cardiopulmonary bypass.

METHODS

Five sheep were given intravenous dabigatran 4 mg/kg. Blood samples were collected for thromboelastometric reaction time (R-time) and drug assay at 5, 15, 30, 60, 120, 240, 480 min, and 24 h. Plasma dabigatran concentrations and R-times were analyzed using an integrated pharmacokinetic-pharmacodynamic model using non-linear mixed effects. The impact of idarucizumab 15 mg/kg administered 120 min after dabigatran 4 mg/kg and its effect on R-time was observed.

RESULTS

A 2-compartment model described dabigatran pharmacokinetics with a clearance (CL 0.0453 L/min/70 kg), intercompartment clearance (Q 0.268 L/min/70 kg), central volume of distribution (V1 2.94 L/70 kg), peripheral volume of distribution (V2 9.51 L/70 kg). The effect compartment model estimates for a sigmoid EMAX model using Reaction time had an effect site concentration (Ce50 64.2 mg/L) eliciting half of the maximal effect (EMAX 180 min). The plasma-effect compartment equilibration half time (T1/2keo) was 1.04 min. Idarucizumab 15 mg/kg reduced R-time by approximately 5 min.

CONCLUSIONS

Dabigatran reversibly binds to the active site on the thrombin molecule, preventing activation of coagulation factors. The pharmacologic target concentration strategy uses pharmacokinetic-pharmacodynamic information to inform dose. A loading dose of dabigatran 0.25 mg/kg followed by a maintenance infusion of dabigatran 0.0175 mg/kg/min for 30 min and a subsequent infusion dabigatran 0.0075 mg/kg/min achieves a steady state target concentration of 5 mg/L in a sheep model.

Human Dose and Pharmacokinetic Predictions for Biologics at Boehringer Ingelheim: A Retrospective Analysis

INTRODUCTION

Accurate predictions of pharmacokinetics and efficacious doses for biologics in humans are critical for selecting appropriate first-in-human starting doses and dose ranges and for estimating clinical material needs and cost of goods. This also impacts clinical feasibility, particularly for subcutaneously administered biologics.

METHODS

We performed a comprehensive comparison between predicted and observed clearances and doses in humans for a set of 22 biologic drugs developed at Boehringer Ingelheim (BI) over the last 2 decades. The analysis included biologics across three therapeutic areas comprising a wide variety of modalities: mono- and bispecific monoclonal antibodies (mAbs) and nanobodies and a Fab fragment.

RESULTS

Our analysis showed that observed clearances in humans were within twofold of predicted clearances for 17 out of 20 biologics (85%). Six biologics had uncharacteristically high observed human clearances (range 32-280 mL/h) for their respective molecular classes, impacting their clinical developability. For three molecules, molecular characteristics contributed to the high clearance. Clinically selected doses were within twofold of predicted for 58% of projects. With 42% and 25% of projects selecting clinical doses higher than two- or threefold the predicted value, respectively, the importance of better understanding not only the pharmacokinetic (PK) but also the predictivity of pharmacodynamic models is highlighted.

CONCLUSIONS

We provide a clinical pharmacology perspective on the commonly accepted twofold range of human clearance predictions as well as the implications of higher than predicted targeted efficacious plasma concentration on clinical development. Finally, an analysis of key success factors for biologics at BI was conducted, which may be relevant for the entire pharmaceutical industry. This is one of the largest retrospective analyses for biologics and provides further evidence that successful predictions of human PK and efficacious dose will be further facilitated by gathering key translational data early in research.

[The multidirectional effects of thrombin and the possibility of their control in neurology]

The review presents the main physiological functions of thrombin. The procoagulant and anticoagulant activities of the key serine protease are discussed in both physiological and pathological conditions of hemostasis. The involvement of thrombin in atherogenesis, as well as its role as a mediator of vascular dysfunction and inflammation in both the peripheral and central nervous system, is highlighted. A pronounced imbalance between the pro- and anticoagulant systems leads to an increase in thrombin formation and creates conditions for the development of thrombosis. Tests that allow direct or indirect assessment of thrombin's functional activity are presented. The potential applications of direct thrombin inhibitors and direct blockers of thrombin PAR receptors in vascular neurology are also considered.

Direct Oral Anticoagulants in Special Patient Populations

Anticoagulants are a cornerstone of treatment in atrial fibrillation. Nowadays, direct oral anticoagulants (DOACs) are extensively used for this condition in developed countries. However, DOAC treatment may be inappropriate in certain patient populations, such as: patients with chronic kidney disease in whom DOAC concentrations may be dangerously elevated; frail elderly patients with an increased risk of falls; patients with significant drug-drug interactions (DDI) affecting either DOAC concentration or effect; patients at the extremes of body mass in whom an "abnormal" volume of distribution may result in inappropriate drug concentrations; patients with recurrent stroke reflecting an unusually high thromboembolic tendency; and, lastly, patients who experience major hemorrhage on an anticoagulant and in whom continued anticoagulation is deemed necessary. Herein we provide a fictional case-based approach to review the recommendations for the use of DOACs in these special patient populations.

Idarucizumab for Emergency Reversal of the Anticoagulant Effects of Dabigatran: Final Results of a Japanese Postmarketing Surveillance Study

INTRODUCTION

Idarucizumab, a monoclonal antibody fragment that rapidly reverses the anticoagulant effects of dabigatran, was approved in Japan in September 2016, at which time an all-case, postmarketing surveillance (PMS) study was initiated to collect data on idarucizumab in Japanese patients. Interim results were published previously, and the final results are reported herein.

METHODS

This multicenter, open-label, uncontrolled, non-interventional PMS study was conducted in Japanese patients who received idarucizumab at the approved dose (2 × 2.5 g/50 ml) and had uncontrolled bleeding (group A) or required an emergency procedure (group B). The primary endpoint was the frequency of adverse drug reactions (ADRs). The secondary endpoint was the maximum extent of reversal of the anticoagulant effects of dabigatran, within 4 h of idarucizumab administration, based on activated partial thromboplastin time (aPTT).

RESULTS

The final analysis included 804 patients. ADRs during the idarucizumab treatment and post-treatment periods were reported in 17 of 542 patients (3.1%) in group A and 12 of 240 patients (5.0%) in group B. Thrombotic events were reported in 22 patients (4.1%) in group A and 15 patients (6.3%) in group B, and hypersensitivity occurred in four (0.7%) and five patients (2.1%), respectively. Among 793 patients evaluated for effectiveness, 78 in group A and 26 in group B had aPTT data at baseline (immediately before idarucizumab administration) and within 4 h of idarucizumab administration; in these patients, median maximum percentage reversal within 4 h of idarucizumab administration was 100%.

CONCLUSIONS

The final analysis from the PMS study confirms previous findings suggesting that idarucizumab can safely and effectively reverse the anticoagulant effects of dabigatran in Japanese patients in clinical practice. The results support the continued use of idarucizumab in Japan.

TRIAL REGISTRATION

This study is registered with ClinicalTrials.gov (NCT02946931).

Resuscitation and Preparation of the Emergency General Surgery Patient

Traditionally, the workflow surrounding a general surgery patient allows for a period of evaluation and optimization of underlying medical issues to allow for risk modification; however, in the emergency, this optimization period is largely condensed because of its time-dependent nature. Because the lack of optimization can lead to complications, the ability to rapidly resuscitate the patient, proceed to procedural intervention to control the situation, and manage common medical comorbidities is paramount. This article provides an overview on these subjects.

Royal College of Ophthalmologists' National Ophthalmology Database study of cataract surgery: report 11, techniques and complications of local anesthesia for cataract surgery in the United Kingdom

PURPOSE

To describe variation in local anesthesia techniques and complications over a 10-year period for cataract surgery in the United Kingdom.

SETTING

Reporting centers to the Royal College of Ophthalmologists (RCOphth) National Ophthalmology Database (NOD).

DESIGN

Retrospective cross-sectional register-based study.

METHODS

Data from the RCOphth NOD were used. Eligible for analysis were 1 195 882 cataract operations performed using local anesthesia between April 1, 2010, and March 31, 2020, in 80 centers.

RESULTS

Overall, topical anesthesia alone was used in 152 321 operations (12.7%), combined topical and intracameral in 522 849 (43.7%), sub-Tenon in 461 175 (38.6%), and peribulbar/retrobulbar in 59 537 (5.0%). In National Health Service (NHS) institutions, 48.3% of operations were topical with/without intracameral vs 88.7% in independent sector treatment centers (ISTCs). 45.9% were sub-Tenon in NHS vs 9.6% in ISTCs. 5.8% were peribulbar/retrobulbar in NHS vs 1.7% in ISTCs. Anesthetic complication rates decreased from 2.7% in the 2010 NHS year to 1.5% in the 2019 NHS year (overall, 2.1% for NHS; 0.2% for ISTCs). Overall anesthetic complication rates were 0.3%, 0.3%, 3.5%, and 3.1% for topical alone, combined topical/intracameral, sub-Tenon, and peribulbar/retrobulbar, respectively. Complication rates were higher for sharp-needle anesthesia (peribulbar/retrobulbar) in patients taking warfarin rather than direct oral anticoagulants (4.8% vs 3.1%; P = .024). Considerable variation was observed between centers on anesthetic choices and anesthetic complication rates.

CONCLUSIONS

Combined topical and intracameral is the most common choice of anesthesia for cataract surgery in the United Kingdom and is associated with lower anesthetic-related complication rates than sub-Tenon and peribulbar/retrobulbar anesthesia. Variation in the anesthetic choice exists between centers and between NHS and ISTC sectors.

Novel strategies in antithrombotic therapy: targeting thrombosis while preserving hemostasis

Antithrombotic therapy is a delicate balance between the benefits of preventing a thrombotic event and the risks of inducing a major bleed. Traditional approaches have included antiplatelet and anticoagulant medications, require careful dosing and monitoring, and all carry some risk of bleeding. In recent years, several new targets have been identified, both in the platelet and coagulation systems, which may mitigate this bleeding risk. In this review, we briefly describe the current state of antithrombotic therapy, and then present a detailed discussion of the new generation of drugs that are being developed to target more safely existing or newly identified pathways, alongside the strategies to reverse direct oral anticoagulants, showcasing the breadth of approaches. Combined, these exciting advances in antithrombotic therapy bring us closer than we have ever been to the "holy grail" of the field, a treatment that separates the hemostatic and thrombotic systems, preventing clots without any concurrent bleeding risk.

Optimal management of cardiac surgery patients using direct oral anticoagulants: recommendations for clinical practice

OBJECTIVES

Literature is scarce on the management of patients using direct oral anticoagulants (DOACs) undergoing elective, urgent and emergency surgery. Therefore, we summarize the current evidence and provide literature-based recommendations for the management of patients on DOACs in the perioperative phase.

METHODS

A general literature review was conducted on the pharmacology of DOACs and for recommendations on the management of cardiac surgical patients on DOACs. Additionally, we performed a systematic review for studies on the use of direct DOAC reversal agents in the emergency cardiac surgical setting.

RESULTS

When surgery is elective, the DOAC cessation strategy is relatively straightforward and should be adapted to the renal function. The same approach applies to urgent cases, but additional DOAC activity drug level monitoring tests may be useful. In emergency cases, idarucizumab can be safely administered to patients on dabigatran in any of the perioperative phases. However, andexanet alfa, which is not registered for perioperative use, should not be administered in the preoperative phase to reverse the effect of factor Xa inhibitors, as it may induce temporary heparin resistance. Finally, the administration of (activated) prothrombin complex concentrate may be considered in all patients on DOACs, and such concentrates are generally readily available.

CONCLUSIONS

DOACs offer several advantages over vitamin K antagonists, but care must be taken in patients undergoing cardiac surgery. Although elective and urgent cases can be managed relatively straightforwardly, the management of emergency cases requires particular attention.

Inhibition of Factor XI: A New Era in the Treatment of Venous Thromboembolism in Cancer Patients?

Direct oral anticoagulants against activated factor X and thrombin were the last milestone in thrombosis treatment. Step by step, they replaced antivitamin K and heparins in most of their therapeutic indications. As effective as the previous anticoagulant, the decreased but persistent risk of bleeding while using direct oral anticoagulants has created space for new therapeutics aiming to provide the same efficacy with better safety. On this basis, drug targeting factor XI emerged as an option. In particular, cancer patients might be one of the populations that will most benefit from this technical advance. In this review, after a brief presentation of the different factor IX inhibitors, we explore the potential benefit of this new treatment for cancer patients.

New High-Affinity Thrombin Aptamers for Advancing Coagulation Therapy: Balancing Thrombin Inhibition for Clot Prevention and Effective Bleeding Management with Antidote

Thrombin is a key enzyme involved in blood clotting, and its dysregulation can lead to thrombotic diseases such as stroke, myocardial infarction, and deep vein thrombosis. Thrombin aptamers have the potential to be used as therapeutic agents to prevent or treat thrombotic diseases. Thrombin DNA aptamers developed in our laboratory exhibit high affinity and specificity to thrombin. In vitro assays have demonstrated their efficacy by significantly decreasing Factor II activity and increasing PT and APTT times in both plasma and whole blood. Aptamers AYA1809002 and AYA1809004, the two most potent aptamers, exhibit high affinity for their target, with affinity constants (Kd) of 10 nM and 13 nM, respectively. Furthermore, the in vitro activity of these aptamers displays dose-dependent behavior, highlighting their efficacy in a concentration-dependent manner. In vitro stability assessments reveal that the aptamers remain stable in plasma and whole blood for up to 24 h. This finding is crucial for their potential application in clinical settings. Importantly, the thrombin inhibitory activity of the aptamers can be reversed by employing reverse complement sequences, providing a mechanism to counteract their anticoagulant effects when necessary to avoid excessive bleeding. These thrombin aptamers have been determined to be safe, with no observed mutagenic or immunogenic effects. Overall, these findings highlight the promising characteristics of these newly developed thrombin DNA aptamers, emphasizing their potential for therapeutic applications in the field of anticoagulation therapy. Moreover, the inclusion of an antidote in the coagulation therapy regimen can improve patient safety, ensure greater therapeutic efficacy, and minimize risk during emergency situations.

Stroke Around Pregnancy; Protection and Prevention!

As per recent studies, incidence of stroke is increasing in pregnant women. It is essential to be vigilant and well-versed in managing stroke in pregnancy, as both the mother and the baby are prone to stroke-related injury. In this viewpoint article, we have reviewed the current data from research publications on the incidence, prevalence, risk factors, and clinical presentation of stroke in pregnancy. Finally, we have discussed the plan of investigations and the current treatment guidelines for stroke in pregnancy.

Exploring safety and efficacy of rivaroxaban after living donor liver transplantation: a retrospective study

PURPOSE

Thromboembolic complications remain a significant concern in postoperative patients, particularly those who have undergone liver transplantation. Warfarin has been the standard oral anticoagulant. Direct oral anticoagulants (DOACs) have several advantages over warfarin, including rapid onset of action and standardized dose guidelines. We aimed to assess the safety of rivaroxaban in living donor liver transplantation (LDLT) recipients.

METHODS

This study was a single-center, retrospective descriptive analysis of LDLT recipients who received rivaroxaban between December 2020 and April 2022. A total of 27 recipients received rivaroxaban postoperatively. Liver function tests, immunosuppression levels, serum creatinine, and INR were recorded before the initiation of rivaroxaban and then on post-therapy days 1, 7, 14, 28, 90, and 180.

RESULTS

Among the 27 recipients receiving rivaroxaban postoperatively, portal venous thrombosis was the most prevalent indication for anticoagulation (44.4%), followed by Budd-Chiari syndrome (29.6%). Nine patients had a twofold increase in either ALT or AST values, two of whom were treated for biliary strictures and the others for rejection. Eighteen patients were given tacrolimus, and eight were on cyclosporine, with one patient switched from tacrolimus to cyclosporine due to insufficient therapeutic levels. There were no incidents of bleeding or re-thrombosis during the 180-day follow-up period.

CONCLUSION

Rivaroxaban may be a safe and effective alternative in LDLT recipients with no significant adverse incidents. Further studies with larger sample sizes are needed to confirm these findings and determine this population's optimal dose and duration of rivaroxaban therapy.

Immune-based Therapies-What the Emergency Physician Needs to Know

Immunotherapy is a treatment modality that has a broad and rapidly growing range of applications to treat both chronic and acute diseases, including rheumatoid arthritis, Crohn disease, cancer, and COVID-19. Emergency physicians must be aware of the breadth of applications and be able to consider the effects of immunotherapies when patients on these treatments present to the hospital. This article provides a review of the mechanisms of action, indications for use, and potential complications of immunotherapy treatments that are relevant in the emergency care setting.

Antibody-Drug Conjugates: A Review of Approved Drugs and Their Clinical Level of Evidence

Antibody-drug conjugates (ADCs) are an innovative family of agents assembled through linking cytotoxic drugs (payloads) covalently to monoclonal antibodies (mAbs) to be delivered to tumor tissue that express their particular antigen, with the theoretical advantage of an augmented therapeutic ratio. As of June 2023, eleven ADCs have been approved by the Food and Drug Administration (FDA) and are on the market. These drugs have been added to the therapeutic armamentarium of acute myeloblastic and lymphoblastic leukemias, various types of lymphoma, breast, gastric or gastroesophageal junction, lung, urothelial, cervical, and ovarian cancers. They have proven to deliver more potent and effective anti-tumor activities than standard practice in a wide variety of indications. In addition to targeting antigen-expressing tumor cells, bystander effects have been engineered to extend cytotoxic killing to low-antigen-expressing or negative tumor cells in the heterogenous tumor milieu. Inevitably, myelosuppression is a common side effect with most of the ADCs due to the effects of the cytotoxic payload. Also, other unique side effects are specific to the tissue antigen that is targeted for, such as the cardiac toxicity with Her-2 targeting ADCs, and the hemorrhagic side effects with the tissue factor (TF) targeting Tisotumab vedotin. Further exciting developments are centered in the strategies to improve the tolerability and efficacy of the ADCs to improve the therapeutic window; as well as the development of novel payloads including (1) peptide-drug conjugates (PDCs), with the peptide replacing the monoclonal antibody, rendering greater tumor penetration; (2) immune-stimulating antibody conjugates (ISACs), which upon conjugation of the antigen, cause an influx of pro-inflammatory cytokines to activate dendritic cells and harness an anti-tumor T-cell response; and (3) the use of radioactive isotopes as a payload to enhance cytotoxic activity.

Atrial Fibrillation

Evidence for diagnosis and treatment of atrial fibrillation (AF) has expanded substantially since 2017, when In the Clinic last considered this subject. Direct oral anticoagulants have become the predominant therapy for thromboembolic disease, and antidotes for these drugs are now available. Device-based left atrial appendage occlusion is frequently used in patients who cannot tolerate systemic anticoagulation, and growing evidence suggests that early rhythm control improves outcomes. Catheter ablation is now frequently performed to prevent recurrent AF. Managing risk factors for AF, such as hypertension, diabetes, and obesity, remains paramount in prevention of this condition.

Direct oral anticoagulants or vitamin K antagonists in emergencies: comparison of management in an observational study

Background

Restoring hemostasis in patients on oral anticoagulants presenting with major hemorrhage (MH) or before surgical intervention has changed, with the replacement of vitamin K antagonist (VKA) with direct oral anticoagulants (DOACs).

Objectives

To observe the difference in urgent hemostatic management between patients on VKA and those on DOACs.

Methods

A multicenter observational study evaluated the variation in laboratory testing, hemostatic management, mortality, and hospital length of stay (LOS) in patients on VKA or DOACs presenting with MH or urgent hemostatic restoration.

Results

Of the 1194 patients analyzed, 783 had MH (61% VKA) and 411 required urgent hemostatic restoration before surgery (56% VKA). Compared to the international normalized ratio (97.6%), plasma DOAC levels were measured less frequently (<45%), and the time taken from admission for the coagulation sample to reach the laboratory varied widely (median, 52.3 minutes; IQR, 24.8-206.7). No significant plasma DOAC level (<50 ng/mL) was found in up to 19% of patients. There was a poor relationship between plasma DOAC level and the usage of a hemostatic agent. When compared with patients receiving VKA (96.5%) or dabigatran (93.7%), fewer patients prescribed a factor Xa inhibitor (75.5%) received a prohemostatic reversal agent. The overall 30-day mortality for MH (mean: 17.8%) and length of stay (LOS) (median: 8.7 days) was similar between VKA and DOAC patients.

Conclusion

In DOAC patients, when compared to those receiving VKA, plasma DOAC levels were measured less frequently than the international normalized ratio and had a poor relationship with administering a hemostatic reversal agent. In addition, following MH, mortality and LOS were similar between VKA and DOAC patients.

Perioperative Management of Anticoagulant and Antiplatelet Therapy

Anticoagulant and Antiplatelet Drug ManagementManagement of patients on an anticoagulant or antiplatelet drug who require surgery or an invasive procedure is a common clinical problem. Douketis and Spyropoulos provide an evidence-based but practical approach to managing anticoagulants and antiplatelet drugs in the perioperative setting.

Clinical Studies with Anticoagulants that Have Changed Clinical Practice

Anticoagulant therapy is the cornerstone of treatment and prevention of arterial and venous thromboembolism. Taking a historical perspective, starting in the 1960s, and progressing through to 2022, we discuss key clinical trials of anticoagulants that have changed clinical practice, and examine obstacles encountered in bringing these anticoagulants to the clinic. The design of some of the early studies that shaped clinical practice was poor by current standards, but their results were influential because nothing better was available. Both heparin and vitamin K antagonists had been in clinical use for several decades before well-designed trials in the 1980s optimized their dosing and enhanced their safety and efficacy. Low-molecular-weight heparin then replaced unfractionated heparin because it had a more predictable dose-response and a longer half-life, thereby allowing it to be used conveniently in out-of-hospital settings. More recently, direct oral anticoagulants became the oral anticoagulants of choice for most indications because they were shown to be at least as safe and effective as vitamin K antagonists when used in fixed doses without the need for laboratory monitoring. The design of the trials that led to the approval of the direct oral anticoagulants was excellent, but further studies are required to optimize their dosing in selected patients who were underrepresented in these trials.

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

BACKGROUND

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

DESIGN

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

RESULTS

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

DISCUSSION

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

CONCLUSION

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

Novel Antithrombotic Agents in Pregnancy Anticoagulants and Antiplatelet Agents

Increasing rates of thromboembolic complications have required increasing use of anticoagulant and antiplatelet agents during and after pregnancy. Furthermore, thromboembolism is both a cause and a complication of severe maternal morbidity requiring intensive care. As a consequence, almost all patients admitted to intensive care units receive an anticoagulant or an antiplatelet agent (or both) for either treatment or prevention of thromboembolism. In this review, we summarize commonly used anticoagulants and antiplatelet agents and outline the potential role of newly developed (novel) antithrombotic agents for pregnant and postpartum patients.

Personalizing Direct Oral Anticoagulant Therapy for a Diverse Population: Role of Race, Kidney Function, Drug Interactions, and Pharmacogenetics

Oral anticoagulants (OACs) are commonly used to reduce the risk of venous thromboembolism and the risk of stroke in patients with atrial fibrillation. Endorsed by the American Heart Association, American College of Cardiology, and the European Society of Cardiology, direct oral anticoagulants (DOACs) have displaced warfarin as the OAC of choice for both conditions, due to improved safety profiles, fewer drug-drug and drug-diet interactions, and lack of monitoring requirements. Despite their widespread use and improved safety over warfarin, DOAC-related bleeding remains a major concern for patients. DOACs have stable pharmacokinetics and pharmacodynamics; however, variability in DOAC response is common and may be attributed to numerous factors, including patient-specific factors, concomitant medications, comorbid conditions, and genetics. Although DOAC randomized controlled trials included patients of varying ages and levels of kidney function, they failed to include patients of diverse ancestries. Additionally, current evidence to support DOAC pharmacogenetic associations have primarily been derived from European and Asian individuals. Given differences in genotype frequencies and disease burden among patients of different biogeographic groups, future research must engage diverse populations to assess and quantify the impact of predictors on DOAC response. Current under-representation of patients from diverse racial groups does not allow for proper generalization of the influence of clinical and genetic factors in relation to DOAC variability. Herein, we discuss factors affecting DOAC response, such as age, sex, weight, kidney function, drug interactions, and pharmacogenetics, while offering a new perspective on the need for further research including frequently excluded groups.

The European guideline on management of major bleeding and coagulopathy following trauma: sixth edition

BACKGROUND

Severe trauma represents a major global public health burden and the management of post-traumatic bleeding continues to challenge healthcare systems around the world. Post-traumatic bleeding and associated traumatic coagulopathy remain leading causes of potentially preventable multiorgan failure and death if not diagnosed and managed in an appropriate and timely manner. This sixth edition of the European guideline on the management of major bleeding and coagulopathy following traumatic injury aims to advise clinicians who care for the bleeding trauma patient during the initial diagnostic and therapeutic phases of patient management.

METHODS

The pan-European, multidisciplinary Task Force for Advanced Bleeding Care in Trauma included representatives from six European professional societies and convened to assess and update the previous version of this guideline using a structured, evidence-based consensus approach. Structured literature searches covered the period since the last edition of the guideline, but considered evidence cited previously. The format of this edition has been adjusted to reflect the trend towards concise guideline documents that cite only the highest-quality studies and most relevant literature rather than attempting to provide a comprehensive literature review to accompany each recommendation.

RESULTS

This guideline comprises 39 clinical practice recommendations that follow an approximate temporal path for management of the bleeding trauma patient, with recommendations grouped behind key decision points. While approximately one-third of patients who have experienced severe trauma arrive in hospital in a coagulopathic state, a systematic diagnostic and therapeutic approach has been shown to reduce the number of preventable deaths attributable to traumatic injury.

CONCLUSION

A multidisciplinary approach and adherence to evidence-based guidelines are pillars of best practice in the management of severely injured trauma patients. Further improvement in outcomes will be achieved by optimising and standardising trauma care in line with the available evidence across Europe and beyond.

Antibody engineering and its therapeutic applications

As a natural function, antibodies defend the host from infected cells and pathogens by recognizing their pathogenic determinants. Antibodies (Abs) gained wide acceptance with an enormous impact on human health and have predominantly captured the arena of bio-therapeutics and bio-diagnostics. The scope of Ab-based biologics is vast, and it is likely to solve many unmet clinical needs in future. The majority of attention is now devoted to developing innovative technologies for manufacturing and engineering Abs, better suited to satisfy human needs. The advent of Ab engineering technologies (AET) led to phenomenal developments leading to the generation of Abs-/Ab-derived molecules with desirable functional properties proportional to their expanding requirements. Evolution brought by AET, from the naturally occurring Ab forms to several advanced Ab formats and derivatives, was much needed as it is of great interest to the pharmaceutical industry. Thus, numerous advancements in AET have propelled success in therapeutic Ab development, along with the potential for ever-increasing improvements. Unique characteristics of Abs, such as its diversity, specificity, structural integrity and an array of possible applications, together inspire continuous innovation in the field. Overall, the AET could assist in conquer of several limitations of Abs in terms of their applicability in the field of therapeutics, diagnostics and research; AET has so far led to the production of next-generation Abs, which have revolutionized these arenas. Here in this review, we discuss the various distinguished engineering platforms for Ab development and the progress in modern therapeutics by the so-called "next-generation Abs."

Aneurysmal Subarachnoid Hemorrhage in Hospitalized Patients on Anticoagulants-A Two Center Matched Case-Control Study

Objective-Direct oral anticoagulants (DOAC) are replacing vitamin K antagonists (VKA) for the prevention of ischemic stroke and venous thromboembolism. We set out to assess the effect of prior treatment with DOAC and VKA in patients with aneurysmal subarachnoid hemorrhage (SAH). Methods-Consecutive SAH patients treated at two (Aachen, Germany and Helsinki, Finland) university hospitals were considered for inclusion. To assess the association between anticoagulant treatments on SAH severity measure by modified Fisher grading (mFisher) and outcome as measured by the Glasgow outcome scale (GOS, 6 months), DOAC- and VKA-treated patients were compared against age- and sex-matched SAH controls without anticoagulants. Results-During the inclusion timeframes, 964 SAH patients were treated in both centers. At the time point of aneurysm rupture, nine patients (0.93%) were on DOAC treatment, and 15 (1.6%) patients were on VKA. These were matched to 34 and 55 SAH age- and sex-matched controls, re-spectively. Overall, 55.6% of DOAC-treated patients suffered poor-grade (WFNS_4-5) SAH compared to 38.2% among their respective controls (p = 0.35); 53.3% of patients on VKA suffered poor-grade SAH compared to 36.4% in their respective controls (p = 0.23). Neither treatment with DOAC (aOR 2.70, 95%CI 0.30 to 24.23; p = 0.38), nor VKA (aOR 2.78, 95%CI 0.63 to 12.23; p = 0.18) were inde-pendently associated with unfavorable outcome (GOS_1-3) after 12 months. Conclusions-Iatrogenic coagulopathy caused by DOAC or VKA was not associated with more severe radiological or clinical subarachnoid hemorrhage or worse clinical outcome in hospitalized SAH patients.

The role of anticoagulation clinics needs to be reassessed to include follow up of patients on direct oral anticoagulants

A survey was carried out to assess the state of organization of care (including clinical and laboratory) delivered to patients on vitamin K antagonists (VKA) or direct oral anticoagulants (DOAC) followed by clinics affiliated with the Italian Federation of Thrombosis Centers (FCSA), traditionally engaged to assist anticoagulated outpatients within the country. Participants were asked to answer questions concerning (i) proportion of patients on VKA-vs-DOAC and (ii) whether dedicated testing for DOAC is available. The proportion of patients on VKA-vs-DOAC was 60 % vs 40 %. This proportion is in sharp contrast with the real-life distribution where DOAC outweigh VKA prescriptions. Furthermore, the proportion of anticoagulation clinics that provide DOAC testing (even in special situations) is relatively small (i.e., 31 % of the respondents). Furthermore, 25 % of those that declared to follow DOAC patients do not provide any testing at all. The answers to the above questions cause concerns as (i) most patients on DOAC within the country are probably on self-management, or they are managed by general practitioners or specialists outside thrombosis centers. (ii) Most patients on DOAC have no access to testing even in special situations where it would be needed. We feel that there is a (false) perception that the care needed for DOAC treatment can be much less than that required for VKA, as DOAC require prescription and not regular follow-up. A call for action should be urgently made to reassess the role of anticoagulation clinics, which should pay the same attention to patients on DOAC as those on VKA.

Mechanisms of ADC Toxicity and Strategies to Increase ADC Tolerability

Anti-cancer antibody-drug conjugates (ADCs) aim to expand the therapeutic index of traditional chemotherapy by employing the targeting specificity of monoclonal antibodies (mAbs) to increase the efficiency of the delivery of potent cytotoxic agents to malignant cells. In the past three years, the number of ADCs approved by the Food and Drug Administration (FDA) has tripled. Although several ADCs have demonstrated sufficient efficacy and safety to warrant FDA approval, the clinical use of all ADCs leads to substantial toxicity in treated patients, and many ADCs have failed during clinical development due to their unacceptable toxicity profiles. Analysis of the clinical data has demonstrated that dose-limiting toxicities (DLTs) are often shared by different ADCs that deliver the same cytotoxic payload, independent of the antigen that is targeted and/or the type of cancer that is treated. DLTs are commonly associated with cells and tissues that do not express the targeted antigen (i.e., off-target toxicity), and often limit ADC dosage to levels below those required for optimal anti-cancer effects. In this manuscript, we review the fundamental mechanisms contributing to ADC toxicity, we summarize common ADC treatment-related adverse events, and we discuss several approaches to mitigating ADC toxicity.

Discovery of novel N-acylpyrazoles as potent and selective thrombin inhibitors

Direct oral anticoagulants (DOACs), which includes thrombin and factor Xa inhibitors, have emerged as the preferred therapeutics for thrombotic disorders, penetrating a market previously dominated by warfarin and heparin. This article describes the discovery and profiling of a novel series of N-acylpyrazoles, which act as selective, covalent, reversible, non-competitive inhibitors of thrombin. We describe in vitro stability issues associated with this chemotype and, importantly, demonstrate that N-acylpyrazoles successfully act in vivo as anticoagulants in basic thrombotic animal models. Crucially, this anticoagulant nature is unaccompanied by the higher bleeding risk profile that has become an undesirable characteristic of the DTIs and factor Xa inhibitors. We propose that the N-acylpyrazole chemotype shows intriguing promise as next-generation oral anticoagulants.

Fibrinogen, Coagulation, and Ageing

The World Health Organization estimates that the world's population over 60 years of age will nearly double in the next 30 years. This change imposes increasing demands on health and social services with increased disease burden in older people, hereafter defined as people aged 60 years or more. An older population will have a greater incidence of cardiovascular disease partly due to higher levels of blood fibrinogen, increased levels of some coagulation factors, and increased platelet activity. These factors lead to a hypercoagulable state which can alter haemostasis, causing an imbalance in appropriate coagulation, which plays a crucial role in the development of cardiovascular diseases. These changes in haemostasis are not only affected by age but also by gender and the effects of hormones, or lack thereof in menopause for older females, ethnicity, other comorbidities, medication interactions, and overall health as we age. Another confounding factor is how we measure fibrinogen and coagulation through laboratory and point-of-care testing and how our decision-making on disease and treatment (including anticoagulation) is managed. It is known throughout life that in normal healthy individuals the levels of fibrinogen and coagulation factors change, however, reference intervals to guide diagnosis and management are based on only two life stages, paediatric, and adult ranges. There are no specific diagnostic guidelines based on reference intervals for an older population. How ageing relates to alterations in haemostasis and the impact of the disease will be discussed in this chapter. Along with the effect of anticoagulation, laboratory testing of fibrinogen and coagulation, future directions, and implications will be presented.

Coagulopathy in Isolated Traumatic Brain Injury: Myth or Reality

INTRODUCTION

Traumatic Brain Injury (TBI) has been shown to be associated with altered hemostasis and coagulopathy, that correlates with worsening secondary injury and clinical outcomes. Isolated Traumatic Brain Injury (iTBI), that is TBI without significant extracranial injuries, has also been shown to be associated with systemic coagulopathy and derangements in hemostasis.

METHODS

Literature Review.

RESULTS

Present your results in logical sequence in the text, tables, and figures, giving the main or most important findings first. Do not repeat all the data in the tables or figures in the text; emphasize or summarize only the most important observations. Provide data on all primary and secondary outcomes identified in the Methods section. Give numeric results not only as derivatives (e.g. percentages) but also as the absolute numbers from which the derivatives were calculated, and specify the statistical significance attached to them, if any.

DISCUSSION

In this review, we provide an overview of the pathophysiology of the hemostatic disturbances caused by iTBI, review key clinical findings and discrepancies in the way this question has been approached, describe the use and role of global viscoelastic assays such as the thromboelastrogram, and detail principles for reversal of pre-injury blood thinners.

CONCLUSIONS

iTBI is clearly associated with the development of coagulopathy, but the extent to which it occurs is confounded by the fact that many of the studies have included patients with moderate extracranial trauma into the iTBI category. The coagulopathy itself has been better studied in preclinical models, and the mechanisms driving it suggest a pattern consistent with disseminated intravascular coagulation with hyperfibrinolysis. We provide pragmatic clinical takeaways and suggestions for future research.