American Society of Hematology 2018 guidelines for management of venous thromboembolism: optimal management of anticoagulation therapy

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.

Anticoagulation and compression therapy for proximal acute deep vein thrombosis

The treatment of proximal deep vein thrombosis (DVT) of the lower limbs includes an initial management phase, covering the first 1 to 3 weeks, a primary treatment phase, lasting a minimum of 3 months, and a secondary treatment phase for those patients requiring continuing anticoagulation beyond the first 3 to 6 months. During the initial phase most patients with DVT can be managed as outpatients. Exclusion criteria for home treatment include high risk of bleeding, limb threatening DVT or other conditions requiring hospitalisation. Anticoagulant drugs represent the mainstay of treatment and include parenteral drugs such as unfractionated heparin or low molecular weight heparin, and oral drugs such as the vitamin K antagonists and the direct oral anticoagulants (DOACs). DOACs are currently recommended as the first line of treatment for proximal DVT of the lower limbs, with no preference for one DOAC over another. Factors to consider when choosing the anticoagulant strategy include, among others, renal and liver function, underlying diseases such as cancer or the antiphospholipid syndrome, and patient preferences. Indefinite duration of anticoagulation beyond the first 3 to 6 months is recommended for patients with unprovoked DVT and patients with permanent, chronic risk factors. Two DOACs, namely apixaban and rivaroxaban, can be administered at low doses for the secondary prevention of DVT. Elastic compression stockings (ECS) have been used for decades in patients with proximal DVT with the aim of counteracting the venous hypertension generated by the vascular disorder and reducing leg edema and to prevent the post-thrombotic syndrome.

Poor patients' knowledge about venous thromboembolism and its therapy is associated with increased risk of major bleeding and discontinuation of anticoagulation: A cohort study

It has been shown that patients' knowledge about venous thromboembolism (VTE) and its therapy is suboptimal, which might reduce compliance and worsen prognosis. We investigated whether low VTE patients' knowledge affects their clinical outcomes during long-term follow-up. We evaluated 151 consecutive patients (51.8 ± 15.7 years) after unprovoked VTE, who were recruited from the outpatient clinic (Krakow, Poland). All patients received anticoagulant treatment, mostly with direct oral anticoagulants (n = 113, 74.8%). The modified Jessa Atrial fibrillation Knowledge Questionnaire (JAKQ-VTE; 16 questions) was used to assess the knowledge of VTE and anticoagulant therapy. During a median follow-up of 58.0 months, VTE recurrence, major bleeding, and anticoagulation withdrawal were recorded. The median percentage of correct responses was 62.5% (12.5-100%) and was inversely correlated with age (P < .01). Diabetic patients and those with positive family history of VTE had lower overall scoring compared to the remainder (both P < .05). Major bleeding (n = 10, 6.6%) and anticoagulation withdrawal (n = 28, 18.5%), but not VTE recurrence (n = 12, 7.9%), were associated with lower overall scoring compared to the remainder (48.8% ± 12.5% vs 63.8% ± 16.3%, P = .003 and 55.3% ± 14.7% vs 64.4% ± 16.3%, P = .040, respectively). Major bleeding was independently associated with the female sex (hazard ratio [HR] 6.18; 95% confidence interval [CI] 1.15-33.19, P = .034), younger age (HR per 10 years 0.55; 95% CI 0.34-0.90, P = .016), OAC therapy discontinuation (HR 6.69; 95% CI 1.62-27.70), and lower overall scoring of JAKQ-VTE (HR 0.60 per 10 percentage points; 95% CI 0.40-0.92, P = .019). Insufficient knowledge about VTE and anticoagulant treatment predisposes to a higher risk of major bleeding and therapy discontinuation, but not VTE recurrence in unprovoked VTE patients during long-term follow-up.

Incidence, Predictors, and Outcomes of Venous and Arterial Thrombosis in COVID-19: A Nationwide Inpatient Analysis

BACKGROUND

Coronavirus disease 2019 (COVID-19) is known to increase the risk of venous thromboembolism (VTE) and arterial thromboembolism (ATE). However, the incidence, predictors, and outcomes of clinical thrombosis for inpatients with COVID-19 are not well known. This study aimed to enhance our understanding of clinical thrombosis in COVID-19, its associated factors, and mortality outcomes.

METHOD

Hospitalised adult (≥18 years of age) patients with COVID-19 in 2020 were retrospectively identified from the US National Inpatient Sample database. Clinical characteristics, incident VTE, ATE, and in-hospital mortality outcomes were recorded. Multivariable logistic regression was performed to identify clinical factors associated with thrombosis and in-hospital mortality in COVID-19 inpatients.

RESULTS

A total of 1,583,135 adult patients with COVID-19 in the year 2020 were identified from the National Inpatient Sample database; patients with thrombosis were 41% females with a mean age of 65.4 (65.1-65.6) years. The incidence of thrombosis was 6.1% (97,185), including VTE at 4.8% (76,125), ATE at 3.0% (47,790), and the in-hospital mortality rate was 13.4% (212,785). Patients with thrombosis were more likely to have respiratory symptoms of COVID-19 (76.7% vs 75%, p<0.001) compared with patients without thrombosis. The main factors associated with overall thrombosis, VTE, and ATE were paralysis, ventilation, solid tumours without metastasis, metastatic cancer, and acute liver failure. Although all thrombosis categories were associated with higher in-hospital mortality for COVID-19 inpatients in univariable analyses (p<0.001), they were not in multivariable analyses-thrombosis (odds ratio [OR] 1.24; 95% confidence interval [CI] 0.90-1.70; p=0.19), VTE (OR 0.70; 95% CI 0.52-1.00; p=0.05), and ATE (OR 1.07; 95% CI 0.92-1.25; p=0.36).

CONCLUSIONS

The association of COVID-19 with thrombosis and VTE increases with increasing severity of the COVID-19 disease. Risk stratification of thrombosis is crucial in COVID-19 patients to determine the necessity of thromboprophylaxis.

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.

Comparison of anticoagulation control and outcomes between usual medical care and pharmacist-led anticoagulation service in ambulatory patients taking warfarin at tertiary hospital in Ethiopia: a quasi-experimental study

BACKGROUND

We aimed to compare anticoagulation control and outcomes between usual medical care (UMC) and pharmacist-led anticoagulation services (PLAS) in patients receiving warfarin at the Tikur Anbessa Specialized Hospital (TASH), Addis Ababa, Ethiopia.

METHODS

A quasi-experimental study was conducted, including 350 (66.7%) and 175 (33.3%) patients from the UMC and PLAS groups, respectively, from 525 patients. The time in therapeutic range (TTR) was determined using the Rosendaal method, with a TTR ≥ 65% set as the cut-off for optimal anticoagulation. The two-sample Wilcoxon rank-sum (Mann-Whitney U) test was used to compare continuous variables between groups. Categorical variables were compared between groups using Pearson's chi-square test or Fisher's exact test. Logistic regression and negative binomial regression analyses were conducted to identify the factors associated with suboptimal TTR and secondary outcomes, respectively, at the p values < 0.05, and 95% confidence interval (CI).

RESULTS

Compared with the UMC group, the patients in the PLAC group showed a significantly higher median (IQR) TTR [60.89% (43.5-74.69%) vs. 53.65% (33.92-69.14%), p < 0.001]. A significantly higher optimal TTR (≥ 65%) was achieved in the PLAC group (41.7% vs. 31.7%) than in the UMC group (p = 0.002). The odds of having a poor TTR were reduced by 43% (AOR = 0.57, 95% CI = 0.36-0.88, p = 0.01) among patients in the PLAC group compared to those in the UMC group. There were no statistically significant differences in the secondary outcomes between the groups, except for all-cause emergency visits (p = 0.003). The incidence of bleeding events decreased by 3% (IRR = 0.97, 95% CI = 0.96-0.99, p < 0.001) for every increase in INR monitoring frequency. The incidence of thromboembolic events increased by a factor of 15.13 (IRR = 15.13, 95% CI = 1.47-155.52, p = 0.02) among patients with a high-risk CHA2DS2-VASc score compared with those with a moderate score.

CONCLUSION

Patients in the PLAC group had a significantly higher median TTR than those in the UMC group did. There were no statistically significant differences in the secondary outcomes between the groups, except for fewer all-cause emergency department visits in the PLAC group.

Hemostasis Testing in the Emergency Department: A Narrative Review

Routine laboratory screening is typically performed at initial evaluation of the vast majority of presentations to the emergency department (ED). These laboratory results are crucial to the diagnostic process, as they may influence up to 70% of clinical decisions. However, despite the usefulness of biological assessments, many tests performed are inappropriate or of doubtful clinical relevance. This overutilization rate of laboratory testing in hospitals, which represents a significant medical-economic burden, ranges from 20 to 67%, with coagulation tests at the top of the list. While reviews frequently focus on nonintensive care units, there are few published assessments of emergency-specific interventions or guidelines/guidance to date. The aim of this review is to highlight current recommendations for hemostasis evaluation in the emergency setting with a specific analysis of common situations leading to ED admissions, such as suspected venous thrombosis or severe bleeding. We revisit the evidence related to the assessment of patient's hemostatic capacity based on comprehensive history taking and physical examination as well as best practice recommendations for blood sample collection to ensure the reliability of results. This review also includes an examination of various currently available point of care tests and a comprehensive discussion on indications, limitations, and interpretation of these tests.

DOAC-Remove to counteract the interference of anti-Xa oral anticoagulants on the monitoring of heparin

INTRODUCTION

The monitoring of unfractionated heparin (UFH) by anti-factor Xa activity (AXA) is commonly used to ensure effective anticoagulation and prevent bleeding risk. However, in patients previously treated with an anti-Xa direct oral anticoagulant (DOAC) switching to UFH therapy, there is a risk of interference that may lead to inappropriate anticoagulation. The first objective of this study was to validate DOAC-Remove to remove DOAC for measuring UFH specific AXA. The second objective was to assess the length of DOAC interference on UFH monitoring and to identify potential predictive factors.

MATERIALS AND METHODS

This monocentric retrospective study included all patients admitted from April 2019 to April 2021 previously treated with anti-Xa DOAC, and for whom an interference on UFH monitoring was suspected. Interference was defined as a difference in the AXA measured before and after using DOAC-Remove >2.8-fold standard deviation of the method.

RESULTS

Removal with DOAC-Remove was specific of DOAC (apixaban n = 42, rivaroxaban n = 41, UFH n = 20) and sufficient to avoid interference on UFH AXA measurement. The exact interference length was 6.0 days [IQR 3.0-11.0] for apixaban (n = 26) and 4.5 days [IQR 2.0-5.8] for rivaroxaban (n = 20). Among the 89 patients sorted based on an interference length ≤ or >3 days, 74 (83.1%) presented an interference greater than 3 days. Correlations were observed with age for apixaban and creatinine for rivaroxaban.

CONCLUSIONS

Our results suggest that DOAC-Remove could be of high interest in patients receiving UFH previously treated with an anti-Xa DOAC even if DOAC was stopped for more than 3 days.

Andexanet Alfa versus Four-Factor Prothrombin Complex Concentrate for the Reversal of Factor Xa (FXa) Inhibitor-Associated Intracranial Hemorrhage: A Systematic Review of Retrospective Studies

Background/Objectives: There are limited data on the risks and benefits of using Andexanet alfa (AA) compared with four-factor prothrombin complex concentrate (4F-PCC) for the reversal of factor Xa inhibitor-associated intracranial hemorrhage (ICH). Our aim was to describe a compilation of the information available in the literature to date. Methods: PubMed, Embase, Web of Science (Clarivate Analytics) and the Cochrane Central Register of Controlled Trials were searched until December 2023. Following the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)" guidelines, our systematic literature review included studies that were retrospective in design and evaluated both drugs to control bleeding and complications (death and thromboembolic events). Two researchers re-examined the studies for relevance, extracted the data and assessed the risk of bias. No meta-analyses were performed for the results. Results: In this limited patient sample, we found no differences between published articles in terms of neuroimaging stability or thrombotic events. However, some studies show significant differences in mortality, suggesting that one of the AAs may be superior to 4F-PCC. Conclusions: Our qualitative analysis shows that AA has a better efficacy profile compared with 4F-PCC. However, further studies monitoring these patients and a multicenter collaborative network dedicated to this topic are needed.

Idarucizumab in dabigatran-treated patients with acute stroke: a review and clinical update

Idarucizumab is an antibody fragment specific for the immediate reversal of dabigatran anticoagulation effects. The use of idarucizumab is approved for dabigatran-treated patients suffering from life-threatening or uncontrolled bleeding and those in need of urgent surgery or invasive procedures. Data from randomized controlled clinical trials and real-world experience provide reassuring evidence about the efficacy and safety of idarucizmab use in patients with acute stroke. In this narrative review, we summarize the available real-world evidence and discuss the relevance and importance of idarucizumab treatment in acute stroke patients in everyday clinical practice. In addition, we also discuss special issues like prothrombin complex concentrate application as an alternative to idarucizumab, its application before endovascular therapy, sensitivity of thrombi to lysis, and necessary laboratory examinations.

Coordination of oral anticoagulant care at hospital discharge (COACHeD): pilot randomised controlled trial

OBJECTIVES

To evaluate whether a focused, expert medication management intervention is feasible and potentially effective in preventing anticoagulation-related adverse events for patients transitioning from hospital to home.

DESIGN

Randomised, parallel design.

SETTING

Medical wards at six hospital sites in southern Ontario, Canada.

PARTICIPANTS

Adults 18 years of age or older being discharged to home on an oral anticoagulant (OAC) to be taken for at least 4 weeks.

INTERVENTIONS

Clinical pharmacologist-led intervention, including a detailed discharge medication management plan, a circle of care handover and early postdischarge virtual check-up visits to 1 month with 3-month follow-up. The control group received the usual care.

OUTCOMES MEASURES

Primary outcomes were study feasibility outcomes (recruitment, retention and cost per patient). Secondary outcomes included adverse anticoagulant safety events composite, quality of transitional care, quality of life, anticoagulant knowledge, satisfaction with care, problems with medications and health resource utilisation.

RESULTS

Extensive periods of restriction of recruitment plus difficulties accessing patients at the time of discharge negatively impacted feasibility, especially cost per patient recruited. Of 845 patients screened, 167 were eligible and 56 were randomised. The mean age (±SD) was 71.2±12.5 years, 42.9% females, with two lost to follow-up. Intervention patients were more likely to rate their ability to manage their OAC as improved (17/27 (63.0%) vs 7/22 (31.8%), OR 3.6 (95% CI 1.1 to 12.0)) and their continuity of care as improved (21/27 (77.8%) vs 2/22 (9.1%), OR 35.0 (95% CI 6.3 to 194.2)). Fewer intervention patients were taking one or more inappropriate medications (7 (22.5%) vs 15 (60%), OR 0.19 (95% CI 0.06 to 0.62)).

CONCLUSION

This pilot randomised controlled trial suggests that a transitional care intervention at hospital discharge for older adults taking OACs was well received and potentially effective for some surrogate outcomes, but overly costly to proceed to a definitive large trial.

TRIAL REGISTRATION NUMBER

NCT02777047.

Outcomes of Warfarin Home INR Monitoring vs Office-Based Monitoring: a Retrospective Claims-Based Analysis

BACKGROUND

Home INR testing (patient self-testing) is feasible and effective for warfarin patients but little is known about real-world differences in outcomes for patients using PST versus laboratory-based INR monitoring.

OBJECTIVE

To compare the safety/efficacy of patient self-testing of real-world warfarin therapy versus office/lab-based monitoring of therapy.

DESIGN/SETTING/PARTICIPANTS/EXPOSURE

A retrospective claims-based analysis of warfarin patients enrolled in the MarketScan® Commercial Claims and Encounters and Medicare databases between January 1, 2013, and March 30, 2020. Stratification was based on INR testing method: patient self-testing versus testing at physicians' offices/local laboratory. The probability of adverse events in each cohort was determined after adjusting for demographic and baseline clinical characteristics using a repeated measures analysis.

MAIN MEASURES

Rates of all adverse events: deep venous thrombosis, pulmonary embolism, bleeding, and stroke. A secondary outcome of interest was emergency department visits.

KEY RESULTS

A total of 37,837 patients were included in the analysis: 1592 patients in the patient self-testing group and 36,245 in the office-based therapy group. After adjusting for demographic and baseline clinical characteristics, patients in the office-based group had statistically significantly higher rates of all adverse events (incidence rate ratio [IRR]=2.07, 95% CI [1.82, 2.36]), and specific adverse events including thromboembolism (IRR=4.38, 95% CI [3.29, 5.84]), major bleed (IRR=1.45, 95% CI [1.28, 1.64]), and stroke (IRR=1.30, 95% CI [1.05, 1.61]) than patients in the patient self-testing group. Office-based patients also had a statistically significant higher rate of emergency department visits than patient self-testing patients (IRR = 1.65, 95% CI [1.47, 1.84]).

CONCLUSIONS/RELEVANCE

This analysis of real-world claims data shows lower rates of stroke, thromboembolism, and major bleeding, as well as fewer emergency department visits, with patient self-testing compared to office-based/lab INR monitoring. Our finding that PST is safe and effective among current users suggests that more patients may benefit from its use.

Transition of management strategies and long-term outcomes in cancer-associated venous thromboembolism from the warfarin era to the direct oral anticoagulant era

BACKGROUND

There have been still limited data on the transition of management strategies and clinical outcomes after introduction of direct oral anticoagulant (DOAC) for cancer-associated venous thromboembolism (VTE) in the real-world clinical practice.

METHODS

Using the 2 series of multicenter COMMAND VTE registries in Japan enrolling consecutive patients with acute symptomatic VTE, we compared 695 patients with cancer-associated VTE in the Registry-1 of the warfarin era and 1507 patients in the Registry-2 of the DOAC era.

RESULTS

Regarding oral anticoagulation therapy, 576 patients (82.9 %) in the Registry-1 received warfarin, whereas 1119 patients (79.6 %) in the Registry-2 received DOACs. The cumulative 3-year incidence of discontinuation of anticoagulation was not significantly different between the 2 registries (56.7 % vs. 62.7 %, P = 0.11). The cumulative 5-year incidence of recurrent VTE was significantly lower in the Registry-2 than in the Registry-1 (17.7 % vs. 10.1 %, P < 0.001). The cumulative 5-year incidence of major bleeding was significantly lower in the Registry-2 than in the Registry-1 (26.6 % vs. 20.4 %, P = 0.045). The proportion of gastrointestinal bleeding numerically increased from the Registry-1 to the Registry-2 (46.7 % and 49.5 %), whereas that of intracranial bleeding numerically decreased from the Registry-1 to the Registry-2 (17.1 % and 14.1 %).

CONCLUSIONS

In the current historical comparison of cancer-associated VTE between the 2 large real-world registries, there was a striking change in the treatment strategies with decreased risks of recurrent VTE and major bleeding in the DOAC era compared with those in the warfarin era, while there seemed to be unmet needs of DOAC-related gastrointestinal bleeding.

CLINICAL TRIAL REGISTRATION

URL: http://www.umin.ac.jp/ctr/index.htm UNIQUE IDENTIFIER: UMIN000044816.

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.

Effect of rt-PA on Shear Wave Mechanical Assessment and Quantitative Ultrasound Properties of Blood Clot Kinetics In Vitro

OBJECTIVE

The consequences associated with blood clots are numerous and are responsible for many deaths worldwide. The assessment of treatment efficacy is necessary for patient follow-up and to detect treatment-resistant patients. The aim of this study was to characterize the effect of treatment on blood clots in vitro using quantitative ultrasound parameters.

METHODS

Blood from 10 pigs was collected to form three clots per pig in gelatin phantoms. Clots were subjected to 1) no treatment, 2) rt-PA (recombinant tissue plasminogen activator) treatment after 20 minutes of clotting, and 3) rt-PA treatment after 60 minutes of clotting. Clots were weighted before and after the experiment to assess the treatment effect by the mass loss. The clot kinetics was studied over 100 minutes using elastography (Young's modulus, shear wave dispersion, and shear wave attenuation). Homodyne K-distribution (HKD) parameters derived from speckle statistics were also studied during clot formation and dissolving (diffuse-to-total signal power ratio and intensity parameters).

RESULTS

Treated clots loosed significantly more mass than non-treated ones (P < .005). A significant increase in Young's modulus was observed over time (P < .001), and significant reductions were seen for treated clots at 20 or 60 minutes compared with untreated ones (P < .001). The shear wave dispersion differed for treated clots at 60 minutes versus no treatments (P < .001). The shear wave attenuation decreased over time (P < .001), and was different for clots treated at 20 minutes versus no treatments (P < .031). The HKD intensity parameter varied over time (P < .032), and was lower for clots treated at 20 and 60 minutes than those untreated (P < .001 and P < .02).

CONCLUSION

The effect of rt-PA treatment could be confirmed by a decrease in Young's modulus and HKD intensity parameter. The shear wave dispersion and shear wave attenuation were sensitive to late and early treatments, respectively. The Young's modulus, shear wave attenuation, and HKD intensity parameter varied over time despite treatment.

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.

Timing Matters: A Machine Learning Method for the Prioritization of Drug-Drug Interactions Through Signal Detection in the FDA Adverse Event Reporting System and Their Relationship with Time of Co-exposure

INTRODUCTION

Current drug-drug interaction (DDI) detection methods often miss the aspect of temporal plausibility, leading to false-positive disproportionality signals in spontaneous reporting system (SRS) databases.

OBJECTIVE

This study aims to develop a method for detecting and prioritizing temporally plausible disproportionality signals of DDIs in SRS databases by incorporating co-exposure time in disproportionality analysis.

METHODS

The method was tested in the Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS). The CRESCENDDI dataset of positive controls served as the primary source of true-positive DDIs. Disproportionality analysis was performed considering the time of co-exposure. Temporal plausibility was assessed using the flex point of cumulative reporting of disproportionality signals. Potential confounders were identified using a machine learning method (i.e. Lasso regression).

RESULTS

Disproportionality analysis was conducted on 122 triplets with more than three cases, resulting in the prioritization of 61 disproportionality signals (50.0%) involving 13 adverse events, with 61.5% of these included in the European Medicine Agency's (EMA's) Important Medical Event (IME) list. A total of 27 signals (44.3%) had at least ten cases reporting the triplet of interest, and most of them (n = 19; 70.4%) were temporally plausible. The retrieved confounders were mainly other concomitant drugs.

CONCLUSIONS

Our method was able to prioritize disproportionality signals with temporal plausibility. This finding suggests a potential for our method in pinpointing signals that are more likely to be furtherly validated.

Smaller nadroparin dose reductions required for patients with renal impairment: A multicenter cohort study

BACKGROUND

Guidelines advise 50 % and 25 % dose reduction of the therapeutic nadroparin dose (86 IU/kg) in patients with eGFR 15-29 and 30-60 ml/min respectively. For monitoring, peak anti-Xa levels are suggested. Data lack whether this results in therapeutic anti-Xa levels or in anti-Xa levels that are comparable to those of patients without renal impairment.

AIMS

To determine dose ranges in patients with renal impairment that result in therapeutic anti-Xa levels and to determine the percentage of the 86 IU/kg dose that results in anti-Xa levels normally occurring in patients without renal impairment.

METHODS

A retrospective cohort study was conducted in five hospitals. Patients ≥18 years of age, with an eGFR ≥ 15 ml/min were included. The first correctly sampled peak (i.e. 3-5 h after ≥ third administration, regardless of dose per patient) was included. Simulated prediction models were developed using multiple linear regression.

RESULTS

770 patients were included. eGFR and hospital affected the association between dose and anti-Xa level. The doses for peak anti-Xa levels of 0.75 IU/ml differed substantially between hospitals and ranged from 55 to 91, 65-359 and 68-168 IU/kg in eGFR 15-29, 30-60 and > 60 ml/min/1.73m2, respectively. In eGFR 15-29 and 30-60 ml/min/1.73m2, doses of 75 % and 91 % of 86 IU/kg respectively, were needed for anti-Xa levels normally occurring in patients with eGFR > 60 ml/min.

CONCLUSION

We advise against anti-Xa based dose-adjustments as long as anti-Xa assays between laboratories are not harmonized and an anti-Xa target range is not validated. A better approach might be to target levels similar to eGFR > 60 ml/min/1.73m2, which are achieved by smaller dose reductions.

Risk Stratification for Supratherapeutic Peak Anti-Xa Levels in Adult Patients on Therapeutic Enoxaparin

BACKGROUND

The American Society of Hematology Guidelines for the management of venous thromboembolism recommend against the use of anti-Xa monitoring for assessing enoxaparin dosing based on a low level of evidence associating supratherapeutic levels with an increased risk of bleeding. However, institutions still utilize anti-Xa levels in select patient populations with altered volume of distribution and/or excretion to monitor and adjust therapy.

OBJECTIVE

The primary objective of this study was to identify risk factors associated with supratherapeutic peak anti-Xa levels (≥1.10 IU/mL) for patients receiving therapeutic enoxaparin.

METHODS

This was a retrospective single-center study performed at an academic tertiary care hospital. Patients who received enoxaparin at 1 mg/kg twice daily and peak anti-Xa monitoring were separated into supratherapeutic and therapeutic/subtherapeutic cohorts.

RESULTS

A total of 436 patients were screened, and 215 were included, with a mean age of 62 years. There were 108 in the therapeutic/subtherapeutic cohort and 107 in the supratherapeutic cohort. Acute kidney injury (AKI), body mass index (BMI), weight, female sex, intensive care unit (ICU) service, Sequential Organ Failure Assessment (SOFA) score ≥4, and creatinine clearance at the time of peak anti-Xa level collection were associated with supratherapeutic anti-Xa levels in univariate models. Adjusted logistic regression models were created and identified BMI in the 30 to 34.9 kg/m2 (odds ratio [OR] 4.35; 95% confidence interval [CI] 1.70-11.13, P < 0.005) and ≥35 kg/m2 (OR 6.75; 95% CI 3.05-14.94, P < 0.005) and AKI (OR 2.62; 95% CI 1.04-6.62, P = 0.042) as significant risk factors for supratherapeutic anti-Xa levels.

CONCLUSION AND RELEVANCE

Our study identified BMI ≥ 30 kg/m2, AKI, female sex, ICU service, SOFA score ≥4, and creatinine clearance as risk factors for supratherapeutic anti-Xa levels in patients receiving 1 mg/kg twice daily dosing of enoxaparin. Further research should be done to provide evidence for the association between anti-Xa levels and bleeding risk.

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.

Assessment of Temporary Warfarin Reversal in Patients With Left Ventricular Assist Devices: the KVAD Study

BACKGROUND

Patients with left ventricular assist devices (LVADs) require interruption of warfarin for invasive procedures, but parenteral bridging is associated with many complications. Four-factor prothrombin complex concentrate (4F-PCC) can temporarily restore hemostasis in patients undergoing anticoagulation with warfarin.

OBJECTIVES

This pilot study evaluated the strategy of using variable-dose 4F-PCC to immediately and temporarily reverse warfarin before invasive procedures without holding warfarin in patients with LVADs. The duration of effect of 4F-PCC on factor levels and time to reestablish therapeutic anticoagulation post procedure were assessed.

METHODS

Adult patients with LVADs and planned invasive procedures were enrolled from a single center. Warfarin was continued uninterrupted. The 4F-PCC dose administered immediately pre-procedure was based on study protocol. International normalized ratio (INR)- and vitamin K-dependent factor levels were collected before and during the 48 hours after 4F-PCC administration. The use of parenteral bridging, International Society for Thrombosis and Haemostasis major and clinically relevant nonmajor bleeding (CRNMB) and thromboembolic events at 7 and 30 days were collected.

RESULTS

In 21 episodes of 4F-PCC reversal, median baseline INR was 2.7 (IQR 2.2-3.2). The median dosage of 4F-PCC administered was 1794 units (IQR 1536-2130). At 24 and 48 hours post 4F-PCC administration, median INRs were 1.8 (IQR 1.7-2.0) and 2.0 (IQR 1.9-2.4). Two patients required postoperative bridging. One patient experienced major bleeding within 72 hours, and 2 experienced CRNMB within 30 days. There were no thromboembolic events. Baseline and post 4F-PCC vitamin K-dependent factor levels corresponded with changes in INR values. The median time to achieve therapeutic INR post-procedure was 2.5 days (IQR, 1-4).

CONCLUSION

Administration of 4F-PCC for temporary reversal of warfarin for invasive procedures in patients with LVADs allowed for continued warfarin dosing with minimal use of post-intervention bridging, limited bleeding and no thromboembolic events.

Appraising the quality standard of clinical practice guidelines related to central venous catheter-related thrombosis prevention: a systematic review of clinical practice guidelines

OBJECTIVE

To evaluate the quality and analyse the content of clinical practice guidelines regarding central venous catheter-related thrombosis (CRT) to provide evidence for formulating an evidence-based practice protocol and a risk assessment scale to prevent it.

DESIGN

Scoring and analysis of the guidelines using the AGREE II and AGREE REX scales.

DATA SOURCES

Pubmed, Embase, Cochrane Library, Web of Science, CNKI, Wanfang, VIP, and the Chinese Biomedical Literature, and the relevant websites of the guideline, were searched from 1 January 2017 to 26 March 2022.

ELIGIBILITY CRITERIA

Guidelines covering CRT treatment, prevention, or management were included from 1 January 2017 to 26 March 2022.

DATA EXTRACTION AND SYNTHESIS

Three independent reviewers systematically trained in using the AGREE II and AGREE REX scales were selected to evaluate these guidelines.

RESULTS

Nine guidelines were included, and the quality grade results showed that three were at A-level and six were at B-level. The included guidelines mainly recommended the prevention measure of central venous CRT from three aspects: risk screening, prevention strategies, and knowledge training, with a total of 22 suggestions being recommended.

CONCLUSION

The overall quality of the guidelines is high, but there are few preventive measures for central venous CRT involved in the guidelines. All preventive measures have yet to be systematically integrated and evaluated, and no risk assessment scale dedicated to this field has been recommended. Therefore, developing an evidence-based practice protocol and a risk assessment scale to prevent it is urgent.

Venous thromboembolism management in people with cystic fibrosis

BACKGROUND

Rates of venous thromboembolism (VTE) are increasing in people with cystic fibrosis (PwCF). Providers treating VTE in PwCF have reported low confidence concerning anticoagulant drug selection, dose, duration, and drug-drug interactions. As there are currently no published reports regarding management of VTE in PwCF, our objective was to describe the management of VTE in PwCF.

METHODS

PwCF and VTE at the University of Utah Health were identified through electronic medical record searches. Patients were categorized into one of three treatment groups: warfarin, direct oral anticoagulant (DOAC), and low molecular weight heparin (LMWH). The primary outcome was episodes of major bleeding. Secondary outcomes included clinically relevant nonmajor (CRNM) bleeding.

RESULTS

Nine PwCF with a total of 12 unique VTE episodes were included in the study, with all but one episode associated with a peripherally inserted central catheter (PICC). Of the 12 VTE cases, 25% were treated with warfarin, 50% with a DOAC, and 25% with LMWH. There were no episodes of major bleeding and only one episode of CRNM bleeding (Hemoptysis) in the LMWH group. All anticoagulant doses and durations generally followed guidelines for persons without CF. DOACs were the most common VTE treatment, at doses and duration consistent with guidelines for persons without CF, with no major or CRNM bleeding.

CONCLUSION

VTE treatment in PwCF is generally consistent with guidelines for persons without CF with low rates of bleeding. DOACs are a potential option for treatment of VTE in PwCF, but more research is needed.

Clinical outcomes associated with anti-Xa-monitored enoxaparin for venous thromboembolism prophylaxis

STUDY OBJECTIVE

The objective of the study was to assess clinical outcomes (composite of any venous thromboembolism [VTE], any bleeding, and mortality) associated with anti-Xa monitoring in the 30 days following enoxaparin initiation for VTE prophylaxis.

DESIGN

Retrospective cohort study.

SETTING

Hospital within an academic healthcare system.

PATIENTS

Propensity score-matched hospitalized adults receiving enoxaparin for VTE prophylaxis.

INTERVENTION

Low-molecular-weight heparin anti-Xa monitoring.

MEASUREMENTS AND MAIN RESULTS

During the 13-month study period, a total of 6611 patients received enoxaparin for VTE prophylaxis, 301 in the anti-Xa monitored group and 6310 in the unmonitored group (4.6% received monitoring). The mean age was 52.9 years and 52% of patients were male. The mean body mass index was 31 kg/m2 and the mean creatinine clearance was 109 mL/min. Twenty percent of patients had active cancer. The most common indication for enoxaparin prophylaxis was hospitalization for medical illness (52%) followed by nonorthopedic surgery (37%). The adjusted odds ratio for the primary outcome comparing monitored to unmonitored patients was 1.26 (95% confidence interval, 0.75-2.11). None of the between-group differences in the individual components of the composite outcome were statistically significant.

CONCLUSIONS

Thirty-day clinical outcomes in patients receiving enoxaparin for VTE prophylaxis were not improved by anti-Xa monitoring. Our results support current evidence-based guideline recommendations against anti-Xa monitoring for patients receiving enoxaparin for VTE prophylaxis.

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.

Clinical Characteristics and Outcomes of Patients With Venous Thromboembolism Receiving Edoxaban in the Real World

BACKGROUND

The effectiveness and safety of edoxaban for venous thromboembolism (VTE) in unselected real-world patients have not been fully evaluated.Methods and Results: In the Japanese nationwide administrative database, we identified 6,262 VTE patients in whom edoxaban was initiated; these patients were divided into 3 groups based on their index doses: 15 mg/day (n=235), 30 mg/day (n=4,532), and 60 mg/day (n=1,495). We evaluated patient characteristics, recurrent VTEs, and a composite endpoint of intracranial hemorrhage (ICH) and gastrointestinal (GI) bleeding. Patient characteristics among the 15-, 30-, and 60-mg edoxaban groups varied widely regarding several aspects, including age (mean 81.0, 76.2, and 65.0 years, respectively) and body weight (mean 49.5, 51.8, and 70.3 kg, respectively). At 180 days, the cumulative incidence of recurrent VTEs in the 15-, 30-, and 60-mg edoxaban groups was 4.4%, 2.6%, and 1.8%, respectively, whereas that of ICH or GI bleeding was 7.3%, 5.4%, and 3.3%, respectively. Subgroup analyses showed that the cumulative incidence of ICH or GI bleeding in patients in the 15-mg edoxaban group was 3.6% for patients aged ≥80 years, 8.4% for those with a body weight <60 kg, and 31.3% for those with renal dysfunction.

CONCLUSIONS

Only a minority of patients with VTEs received a super low dose (15 mg) of edoxaban, and these patients may be at higher risk of bleeding as well as VTE recurrence.

The History of Extracorporeal Membrane Oxygenation and the Development of Extracorporeal Membrane Oxygenation Anticoagulation

Extracorporeal membrane oxygenation (ECMO) was first started for humans in early 1970s by Robert Bartlett. Since its inception, there have been numerous challenges with extracorporeal circulation, such as coagulation and platelet activation, followed by consumption of coagulation factors and platelets, and biocompatibility of tubing, pump, and oxygenator. Unfractionated heparin (heparin hereafter) has historically been the defacto anticoagulant until recently. Also, coagulation monitoring was mainly based on bedside activated clotting time and activated partial thromboplastin time. In the past 50 years, the technology of ECMO has advanced tremendously, and thus, the survival rate has improved significantly. The indication for ECMO has also expanded. Among these are clinical conditions such as postcardiopulmonary bypass, sepsis, ECMO cardiopulmonary resuscitation, and even severe coronavirus disease 2019 (COVID-19). Not surprisingly, the number of ECMO cases has increased according to the Extracorporeal Life Support Organization Registry and prolonged ECMO support has become more prevalent. It is not uncommon for patients with COVID-19 to be on ECMO support for more than 1 year until recovery or lung transplant. With that being said, complications of bleeding, thrombosis, clot formation in the circuit, and intravascular hemolysis still remain and continue to be major challenges. Here, several clinical ECMO experts, including the "Father of ECMO"-Dr. Robert Bartlett, describe the history and advances of ECMO.

Top 25 Medications the Plastic and Reconstructive Surgery Trainee Should Know for an Emergency Medicine Department Consult

SUMMARY

Plastic surgery trainees are often called to render care in the emergency department (eg, for established patients, trauma, burns). Broad-based knowledge in pharmacotherapeutics during these encounters is critical. This includes an understanding of pain medications, anxiolytics, local anesthetics, antibiotics, anticoagulants, antidotes, and more to ensure optimal patient care. The purpose of this report is to describe 25 frequently used and other important medications that plastic surgery trainees should know for an adult emergency department encounter.

Efficacy and Safety of Rivaroxaban Versus Enoxaparin in Prevention of Recurrence of Venous Thrombo-Embolism Events in Cancer Patients: A Meta-Analysis

OBJECTIVE

To examine the effectiveness of rivaroxaban compared to enoxaparin in patients diagnosed with cancer and venous thromboembolism.

METHODS

A search of Pub Med, Scopus, and Google Scholar, from inception through April 2023 was conducted. Articles comparing rivaroxaban with enoxaparin in patients with cancer and VTE/PE/DVT were included. Review Manager Version 5.2 was utilised for the analysis of the following outcomes; VTE, PE, DVT, major bleeding, and mortality.

RESULTS

A total of 8 articles and 2276 patients were included in the final analysis. Pooled analysis showed that rivaroxaban had a statistically insignificant reduced association with VTE occurrence (RR:0.83, 95% CI:0.58-1.18, P:0.3) as well as a statically insignificant reduction in major bleeding (RR:0.79, 95% CI:0.53-1.18, P:0.25). Analysis showcased that there was an insignificant reduction of mortality rivaroxaban as compared to enoxaparin (RR:0.74, 95% CI: 0.46-1.20, P:0.23).

CONCLUSION

Rivaroxaban can serve as a viable alternative to enoxaparin, with no appreciable drawbacks, for preventing and managing VTE in patients with malignancy.

Use of Andexanet Alfa for Factor Xa Inhibitor Reversal in US Verified Trauma Centers: A National Survey

Direct oral factor Xa inhibitors are replacing vitamin K-dependent antagonists as anticoagulation treatment in many clinical scenarios. Trauma centers are noting an increase in patients presenting on these medications. The 2018 Food and Drug Administration approval of andexanet alfa provides an alternative anticoagulation reversal. Barriers may limit utilization of new medications including a lack of grade 1A evidence supporting the use of prothrombin complex concentrate (PCC) versus andexanet alfa and cost. To evaluate barriers of andexanet alfa utilization by trauma surgeons, a 15-question survey was conducted. There was a 9% completion rate (n = 89). The results revealed 23.5% would choose andexanet alfa as first-line treatment in children, and 25.8% as first-line treatment in adults. The majority of respondents, 64.7% and 67.4%, would use PCC preferentially in children and adults, respectively. Respondents indicated that cost burden was an overriding factor (76.3%); 42.4% cited lack of high-level efficacy data of andexanet alfa for reversal of factor Xa inhibitors. Additional double-blinded multi-institutional randomized controlled trials comparing 4F-PCC and andexanet alfa for factor Xa inhibitor reversal are needed to support efficacy especially with the increased cost associated.

Clinical and biochemical footprints of inherited metabolic disease. XVI. Hematological abnormalities

Many classical inherited metabolic diseases (IMDs) are associated with significant hematological complications such as anemia or thrombosis. While these may not be the prominent presenting feature of these conditions, management of these issues is important for optimal outcomes in people with IMDs. Some disorders that are included in the nosology of inherited metabolic disorders, such as inherited disorders of red cell energy metabolism, have purely hematological features, and have typically been cared for by a hematologist. In the 16th issue of the Footprints series, we identified 265 IMDs associated with hematological abnormalities. We review the major hematological manifestations of IMDs, suggest further investigation of hematological findings, and discuss treatment options available for specific hematological complications of IMDs.

Anticoagulation strategies and long-term recurrence in patients with venous thromboembolism in the era of direct oral anticoagulants

BACKGROUND

There has been limited data on anticoagulation strategies and long-term recurrence in patients with venous thromboembolism (VTE) in the era of direct oral anticoagulant (DOAC).

METHODS

The COMMAND VTE Registry-2 is a multicenter retrospective cohort study enrolling 5197 consecutive patients with acute symptomatic VTE between January 2015 and August 2020 among 31 centers in Japan. In this primary report, the entire cohort was divided into 5 groups; major transient risk factors (N = 475, 9.1%), minor transient risk factors (N = 788, 15%), unprovoked (N = 1913, 37%), non-malignant persistent risk factors (N = 514, 9.9%), and active cancer (N = 1507, 29%) groups.

RESULTS

DOACs were administered in 79% of patients who received oral anticoagulants. Discontinuation of anticoagulant at 1 year was most frequent in the major transient risk factors group (57.2%, 46.3%, 29.1%, 32.0%, and 45.6%). The cumulative 5-year incidence of recurrent VTE was lowest in the major transient risk factors group (2.6%, 6.4%, 11.0%, 12.1%, and 10.1%, P < 0.001). The cumulative 5-year incidence of major bleeding was highest in the active cancer group (9.8%, 11.4%, 11.0%, 15.5%, and 20.4%, P < 0.001). After discontinuation of anticoagulation therapy, the cumulative 5-year incidence of recurrent VTE was highest in the unprovoked group (3.3%, 11.0%, 24.9%, 17.5%, and 11.8%, P < 0.001).

CONCLUSIONS

In this large real-world VTE registry, anticoagulation strategies and long-term recurrence widely differed depending on the baseline characteristics. Detailed risk stratifications of recurrent VTE could be useful for decision-making of anticoagulation strategies, whereas the bleeding-risk assessment might be especially important in the era of DOAC.

CLINICAL TRIAL REGISTRATION

URL: http://www.umin.ac.jp/ctr/index.htm Unique identifier: UMIN000044816.

Global Research Hotspots in Venous Thromboembolism Anticoagulation: A Knowledge-Map Analysis from 2012 to 2021

Background

Venous thromboembolism (VTE) is a common cardiovascular disease that seriously threatens human lives. Anticoagulant therapy is considered to be the cornerstone of VTE treatment. An increasing number of studies has been updated in the VTE anticoagulation field. However, no bibliometric analyses have assessed these publications comprehensively. Therefore, our study aimed to analyze the global status, hotspots, and trends of anticoagulant therapy for VTE.

Methods

The relevant literature on VTE anticoagulation published between 2012 and 2021 was retrieved and collected from the Web of Science Core Collection database. VOSviewer, Cooccurrence Matrix Builder, gCLUTO, and some online visualization tools were adopted for bibliometric analysis.

Results

A total of 15,152 related articles were retrieved. In recent years, the research output of VTE anticoagulation gradually increased. The United States was the most productive country. International cooperation is concentrated in North America and Europe; the most influential documents, journals, authors, and organizations were also from these two continents. Research hotspots mainly focus on clinical guidelines, VTE in special populations, non-vitamin K oral anticoagulants (NOACs), and parenteral anticoagulation. The research frontiers and trends include the assessment of NOACs and the antithrombotic management of VTE complicated with coronavirus disease 2019 (COVID-19).

Conclusion

This bibliometric analysis provides a systematic overview of the VTE anticoagulation research, which will facilitate researchers to better understand the situation of VTE anticoagulation. Future studies should be dedicated to NOACs application and VTE-combined COVID-19 patients.

Implementation and evaluation of a warfarin patient self-management (PSM) program among experienced patients in a U.S. academic health system

Warfarin patient self-management (PSM) is when a patient independently manages their warfarin therapy using a decision-support tool provided by their anticoagulation provider. Clinical trials of PSM, conducted predominantly in Europe, have consistently demonstrated superior efficacy without compromising safety. However, the evidence-based practice of PSM is rarely utilized in the United States (U.S.). We describe initiatives completed to implement a successful PSM program among experienced warfarin-taking patients in a U.S. academic health system by overcoming perceived barriers. The results showed PSM resulted in similar or improved INR control, and an estimated 68% reduction in pharmacist workload.

The effect of renal impairment and obesity on anti-Xa peak and trough levels in patients receiving therapeutic doses of nadroparin: a comparison with control patients

PURPOSE

Anti-Xa peak level monitoring is recommended during LMWH treatment in renal impairment or obesity. The trough level has been proposed as marker for bleeding. We studied the influence of renal impairment and obesity on anti-Xa levels.

METHODS

Peak and trough levels were collected during therapeutic nadroparin treatment in patients with renal impairment, obese patients, and controls. 27 patients (n = 68 samples) were evaluated and combined with published data (n = 319 samples from 35 patients) using population pharmacokinetic (popPK) modelling.

RESULTS

Median peak level was 0.44 and 0.95 IU/mL in renal impairment with and without dose reduction and 0.60 and 0.43 IU/mL in obesity and controls, respectively. Trough levels were < 0.5 IU/mL in all patients with renal impairment with dose reduction and in 5/6 control patients. In the popPK model, total body weight and eGFR were covariates for clearance and lean body weight for distribution volume. Model-based evaluations demonstrated peak levels below the therapeutic window in controls and increased levels in renal impairment. Dose reductions resulted in a different effect on peak and trough levels. Obese patients (BMI up to 32 kg/m2) had similar levels upon weight-based dosing.

CONCLUSION

In renal impairment, anti-Xa peak levels after dose reduction are comparable to those in controls. Weight-based dosing is suitable for obese patients. Aiming for peak levels between 0.6 and 1.0 IU/mL in these patients would result in overexposure compared to controls. Considering the association of trough levels and bleeding risk and our findings, trough monitoring seems to be a suitable parameter to identify nadroparin accumulation.

Comparison of outcomes for fixed and weight-based four-factor prothrombin complex concentrate dosing regimens

OBJECTIVES

Although fixed dose regimens using four-factor prothrombin complex concentrate (4F-PCC) are more widely accepted, using a 'one size fits all' approach remains an area of uncertainty. The primary objective of this study was to compare percentages of haemostasis between fixed dose and weight-based dose 4F-PCC regimens for multiple bleed types and anticoagulants. Secondary objectives compared differences in the time to administration and in-hospital mortality.

METHODS

This retrospective, cohort study took place at a community hospital and included patients ≥18 years of age receiving 4F-PCC for major bleeding while on either warfarin or a factor-Xa inhibitor between January 2015 and December 2022. Patients received either fixed dose (treatment) or weight-based dose (comparison). Patients who had been treated for a non-urgent procedure, with unknown haemorrhage source, not on anticoagulation, coagulopathic from hepatic failure, had received dabigatran or were allergic to heparin were excluded. Fisher's exact test and logistic regression were used to analyse primary and secondary outcomes.

RESULTS

94 patients met the inclusion criteria; 38 patients were assigned to the treatment group and 56 to the comparator group. There was no statistical evidence of a difference in the achievement of haemostasis between groups (45% vs 46%, p=0.872). The fixed dose patients received the dose on average 13 min faster than weight-based (32 min vs 46 min, p=0.031). There was no difference in mortality (29% vs 29%, p=0.968).

CONCLUSION

Fixed 4F-PCC regimens may achieve similar outcomes and a faster time to administration compared with weight-based regimens.

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

Direct oral anticoagulants (DOACs) are widely used for the prevention and treatment of venous thromboembolism and stroke. When emergency reversal of DOAC-related anticoagulation is required, specific DOAC reversal agents are recommended, including idarucizumab for dabigatran reversal and andexanet alfa for apixaban and rivaroxaban reversal. However, specific reversal agents are not always available, andexanet alfa has not been approved for urgent surgery, and clinicians need to know the patient's anticoagulant medication before administering these treatments. Four-factor prothrombin complex concentrates (4F-PCCs) are recognized as nonspecific, alternative hemostatic agents for treatment of DOAC-related bleeding. Evidence from preclinical and clinical studies shows that they may reduce the anticoagulant effects of DOACs and may help control DOAC-related bleeding. However, randomized controlled trials are lacking, and most data are from retrospective or single-arm prospective studies in bleeding associated with activated factor X inhibitors. There are no clinical data showing the efficacy of 4F-PCC for the treatment of bleeding in dabigatran-treated patients. This review focuses on the current evidence of 4F-PCC use in controlling bleeding associated with DOACs and provides an expert opinion on the relevance of these data for clinical practice. The current treatment landscape, unmet needs, and future directions are also discussed.

Optimal length of oral anticoagulant treatment for maximum benefit within 5 years after discontinuation of oral anticoagulants in patients with acute pulmonary embolism who require secondary thromboprophylaxis

BACKGROUND

Extended oral anticoagulant (OA) use is recommended in patients with acute pulmonary embolism (PE) who require secondary thromboprophylaxis. Nevertheless, the optimal length of OA use for the maximum long-term benefit in this patient population has been undefined to date.

METHODS

A retrospective study was performed to explore the role of different length of overall OA use (group 1 (≥1 year of OA use and <2 years of OA use), group 2 (≥2 years of OA use and <3 years of OA use), group 3 (≥ 3 years of OA use)) in outcomes within 5 years after OA discontinuation in patients with acute PE, who required secondary thromboprophylaxis. The primary outcome was mortality rates. The secondary outcomes comprised venous thromboembolism (VTE) recurrence, major bleeding during OA use and net clinical benefit. Net clinical benefit was defined as the composite of recurrent VTE and major bleeding.

RESULTS

For a total of 385 patients in group 1 (n=220), group 2 (n=110) and group 3 (n=55), the PE-related mortality in group 1 was higher than that in group 2 (p=0.034) and 3 (p=0.040), respectively, whereas were similar between groups 2 and 3 (p=1.000). The net clinical benefit in group 1 was less than that in group 2 (p=0.024), whereas similar with that in group 3 (p=0.526). The net clinical benefit was comparable between groups 2 and 3 (p=0.716). The length of OA use was positively associated with major bleeding (HR, 2.510 (0.293 to 3.485), p=0.001), whereas negatively associated with PE-related mortality (HR, 0.668 (0.196 to 2.832), p=0.025) and VTE recurrence (HR, 0.694 (0.174 to 2.300), p=0.036), respectively. The sensitivity and specificity of the length of OA use for the tendency of PE-related mortality was 70.2% and 46.2%, respectively. The area under the curve (AUC) was 0.654 (0.514 to 0.793) (p=0.029). The sensitivity and specificity of the length of OA use for the tendency of net clinical benefit was 86.8% and 64.3%, respectively. The AUC was 0.628 (0.565 to 0.690) (p<0.001) CONCLUSIONS: For patients with acute PE who require secondary thromboprophylaxis, 2 to 3 years (30 months preferred) of overall OA use after a diagnosis of acute PE could be an optimal length to achieve maximum benefit within 5 years after OA discontinuation.

Recommendations for the use of andexanet alfa in the management of bleeding in patients on oral factor Xa inhibitors in Switzerland: Guideline from the Working Party Hemostasis of the Swiss Society of Hematology

Anticoagulants are essential in preventing and treating thrombosis. Unfortunately, their use is accompanied by an enhanced risk of bleeding. Since the introduction of direct oral anticoagulants (DOACs), the risk of major bleeding has been reduced but not eliminated. Major bleeding events related to the use of factor Xa inhibitors can be challenging to manage. In recent years, four-factor prothrombin complex concentrates have been used in patients with severe bleeding taking oral direct factor Xa inhibitors (apixaban, edoxaban and rivaroxaban). Andexanet alfa (OndexxyaTM, AstraZeneca AG) is a specially designed recombinant version of human factor Xa that acts as a decoy receptor to reverse the effects of factor Xa inhibitors. Since 2 December 2020, andexanet alfa has been used in Switzerland for adult patients receiving apixaban or rivaroxaban when reversal of anticoagulation is required because of life-threatening or uncontrolled bleeding. However, the use of andexanet alfa remains a challenge owing to its cost, the reported thrombotic complications and the fact that its efficacy mainly relates to intracranial haemorrhage. Moreover, the use of nonspecific reversal agents together with andexanet alfa is controversial. The present recommendations on the use of andexanet alfa in the management of bleeding in patients on factor Xa inhibitors in Switzerland were developed by a group of Swiss experts from the Working Party Hemostasis of the Swiss Society of Hematology. These recommendations aim to provide support to clinicians in their decision-making in the management of patients with major bleeding receiving factor Xa inhibitors.

Antithrombin III deficiency in a patient with recurrent venous thromboembolism: A case report

BACKGROUND

Antithrombin III (AT3) deficiency, an autosomal dominant disease, increases the likelihood of an individual developing venous thromboembolism (VTE). Long-term anticoagulation treatment is required for those suffering from AT3 deficiency.

CASE SUMMARY

A man aged 23, who had a history of deep venous thrombosis (DVT), experienced recurrent pain and swelling in his right lower extremity for three days following withdrawal of Rivaroxaban. He was diagnosed with DVT and antithrombin III deficiency as genetic testing revealed a single nucleotide variant in SERPINC1 (c.667T>C, p.S223P). The patient was advised to accept long-term anticoagulant therapy.

CONCLUSION

Inherited AT3 deficiency due to SERPINC1 mutations results in recurrent VTE. Patients may benefit from long-term anticoagulant therapy.

Indefinite Anticoagulant Therapy for First Unprovoked Venous Thromboembolism : A Cost-Effectiveness Study

BACKGROUND

Clinical practice guidelines recommend indefinite anticoagulation for a first unprovoked venous thromboembolism (VTE).

OBJECTIVE

To estimate the benefit-harm tradeoffs of indefinite anticoagulation in patients with a first unprovoked VTE.

DESIGN

Markov modeling study.

DATA SOURCES

Systematic reviews and meta-analyses for the long-term risks and case-fatality rates of recurrent VTE and major bleeding. Published literature for costs, quality of life, and other clinical events.

TARGET POPULATION

Patients with a first unprovoked VTE who have completed 3 to 6 months of initial anticoagulant treatment.

TIME HORIZON

Lifetime.

PERSPECTIVE

Canadian health care public payer.

INTERVENTION

Indefinite anticoagulation with direct oral anticoagulants.

OUTCOME MEASURES

Recurrent VTE events, major bleeding events, costs in 2022 Canadian dollars (CAD), and quality-adjusted life-years (QALYs).

RESULTS OF BASE-CASE ANALYSIS

When compared with discontinuing anticoagulation after initial treatment in a hypothetical cohort of 1000 patients aged 55 years, indefinite anticoagulation prevented 368 recurrent VTE events, which included 14 fatal pulmonary emboli, but induced an additional 114 major bleeding events, which included 30 intracranial hemorrhages and 11 deaths from bleeding. Indefinite anticoagulation cost CAD $16 014 more per person and did not increase QALYs (-0.075 per person).

RESULTS OF SENSITIVITY ANALYSIS

Model results were most sensitive to the case-fatality rate of major bleeding and the annual risk for major bleeding during extended anticoagulation.

LIMITATION

The model assumed that risks for recurrent VTE and major bleeding measured in clinical trials at 1 year remained constant during extended anticoagulation.

CONCLUSION

Clinicians should use shared decision making to incorporate individual patient preferences and values when considering treatment duration for unprovoked VTE.

PRIMARY FUNDING SOURCE

Canadian Institutes of Health Research.

Acquired Hemophilia A Masquerading as Bleeding on Anticoagulation: A Case Report Including Key Laboratory Considerations

We report a case of a patient with recurrent hematomas while on anticoagulation for a pulmonary embolism and a prolonged hospital stay due to a delayed diagnosis for acquired hemophilia A. Acquired hemophilia A is a rare autoimmune bleeding disorder with autoantibodies directed against coagulation factor VIII (FVIII), leading to an acquired FVIII deficiency. A prolonged isolated activated partial thromboplastin time (aPTT) in a bleeding patient warrants workup for acquired hemophilia A. This is specifically challenging in patients with thrombosis on anticoagulation and can lead to significant delays in diagnosis and associated morbidities. The case highlights the need for further awareness of this disease, potential laboratory pitfalls when conducting and interpreting coagulation assays, and the management considerations in a patient with a simultaneous thrombotic and hemorrhagic condition.

The right time to measure anti-Xa activity in critical illness: pharmacokinetics of therapeutic dose nadroparin

Background

Peak anti-Xa activity of low-molecular-weight heparin nadroparin is measured 3 to 5 hours after subcutaneous injection. In critically ill patients, physiological changes and medical therapies may result in peak activities before or after this interval, possibly impacting dosing.

Objectives

The primary objective was to determine the percentage of critically ill patients with adequately estimated peak activities drawn 3 to 5 hours after subcutaneous administration of a therapeutic dose of nadroparin. Adequate was defined as a peak activity of ≥80% of the actual peak anti-Xa activity. If ≥80% of patients had adequately estimated peak activities in the 3- to 5-hour interval, measurement in this interval was regarded as acceptable. The secondary objective was to determine the pharmacokinetic profile of nadroparin.

Methods

In this single-center, prospective study, we evaluated anti-Xa activities in patients admitted to a general intensive care unit. After ≥4 equal doses of nadroparin, anti-Xa activity was measured according to a 12- to 24-hour sampling scheme.

Results

In 25 patients, anti-Xa activities drawn between 3 and 5 hours after administration ranged 80% to 100% of the actual peak activity. Compared to the threshold level of an adequate estimation in at least 20 patients (≥80%), measuring anti-Xa activities in the 3- to 5-hour interval is an acceptable method (1-tailed binomial test; P < .02). We found a large interindividual variability for nadroparin exposure (mean ± SD area-under-the-curve_0-12h, 10.3 ± 4.8 IU·h/mL) and delayed elimination (t_1/2 range, 4.0-120.9 hours) despite adequate renal function.

Conclusion

In critically ill patients, measuring anti-Xa activity in a 3- to 5-hour interval after subcutaneous injection of therapeutic nadroparin is an acceptable method to estimate the actual peak anti-Xa activity.

UpdatED: The emergency medicine pharmacotherapy literature of 2022

The purpose of this article is to summarize pharmacotherapy related emergency medicine (EM) literature indexed in 2022. Articles were selected utilizing a modified Delphi approach. The table of contents from pre-determined journals were reviewed and independently evaluated via the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system by paired authors, with disagreements adjudicated by a third author. Pharmacotherapy-related publications deemed to be GRADE 1A and 1B were reviewed by the group for inclusion in the review. In all, this article summarizes and provides commentary on the potential clinical impact of 13 articles, 4 guidelines, and 3 meta-analyses covering topics including anticoagulant reversal, tenecteplase in acute ischemic stroke, guideline updates for heart failure and aortic aneurysm, magnesium in atrial fibrillation, sedation in mechanically ventilated patients and pain management strategies in the Emergency Department (ED), and tranexamic acid use in epistaxis and GI bleed.

Periprocedural Anticoagulation

Management of patients taking anticoagulants around the time of a procedure is a common and complex clinical scenario. Providing evidence-based care requires estimation of risk for thrombosis and bleeding, knowledge of commonly used medications, multidisciplinary communication and collaboration, and patient engagement and education. This review provides a standardized, evidence-based approach to periprocedural management of anticoagulation, based on current evidence and expert clinical guidelines.

A scoping review of direct oral anticoagulant ambulatory management practices

Models of care for managing direct oral anticoagulant (DOAC) therapy are evolving. Little is known of what services are provided by anticoagulation managements services (AMS) for DOACs, or what necessitates comprehensive DOAC management and what differentiates it from usual care. The purpose of this scoping review was to describe services, management, or monitoring of DOACs distinct from prescriber-managed or usual care of DOACs. This scoping review reported followed the 2018 Preferred Reporting Items for Systematic Review and Meta-Analyses extension for scoping reviews (PRISMA-ScR). We searched PubMed, CINAHL, and EMBASE from inception to November 2020 to identify articles of interest. No language restriction was applied. Articles were included if they provided a description of DOAC management services, and described longitudinal anticoagulation follow-up that occurred in ambulatory care, community, or outpatient-related settings. Data was extracted from a total of 23 articles. The specific types of DOAC management interventions provided varied across the included studies. Nearly all studies described some form of DOAC therapy appropriateness assessment. Other common interventions included assessments of DOAC therapy compliance, adverse event triage and management, assessment of DOAC dosing appropriateness, periprocedural management of DOAC therapy, educational interventions, and renal function monitoring. A variety of DOAC management interventions were identified, but additional studies are needed to help health systems decide whether specific interventions performed by dedicated services are preferred over the usual care provided by clinicians prescribing DOAC therapy.