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

Relevant pharmacologic interactions in the concurrent management of brain tumor-related epilepsy and venous thromboembolism: a systematic review

INTRODUCTION

Co-administration of direct oral anticoagulants (DOACs) with antiepileptic drugs (AEDs) is increasingly common in brain tumor patients. We therefore performed a systematic review of the current evidence for potential drug interactions between DOACs and AEDs in this patient population.

METHODS

We conducted a systematic review of the literature via PubMed according to PRISMA guidelines (last accessed December 15, 2021). Included were clinical studies and case reports, written in English language and published between 2010 and 2021, that investigated concurrent clinical use of AEDs with DOACs for any indication. Non-English articles, articles not related to our research question, review articles and commentaries were excluded. Full-text articles were evaluated for possible confounding factors and results were summarized using a data table highlighting the key characteristics of each article.

RESULTS

We identified a total of 122 unique articles, of which 27 were deemed relevant to our research question. Of these, 8 articles were clinical studies (n = 295,415 patients) and 19 were case reports (n = 25 patients). Only 3 clinical studies and 2 case reports reported interactions between AEDs and DOACs in patients with active cancer and none reported interactions in patients with brain tumors.

CONCLUSION

We have identified low (class IV) level evidence of potential drug interactions between DOACs and AEDs. Even though there is no current report of interactions in brain tumor patients, neuro-oncology providers should be aware of the emerging evidence regarding drug interactions between DOACs and AEDs and take this into consideration when concurrently prescribing these to patients.

Four-factor prothrombin complex concentrate plus andexanet alfa for reversal of factor Xa inhibitor-associated bleeding: Case series

DISCLAIMER

In an effort to expedite the publication of articles related to the COVID-19 pandemic, AJHP is posting these manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

PURPOSE

To manage factor Xa (FXa) inhibitor-associated bleeding, andexanet alfa or 4-factor prothrombin concentrate (4F-PCC) has been used to restore hemostasis. However, literature on the outcomes for patients who received both andexanet alfa and 4F-PCC is limited.

SUMMARY

We report a case series of 5 patients who received andexanet alfa plus 4F-PCC for reversal of FXa inhibitor-associated bleeding. Patients were included in this case series if they received both andexanet alfa and 4F-PCC for reversal of FXa inhibitor-associated bleeding. They were followed to either discharge or death, and in-hospital complications related to concurrent use of andexanet alfa and 4F-PCC were documented. We report an incidence of thromboembolism of 40% (2 of 5 cases) and an in-hospital mortality rate of 60% (3 of 5 cases). Taking these cases together with those in the existing literature, we found a total of 23 reported cases of safety outcomes with andexanet alfa plus 4F-PCC. The overall incidence of thromboembolism was 35% (8 of 23 cases).

CONCLUSION

This case series adds to the limited literature describing the outcomes for patients receiving andexanet alfa plus 4F-PCC. We encourage other institutions to report safety data on administering both agents.

Pharmacist monitoring of direct oral anticoagulants for American Indians and Alaska Natives in the outpatient setting

BACKGROUND

Direct oral anticoagulants (DOACs) call into question the role of traditional pharmacist-run clinics, and few studies have described the incorporation of DOAC's into traditional anticoagulation management services (AMS) OBJECTIVE: To describe the incorporation of DOACs into a pharmacist-run AMS for American Indian and Alaska Native (AI/AN) patients and determine outcomes related to adherence, follow-up, and pharmacist interventions.

PRACTICE DESCRIPTION

Traditional AMS embedded in ambulatory clinic. Warfarin managed by pharmacists under a collaborative practice agreement with supervising physician.

PRACTICE INNOVATION

DOACs incorporated into AMS by transitioning warfarin patients to rivaroxaban and apixaban and managing new patients with DOAC. Follow-up occurred via phone call and at longer intervals.

EVALUATION METHODS

Single-center, retrospective, observational analysis of AI/AN patients who were followed up by pharmacy AMS. The outcomes measured include adherence to DOAC therapy, number of telephonic encounters versus face-to-face visits, frequency of follow-up, types of interventions made at each visit, and an estimate of face-to-face clinic time savings.

RESULTS

A total of 50 patients were included for analysis. The average medication possession ratio was 91%. The majority of visits occurred over the phone (59%), and most follow-up visits occurred every 3 months (62%). The top 3 most frequent interventions were adherence education, initial DOAC education, and education on use of nonsteroidal anti-inflammatory drugs.

PRACTICE IMPLICATIONS

Traditional AMS can evolve by incorporating DOACs and maintaining follow-up.

CONCLUSION

Pharmacist monitoring of DOACs may promote high levels of adherence and lead to time savings by reducing the amount of time spent in traditional AMS.

[What the (general and abdominal) surgeon should know about thrombosis prophylaxis]

A persisting problem in the clinical operative routine is surgery-associated venous thromboembolisms with the possible complications. The competent and reliably realized prophylaxis of thromboembolism is part of the original and elementary tasks of the surgeon, both the operator as well as the clinically active physician. Many preventive approaches were developed and established in the daily management but a residual risk for development of thrombosis still remains. Under this aspect a search was carried out particularly with respect to scientific literature with review and guideline character on the topic of risk stratification, prophylactic procedures in general and for specific indications.

Therapeutic-Dose Warfarin (International Normalized Ratio >1.6) Plus Aspirin Improved Long-Term Patency of Saphenous Vein Graft without Bleeding Complication

Purpose: Saphenous vein graft (SVG) is the most commonly used conduits in coronary artery bypass grafting (CABG), but the disadvantage of SVG is its tendency for progressive failure. We hypothesized that therapeutic-dose warfarin (international normalized ratio [INR] >1.6) plus aspirin improve SVG patency. This study aimed to evaluate the factors contributing to SVG patency.

Methods: Since 2010–2020, 199 patients who underwent isolated CABG using SVG were divided into two groups according to their INR values in the first year: group T (INR >1.6) and group L (INR <1.6).

Results: Group T had 162 SVGs (105 patients) and group L had 151 SVGs (94 patients). The 1-, 4-, and 7-year SVG patency rates were higher in group T than in group L (99%, 96%, and 92% vs. 93%, 86%, and 79%, respectively; p = 0.00378). The 1-, 4-, and 7-year freedom from repeat-revascularization was higher in group T than in group L (100%, 100%, and 99% vs. 98%, 95%, and 87%, respectively; p = 0.0264). Multivariate analysis showed that therapeutic-dose warfarin (p = 0.00204) and target vessel diameter (p <0.0001) were independent risk factors of SVG occlusion.

Conclusion: Therapeutic-dose warfarin (INR >1.6) plus aspirin after CABG improved the long-term patency of SVG and decreased repeat-revascularization rate.

The VKORC1 and CYP2C9 gene variants as pharmacogenetic factors in acenocoumarol therapy in Serbian patients - consideration of hypersensitivity and resistance

Introduction/Objective. Coumarin therapy represents one of the best models for applying pharmacogenetics. The contribution of factors influencing coumarin therapy can vary significantly between ethnic groups, which justifies conducting population-specific studies. The aim of this study was to analyze the influence of the most important genetic factors (VKORC1 and CYP2C9 genes) that affect coumarin therapy in patients from Serbia. Methods. A retrospective study involving 207 patients on acenocoumarol therapy was conducted. Genetic analyses were performed by direct sequencing. Influence on acenocoumarol dose of variants (VKORC1, CYP2C9*2, CYP2C9*3) causing hypersensitivity and VKORC1 variants causing resistance to acenocoumarol were analyzed. Multiple regression analysis was used to design a mathematical model for predicting individual drug dosage based on clinical-demographic and genetic data. Results. The study confirmed significant influence of the analyzed genetic factors on acenocoumarol maintenance dose. We designed mathematical model for predicting individual acenocoumarol dose and its unadjusted R2 was 61.8. In the testing cohort, our model gave R2 value of 42.6 and showed better prediction in comparison with model given by other authors. In the analyzed patients, nine different variants in the VKORC1 coding region were found. Among carriers of these variants 78% were completely resistant, and it was not possible to achieve therapeutic effect even with high doses of acenocoumarol. Conclusions. Population-specific model for prediction individual dose of acenocoumarol, may show advantages over protocols that are used in a generalized manner. Also, VKORC1 variants which cause coumarin resistance should be considered when planning therapy.

Hormone Therapy in the Era of the COVID-19 Pandemic: A Review

The coronavirus disease 2019 (COVID-19) pandemic has impacted the medical, social, and reproductive health of millions of people since its outbreak. The causative virus transmits, reproduces, and manifests through the respiratory tract. COVID-19 can invade any system of the body, including the cardiovascular and endocrine systems, through a secondary immune response. In particular, because the fatality rate is high in those over the age of 50 years, special attention is required during the medical care of this population. However, considering the benefit of therapy and the risk of COVID-19, high-quality evidence regarding individualized management in relation to hormone therapy is still insufficient in the field of gynecology. Furthermore, this review aims to serve as a reference for clinical application by analyzing and summarizing the results of studies reported to date regarding female hormone therapy in the context of the COVID-19 pandemic.

Relevance of Non-Bridging Therapy with Heparin during Temporary Interruption of Direct Oral Anticoagulants in Patients with Cancer-Associated Venous Thromboembolism

Objectives: To evaluate the relevance of non-bridging therapy with unfractionated heparin during the temporary, pre-procedural interruption of direct oral anticoagulants (DOACs) in patients with cancer-associated venous thromboembolism (VTE).

Materials and Methods: This retrospective study included 142 patients with cancer and VTE who required temporary interruption of DOACs before invasive procedures. Data, including rates of VTE recurrence, non-major bleeding, and major bleeding, were compared between patients who received or not received alternative therapy with unfractionated heparin during interruption.

Results: Sixty-eight patients were prescribed heparin, while 74 were not. There were no differences in age, body mass index, white blood cell count, hemoglobin level, or platelet count between the groups. VTE recurrence was observed in four (6%) and one (1%) patient in the heparin bridging and non-bridging groups, respectively (risk ratio [RR]: 4.4, 95% confidence interval [CI]: 0.50–38.0, p=0.19). Non-major bleeding occurred in three (4%) and two (3%) patients in the bridging and non-bridging groups (RR: 1.6, 95%CI: 0.28–9.48, p=0.67), while major bleeding occurred in 0 (0%) and three patients (4%) (p=0.25), respectively.

Conclusion: Our findings confirm the relevance of non-bridging therapy with unfractionated heparin for reducing VTE risk during DOAC interruption in patients with cancer.

Effects of dalteparin on anti-Xa activities cannot be predicted in critically ill COVID-19 patients

Critically ill COVID‐19 patients are at high risk of thromboembolic events despite routine‐dosed low‐molecular‐weight heparin thromboprophylaxis. However, in recent randomized trials increased‐intensity thromboprophylaxis seemed futile and possibly even harmful. In this explorative pharmacokinetic (PK) study we measured anti‐Xa activities on frequent timepoints in 15 critically ill COVID‐19 patients receiving dalteparin and performed PK analysis by nonlinear mixed‐effect modelling. A linear one‐compartment model with first‐order kinetics provided a good fit. However, wide interindividual variation in dalteparin absorption (variance 78%) and clearance (variance 34%) was observed, unexplained by routine clinical covariates. Using the final PK model for Monte Carlo simulations, we predicted increased‐intensity dalteparin to result in anti‐Xa activities well over prophylactic targets (0.2‐0.4 IU/mL) in the majority of patients. Therapeutic‐intensity dalteparin results in supratherapeutic anti‐Xa levels (target 0.6‐1.0 IU/mL) in 19% of patients and subtherapeutic levels in 22%. Therefore, anti‐Xa measurements should guide high‐intensity dalteparin in critically ill COVID‐19 patients.

Differential Presentations of Arterial Thromboembolic Events Between Venous Thromboembolism and Atrial Fibrillation Patients

Objective: Atrial fibrillation (AF) and venous thromboembolism (VTE) share several risk factors related to arterial thromboembolism. No study has reported the differential contribution to arterial thromboembolic events and mortality between these two conditions in the same population. We therefore assessed the differential arterial thromboembolic events between AF and VTE.

Methods: We included AF and VTE national cohorts derived from Taiwan National Health Insurance Research Database between 2001 and 2013. The eligible population was 314,861 patients in the AF cohort and 41,102 patients in the VTE cohort. The primary outcome was arterial thromboembolic events, including ischemic stroke, extracranial arterial thromboembolism (ECATE) and myocardial infarction (MI). Secondary outcomes were all-cause mortality and cardiovascular death.

Results: After a 1:1 propensity matching, 32,688 patients in either group were analyzed. The risk of arterial thromboembolic events was lower in the VTE cohort than that in the AF cohort (subdistribution hazard ratio [SHR], 0.60; 95% confidence interval [CI], 0.57–0.62). The risk of ischemic stroke (SHR, 0.44; 95% CI, 0.42–0.46) and MI (SHR, 0.80; 95% CI, 0.72–0.89) were lower in the VTE cohort, while the risk of ECATE (SHR, 1.23; 95% CI, 1.14–1.33; particularly lower extremities) was higher in the VTE cohort. All-cause mortality rate was higher in the VTE cohort (HR, 1.18; 95% CI, 1.15–1.21) while the risk of cardiovascular death was lower in the VTE cohort (HR, 0.96; 95% CI, 0.93–0.995).

Conclusions: Patients with AF had higher risks of arterial thromboembolic events compared to patients with VTE, despite having risk factors in common. The VTE cohort had higher risks of all-cause mortality and ECATE, particularly lower extremity events, compared to AF patients. The differential manifestations of thromboembolism sequelae and mortality between AF and VTE patients merit further investigation.

Management of Coagulopathy in Bleeding Patients

Early recognition of coagulopathy is necessary for its prompt correction and successful management. Novel approaches, such as point-of-care testing (POC) and administration of coagulation factor concentrates (CFCs), aim to tailor the haemostatic therapy to each patient and thus reduce the risks of over- or under-transfusion. CFCs are an effective alternative to ratio-based transfusion therapies for the correction of different types of coagulopathies. In case of major bleeding or urgent surgery in patients treated with vitamin K antagonist anticoagulants, prothrombin complex concentrate (PCC) can effectively reverse the effects of the anticoagulant drug. Evidence for PCC effectiveness in the treatment of direct oral anticoagulants-associated bleeding is also increasing and PCC is recommended in guidelines as an alternative to specific reversal agents. In trauma-induced coagulopathy, fibrinogen concentrate is the preferred first-line treatment for hypofibrinogenaemia. Goal-directed coagulation management algorithms based on POC results provide guidance on how to adjust the treatment to the needs of the patient. When POC is not available, concentrate-based management can be guided by other parameters, such as blood gas analysis, thus providing an important alternative. Overall, tailored haemostatic therapies offer a more targeted approach to increase the concentration of coagulation factors in bleeding patients than traditional transfusion protocols.

Perioperative consultative hematology: can you clear my patient for a procedure?

Periprocedural management of antithrombotics is a common but challenging clinical scenario that renders patients vulnerable to potential adverse events such as bleeding and thrombosis. Over the past decade, periprocedural antithrombotic approaches have changed considerably with the advent of direct oral anticoagulants (DOACs), as well as a paradigm shift away from bridging in many warfarin patients. Successfully navigating this high-risk period relies on a number of individualized patient assessments conducted within a framework of standardized, systematic approaches. It also requires a thorough understanding of antithrombotic pharmacokinetics, multidisciplinary coordination of care, and comprehensive patient education and empowerment. In this article, we provide clinicians with a practical, stepwise approach to periprocedural management of antithrombotic agents through case-based examples of relevant clinical scenarios.

New methods facilitated the process of prioritizing questions and health outcomes in guideline development

BACKGROUND

Health guideline development requires sequential prioritization of the guideline topic, questions, and health outcomes. In this paper we report on new approaches for prioritizing questions and outcomes in guidelines.

METHODS

Ten guideline panels on venous thromboembolism rated potential guideline questions on a 9-point scale according to their overall importance and 6 criteria: common in practice, uncertainty in practice, variation in practice, new evidence available, cost consequences, not previously addressed. We randomized panelists to rate one potential question with and without the 6 criteria. Panelists rated importance of outcomes, defined with health outcome descriptors (HODs), using a 9-point scale, and health utility of outcomes on a visual analogue scale.

RESULTS

Of 469 potential questions identified, 72.5% were rated as important but not of high priority, and 25.4% as high priority. Each criterion was significantly associated with the overall importance rating. The overall importance rating means were 5.96 (SD 2.38) and 6.53 (SD 2.45) (P = 0.25) for those randomized to rate questions with and without the criteria, respectively. The mean importance rating for 121 outcomes was 6.01 (SD 1.25), with 35.5% rated as critical for decision-making. Panelists provided health utility ratings for 127 outcomes, with a minimum mean rating of 0.12 (SD 0.10) and maximum of 0.91 (SD 0.15).

CONCLUSION

Our structured process provided information to help explain perspectives of question importance, to facilitate panels' outcome prioritization, and to facilitate decision-making in guideline development.

Anticoagulation Treatment in Venous Thromboembolism: Options and Optimal Duration

Venous thromboembolism (VTE), clinically presenting as deep-vein thrombosis (DVT) or pulmonary embolism (PE), constitutes a major global healthcare concern with severe complications, long-term morbidity and mortality. Although several clinical, genetic and acquired risk factors for VTE have been identified, the molecular pathophysiology and mechanisms of disease progression remain poorly understood. Anticoagulation has been the cornerstone of therapy for decades, but there still are uncertainties regarding primary and secondary VTE prevention, as well as optimal therapy duration. In this review we discuss the role of factor Xa in coagulation cascade and the different choices of anticoagulation therapy based on patients' predisposing risk factors and risk of event recurrence. Further, we compare newer agents to traditional anticoagulation treatment, based on most recent studies and guidelines.

Anticoagulant Reversal in Gastrointestinal Bleeding: Review of Treatment Guidelines

BACKGROUND

Patients receiving anticoagulant therapies, such as vitamin K antagonists (VKAs) or direct oral anticoagulants (DOACs), commonly experience gastrointestinal (GI) bleeding as a complication and may require anticoagulant reversal prior to endoscopic treatment. Anticoagulant reversal agents include prothrombin complex concentrates (PCCs; including 3 or 4 coagulation factors), plasma, vitamin K, and target-specific DOAC reversal agents (e.g., idarucizumab and andexanet alfa).

AIM

To review current US, as well as international, guidelines for anticoagulant reversal agents in patients on VKAs or DOACs presenting with GI bleeding prior to endoscopy, guideline-based management of coagulation defects, timing of endoscopy, and recommendations for resumption of anticoagulant therapy following hemostasis. Supporting clinical data were also reviewed.

METHODS

This is a narrative review, based on PubMed and Internet searches reporting GI guidelines and supporting clinical data.

RESULTS

GI-specific guidelines state that use of reversal agents should be considered in patients with life-threatening GI bleeding. For VKA patients presenting with an international normalized ratio > 2.5, guidelines recommend PCCs (specifically 4F-PCC), as they may exhibit greater efficacy/safety compared with fresh frozen plasma in reversal of VKA-associated GI bleeding. For DOAC patients, most guidelines recommend targeted specific reversal agents in the setting of GI bleeding; however, PCCs (primarily 4F-PCC) are often listed as another option. Resumption of anticoagulant therapy following cessation of GI bleeding is also recommended to reduce risks of future thromboembolic complications.

CONCLUSIONS

The utility of anticoagulant reversal agents in GI bleeding is recognized in guidelines; however, such agents should be reserved for use in truly life-threatening scenarios.

High-dose versus low-dose 4-factor prothrombin complex concentrate for factor Xa inhibitor reversal in intracranial hemorrhage

BACKGROUND & PURPOSE

4-factor prothrombin complex concentrate (4FPCC) is used off-label for factor Xa (FXa) inhibitor-associated intracranial hemorrhage (ICH). Guideline recommendations provide various 4FPCC dosing regimens for FXa inhibitor reversal in this setting. We evaluated 4FPCC weight-based dosing and outcomes in FXa inhibitor-associated ICH.

METHODS

We conducted a multi-center, retrospective, cohort study of ICH patients between July 2017 and February 2020. Patients were greater than 18 years of age, received 4FPCC, and were taking apixaban, rivaroxaban, or edoxaban. Patients were separated into high- (≥35 units/kg) or low-dose (<35 units/kg) 4FPCC groups. The primary outcome was hemostasis achievement. Secondary outcomes included in-hospital mortality, intensive care unit and hospital length of stay, discharge disposition, and thrombotic events. Outcomes were evaluated with binary logistic regression.

RESULTS

Of 390 patients identified, 89 were included with 74 and 15 in the high- vs low-dose groups, respectively. Mean (SD) age was 76.6 (±10.8) years. Most were taking a FXa inhibitor for atrial fibrillation (76.4%) and apixaban was the most common FXa inhibitor (65.2%). Hemostasis achievement was greater in the high- vs low-dose group (89.2% vs 46.7%; OR 11.2; 95% CI 2.4-52.6, P = 0.002). Thrombotic events were 8.2% and 6.7% in the high vs low-dose groups, respectively (OR 0.8; 95% CI 0.08-8.2, P = 0.87). No statistically significant differences were found in secondary outcomes.

CONCLUSION

In patients with FXa inhibitor-associated ICH, high-dose 4FPCC was associated with increased odds of hemostasis achievement. There was no difference in thrombotic events.

The use of direct oral anticoagulants for thromboprophylaxis or treatment of cancer-associated venous thromboembolism: a meta-analysis and review of the guidelines

BACKGROUND

Venous thromboembolism (VTE) is a common complication among patients with cancer and is one of the most common causes of increased morbidity and mortality. The use of direct oral anticoagulants (DOACs) for thromboprophylaxis and treatment of cancer-associated venous thromboembolism (CA-VTE) has been evaluated in several randomized clinical trials (RCTs). The aim of this meta-analysis was to assess efficacy and safety of using DOACs for thromboprophylaxis and treatment of CA-VTE and provide a summary for available guidelines' recommendations.

METHODS

MEDLINE was searched to identify studies evaluating the use of DOACs for thromboprophylaxis or treatment in patients with cancer. Search was limited to peer-reviewed studies published in English. Studies were excluded if they were not RCTs or subgroup analyses of data derived from RCTs, if they did not report efficacy and safety data on patients with active cancer, or if they were published as an abstract. New VTE or VTE recurrence, and major or clinically relevant non-major bleeding (CRNMB) were used to assess the efficacy and safety, respectively. The Mantel-Haenszel random-effects model risk ratios (RRs) and the corresponding 95% confidence intervals (CIs) were calculated to estimate the pooled treatment effects of DOACs.

RESULTS

Four studies evaluating DOACs use for thromboprophylaxis and four - for treatment of CA-VTE were included. Thromboprophylaxis with DOACs was associated with a significant reduction in the risk of symptomatic VTE (RR = 0.58; 95%CI 0.37,0.91) but with an incremental risk of major bleeding or CRNMB (RR = 1.57; 95%CI 1.10,2.26). CA-VTE treatment with DOACs was linked with a significant reduction in VTE recurrence (RR = 0.62; 95%CI 0.44,0.87) but with an incremental risk of CRNMB (RR = 1.58; 95%CI 1.11,2.24).

CONCLUSIONS

The DOACs are associated with a lower risk of symptomatic VTE and VTE recurrence, but the risk of bleeding remains a considerable concern. Clinical decisions should be made by assessing individual patient's risk of VTE and bleeding.

A drug utilization study of oral anticoagulants in five representative cities of China between 2015 and 2019

WHAT IS KNOWN AND OBJECTIVE

Oral anticoagulants (OACs), including warfarin and newer direct-acting OACs (DOACs), have been used for decades to prevent thromboembolic diseases. A drug utilization study was performed to determine the prescribing patterns of OACs.

METHODS

Data were extracted from the Cooperation Project of Hospital Prescription Analysis in China. A total of 455,490 prescription records from 43 tertiary hospitals in five cities of China (Beijing, Shanghai, Guangzhou, Hangzhou and Chengdu) were selected for inclusion. Quarterly trends of defined daily doses (DDDs) and defined daily dose cost (DDDC) from 1 January 2015 to 31 December 2019 were calculated.

RESULTS AND DISCUSSION

Warfarin was the most widely used OAC with DDDs between 189,982 and 176,323 from the first quarter (Q1) of 2015 to the fourth quarter (Q4) of 2019, whereas the use of DOACs increased rapidly during this period. DDDs of rivaroxaban increased from 5409 in Q1 of 2015 to 125,800 in Q4 of 2019, whereas the DDDC declined from 160.5 to 45.7. From Q1 of 2018, rivaroxaban became the most prescribed OAC, surpassing warfarin, in patients diagnosed with deep vein thrombosis. In addition, the DDDs of rivaroxaban exceeded those of warfarin in patients diagnosed with non-valvular atrial fibrillation since the second quarter (Q2) of 2019. DDDs in outpatients and inpatients increased by 80.6% and 71.4%, respectively, and the DDDC for outpatients in Q4 of 2019 was 6.7-fold higher than that in Q1 of 2015. Among patients of all ages, the DDDs in elderly patients increased from 36.8% in Q1 of 2015 to 59.4% in Q4 of 2019. Moreover, the departments of cardiology and cardiothoracic surgery prescribed the majority of the OACs.

WHAT IS NEW AND CONCLUSION

In this study, we describe OAC prescription patterns in China. DOACs, especially rivaroxaban, contribute to the continuous increase in the use of OACs. In the investigated population of China, outpatients and elderly patients were observed to be administered the highest proportion of DOACs.

Prediction of Major Bleeding in Anticoagulated Patients for Venous Thromboembolism: Comparison of the RIETE and the VTE-BLEED Scores

The performance of validated bleeding risk scores in patients with venous thromboembolism (VTE) could be different depending on the time after index event or the site of bleeding. In this study we compared the "classic" Registro Informatizado de Enfermedad TromboEmbólica (RIETE) score and the more recently developed VTE-BLEED score for the prediction of major bleeding in patients under anticoagulant therapy in different time intervals after VTE diagnosis. Out of 82,239 patients with acute VTE, the proportion of high-risk patients according to the RIETE and VTE-BLEED scores was 7.1 and 62.3%, respectively. The performance of both scores across the different study periods (first 30 days after VTE diagnosis, days 31-90, days 91-180, and days 181-360) was similar, with areas under the receiving operating characteristics (ROC) curve (AUC) ranging between 0.69 and 0.72. However, the positive predictive values were low, ranging between 0.6 and 3.9 (better for early major bleeding than for later periods). A sensitivity analysis limited to patients with unprovoked VTE showed comparable results. Both scores showed a trend toward a better prediction of extracranial than intracranial major bleeding, the RIETE score resulting more useful for early extracranial bleeding and the VTE-BLEED for late intracranial hemorrhages. Our study reveals that the usefulness of available bleeding scores may vary depending on the characteristics of the patient population and the time frame evaluated. Dynamic scores could be more useful for this purpose.

A taxonomy and framework for identifying and developing actionable statements in guidelines suggests avoiding informal recommendations

OBJECTIVE

To propose a taxonomy and framework that identifies and presents actionable statements in guidelines.

STUDY DESIGN AND SETTING

We took an iterative approach reviewing case studies of guidelines produced by the World Health Organization and the American Society of Hematology to develop an initial conceptual framework. We then tested it using randomly selected recommendations from published guidelines addressing COVID-19 from different organizations, evaluated its results, and refined it before retesting. The urgency and availability of evidence for development of these recommendations varied. We consulted with experts in research methodology and guideline developers to improve the final framework.

RESULTS

The resulting taxonomy and framework distinguishes five types of actional statements: formal recommendations; research recommendations; good practice statements; implementation considerations, tools and tips; and informal recommendations. These statements should respond to a priori established criteria and require a clear structure and recognizable presentation in a guideline. Most importantly, this framework identifies informal recommendations that differ from formal recommendations by how they consider evidence and in their development process.

CONCLUSION

The identification, standardization and explicit labelling of actionable statements according to the framework may support guideline developers to create actionable statements with clear intent, avoid informal recommendations and improve their understanding and implementation by users.

Retrospective Comparison of Andexanet Alfa and 4-Factor Prothrombin Complex for Reversal of Factor Xa-Inhibitor Related Bleeding

The aim of this retrospective study was to compare andexanet alfa and 4-factor prothrombin complex (4F-PCC) for reversal of factor Xa (FXa)-inhibitor bleeding. Patients that received andexanet alfa for reversal were included. An equivalent number of patients administered 4F-PCC for FXa-inhibitor bleeding were randomly selected as historical controls. The primary outcome was effective hemostasis achievement within 12 h, defined using ANNEXA-4 criteria. Thromboembolic events and mortality within 30 days were also evaluated. A total of 32 patients were included. Baseline characteristics were not statistically different between andexanet alfa (n = 16) and 4F-PCC (n = 16). Intracranial bleeding was the primary reversal indication in 43.8% versus 62.5% of patients, respectively. Effective hemostasis was reached in 75.0% of andexanet alfa patients compared to 62.5% of 4F-PCC patients (P = .70). Thromboembolic events occurred in 4 (25.0%) patients and 3 (18.8%) patients, respectively (P = .99). Mortality incidence was 12.5% and 31.3%, respectively (P = .39). Andexanet alfa and 4F-PCC attained hemostasis in a majority of patients. A high, but a similar rate of thromboembolic events was seen with both treatments. Prospective studies are needed to elucidate comparative risks and benefits of the 2 agents.

Fixed Versus Variable Dosing of Prothrombin Complex Concentrate for Bleeding Complications of Vitamin K Antagonists-The PROPER3 Randomized Clinical Trial

STUDY OBJECTIVE

To determine if a fixed dose of 1000 IU of 4-factor prothrombin complex concentrate (4F-PCC) is as effective as traditional variable dosing based on body weight and international normalized ratio (INR) for reversal of vitamin K antagonist (VKA) anticoagulation.

METHODS

In this open-label, multicenter, randomized clinical trial, patients with nonintracranial bleeds requiring VKA reversal with 4F-PCC were allocated to either a 1,000-IU fixed dose of 4F-PCC or the variable dose. The primary outcome was the proportion of patients with effective hemostasis according to the International Society of Thrombosis and Haemostasis definition. The design was noninferiority with a lower 95% confidence interval of no more than -6%. When estimating sample size, we assumed that fixed dosing would be 4% superior.

RESULTS

From October 2015 until January 2020, 199 of 310 intended patients were included before study termination due to decreasing enrollment rates. Of the 199 patients, 159 were allowed in the per-protocol analysis. Effective hemostasis was achieved in 87.3% (n=69 of 79) in fixed compared to 89.9% (n=71 of 79) in the variable dosing cohort (risk difference 2.5%, 95% confidence interval -13.3 to 7.9%, P=.27). Median door-to-needle times were 109 minutes (range 16 to 796) in fixed and 142 (17 to 1076) for the variable dose (P=.027). INR less than 2.0 at 60 minutes after 4F-PCC infusion was reached in 91.2% versus 91.7% (P=1.0).

CONCLUSION

The large majority of patients had good clinical outcome after 4F-PCC use; however, noninferiority of the fixed dose could not be demonstrated because the design assumed the fixed dose would be 4% superior. Door-to-needle time was shortened with the fixed dose, and INR reduction was similar in both dosing regimens.

How to write a guideline: a proposal for a manuscript template that supports the creation of trustworthy guidelines

Trustworthy health guidelines should provide recommendations, document the development process, and highlight implementation information. Our objective was to develop a guideline manuscript template to help authors write a complete and useful report. The McMaster Grading of Recommendations Assessment, Development and Evaluation (GRADE) centre collaborated with the American Society of Hematology (ASH) to develop guidelines for the management of venous thromboembolism. A template for reporting the guidelines was developed based on prior approaches and refined using input from other key stakeholders. The proposed guideline manuscript template includes: 1) title for guideline identification; 2) abstract, including a summary of key recommendations; 3) overview of all recommendations [executive summary]; 4) the main text, providing sufficient detail on the entire process including objectives, background, and methodological decisions from panel selection and conflict of interest management to criteria for updating, as well as supporting information such as links to online (interactive) tables. The template further allows for tailoring to the specific topic, using examples. Initial experience with the ASH guideline manuscript template was positive, and challenges included drafting descriptions of recommendations involving multiple management pathways, tailoring the template for a specific guideline, and choosing key recommendations to highlight. Feedback from a larger group of guideline authors and users will be needed to evaluate its usefulness and refine. The proposed guideline manuscript template is the first detailed template for transparent and complete reporting of guidelines. Consistent application of the template may simplify preparing an evidence-based guideline manuscript and facilitate its use.

Rates of rebleeding, thrombosis and mortality associated with resumption of anticoagulant therapy after anticoagulant-related bleeding

BACKGROUND:

Data on resuming oral anticoagulants (OACs) after bleeding are primarily from studies involving patients given warfarin, with few data on direct OACs (DOACs). We aimed to characterize prescribing patterns for OACs after OAC-related bleeding and compare the rates of bleeding, thrombosis and mortality in patients who resumed either type of OAC with those who did not.

METHODS:

We conducted a population-based cohort study of adults aged 66 years or older who were admitted to hospital for bleeding while receiving OACs from Apr. 1, 2012, to Mar. 31, 2017, using linked administrative health databases from Ontario. We used competing risk methods to calculate cause-specific adjusted hazard ratios (HRs) for thrombosis, bleeding and mortality with resumption of OACs adjusted as a time-varying covariate. We determined time to OAC resumption using the Kaplan–Meier method.

RESULTS:

We included 6793 patients with gastrointestinal (n = 4297, 63.3%), intracranial (n = 805, 11.9%) or other bleeding (n = 1691, 25.0%). At cohort entry, 3874 patients (57.0%) were prescribed warfarin and 2919 patients (43.0%) were prescribed a DOAC. The most common indication for OAC was atrial fibrillation (n = 5557, 81.8%), followed by venous thromboembolism (n = 1367, 20.1%). Oral anticoagulants were resumed in 4792 patients (70.5%) within 365 days of the index bleed. The median time to resumption was 46 (interquartile range 6–550) days. We found that resuming OAC was associated with reduced rates of thrombosis (adjusted HR 0.60, 95% confidence interval [CI] 0.50–0.72) and mortality (adjusted HR 0.54, 95% CI 0.48–0.60), and an increased rate of rebleeding (adjusted HR 1.88, 95% CI 1.64–2.17).

INTERPRETATION:

We found that resuming OAC is associated with a reduction in thrombosis and mortality but an increase in bleeding. Randomized controlled trials that evaluate the net benefit of strategies for resumption of OAC after a bleeding event are warranted.

Drive-through Anticoagulation Clinic During The COVID-19 Pandemic

An innovative approach to anticoagulation management during the COVID-19 pandemic was used at our center that allowed patients to stay in their vehicle while our anticoagulation advanced practice registered nurse obtained blood for point-of-care international normalized ratio (INR) testing while education and counseling were completed. A significant improvement in the median percentage of INR within the therapeutic range was observed among the patients who used the drive-through clinic. A small group of patients improved compliance to anticoagulation monitoring. Clinical care models, such as this clinic approach may improve patient compliance and adherence to anticoagulation beyond the pandemic needs.

Thrombophilia testing in the era of direct oral anticoagulants

Venous thromboembolism (VTE) is increasingly recognised in primary and secondary care practice. The arrival of direct oral anticoagulants (DOACs) has made the management of VTE easier and more convenient. Some patients established on DOACs may need screening for underlying thrombophilias as certain thrombophilic conditions are known to confer a higher thrombosis risk, although the guidelines for when and how to test for a thrombophilia, especially in a patient taking a DOAC, are unclear. This literature review aims to examine when thrombophilia screening should take place in a patient already taking a DOAC, the effect of DOACs on thrombophilia tests, and analyse whether DOACs are safe and effective in both inherited and acquired thrombophilias.

Effectiveness and Safety of Twice- Versus Thrice-Daily Subcutaneous Heparin for Venous Thromboembolism Prophylaxis at a Large Academic Medical Center

BACKGROUND

Dosing variation of subcutaneous unfractionated heparin (UFH) exist for venous thromboembolism prophylaxis (VTEP).

OBJECTIVE

The purpose of this study was to compare the safety and effectiveness of thrice-daily (TID) versus twice-daily (BID) administration of UFH during a heparin shortage for VTEP.

METHODS

A single-center retrospective analysis was conducted in patients with orders for BID subcutaneous UFH during a heparin shortage from September 1, 2019, to February 4, 2020. These patients were matched to patients with TID subcutaneous UFH orders from January 1, 2019, to May 31, 2019. The primary outcome was the incidence of deep-vein thrombosis or pulmonary embolism confirmed by imaging during hospitalization. The secondary outcome was the incidence of major or clinically relevant nonmajor bleeding events as defined by International Society on Thrombosis and Haemostasis (ISTH) definitions.

RESULTS

A total of 277 patients with orders for BID UFH and meeting inclusion criteria were evaluated and matched to patients who received TID UFH. After the exclusion criteria were implemented, 510 patients remained in the TID group. The primary outcome occurred in 4% of patients in the BID group and 3% in the TID group (P = 0.645). Major bleeding or clinically relevant nonmajor bleeding events occurred in 10% of patients in the BID group and 8% in the TID group (P = 0.310).

CONCLUSION AND RELEVANCE

There was no difference in effectiveness or safety of TID versus BID subcutaneous UFH for VTEP. During a heparin shortage, transitioning patients to BID UFH for VTEP to conserve supply may be considered.

Analysis of Direct Oral Anticoagulant Therapy With Concomitant Use of Interacting Antiretroviral Agents

Background: A theoretical interaction exists between human immunodeficiency virus (HIV) antiretroviral (ARV) agents and direct oral anticoagulants (DOACs), although the clinical significance is unclear. Objective: This study aimed to assess characteristics, prescribing patterns, and outcomes associated with concomitant therapy. Methods: A single-center, retrospective review was performed on patients older than 18 years prescribed a DOAC for any indication with concurrent interacting ARV(s) from June 2016 through June 2019. The primary endpoint was to assess prescribing and population characteristics. Secondary endpoints were to evaluate safety outcomes, DOAC level monitoring, readmissions, outpatient follow-up, and DOAC modification interventions. Results: Thirty-six patients (72 hospital admissions) were identified. The most common DOAC was apixaban (83.3%) and ARV was ritonavir (50%). Of the 72 encounters, 26 (36.1%) DOACs were dosed appropriately per guideline recommendations. Twenty pharmacy interventions for therapy modification were recognized. Eleven (30.6%) patients experienced bleeding and 2 (5.6%) thrombosis. Of the adverse events, all patients had renal impairment. Conclusions: As DOAC utilization grows, increasing use in HIV could be expected. More frequent adjustment or avoidance is recommended per guidelines. Our data suggest the majority of patients receive CYP3A4-inhibiting regimens. Caution should be employed with renal insufficiencies. Further studies are warranted to assess safety and efficacy within this population.

Methodology for adaptation of the ASH Guidelines for Management of Venous Thromboembolism for the Latin American context

BACKGROUND

From 2017 to 2020, the American Society of Hematology (ASH) collaborated with 12 hematology societies in Latin America to adapt the ASH guidelines on venous thromboembolism (VTE).

OBJECTIVE

To describe the methods used to adapt the ASH guidelines on venous thromboembolism.

METHODS

Each society nominated 1 individual to serve on the guideline panel. The work of the panel was facilitated by the 2 methodologists. The methods team selected 4 of the original VTE guidelines for a first round. To select the most relevant questions, a 2-step prioritization process was conducted through an on-line survey and then through in-person discussion. During an in-person meeting in Rio de Janeiro, Brazil, from 23 April through 26 April 2018, the panel developed recommendations using the ADOLOPMENT approach. Evidence about health effects from the original guidelines was reused, but important data about resource use, accessibility, feasibility, and impact in health equity were added.

RESULTS

In the guideline accompanying this paper, Latin American panelists selected 17 questions from an original pool of 49. Of the 17 questions addressed, substantial changes were introduced for 5 recommendations, and remarks were added or modified for 12 recommendations.

CONCLUSIONS

By using the evidence from an international guideline, a significant amount of work and time were saved; by adding regional evidence, the final recommendations were tailored to the Latin American context. This experience offers an alternative to develop guidelines relevant to local contexts through a global collaboration.

ASH, ABHH, ACHO, Grupo CAHT, Grupo CLAHT, SAH, SBHH, SHU, SOCHIHEM, SOMETH, Sociedad Panameña de Hematología, SPH, and SVH 2021 guidelines for management of venous thromboembolism in Latin America

BACKGROUND

Venous thromboembolism (VTE) is a common disease in Latin American settings. Implementing international guidelinn Aes in Latimerican settings requires additional considerations.

OBJECTIVE

The purpose of our study was to provide evidence-based guidelines about managing VTE for Latin American patients, clinicians, and decision makers.

METHODS

We used the Grading of Recommendations, Assessment, Development and Evaluation (GRADE)-ADOLOPMENT method to adapt recommendations from 2 American Society of Hematology (ASH) VTE guidelines (Treatment of VTE and Anticoagulation Therapy). ASH and local hematology societies formed a guideline panel comprised of medical professionals from 10 countries in Latin America. Panelists prioritized 18 questions relevant for the Latin American context. A knowledge synthesis team updated evidence reviews of health effects conducted for the original ASH guidelines and summarized information about factors specific to the Latin American context (ie, values and preferences, resources, accessibility, feasibility, and impact on health equity).

RESULTS

The panel agreed on 17 recommendations. Compared with the original guideline, 4 recommendations changed direction and 1 changed strength.

CONCLUSIONS

This guideline adolopment project highlighted the importance of contextualization of recommendations suggested by the changes to the original recommendations. The panel also identified 2 implementation priorities for the region: expanding the availability of home treatment and increasing the availability of direct oral anticoagulants (DOACs). The guideline panel made a conditional recommendation in favor of home treatment for individuals with deep venous thrombosis and a conditional recommendation for either home or hospital treatment for individuals with pulmonary embolism. In addition, a conditional recommendation was made in favor of DOACs over vitamin K antagonists for several populations.

Derivation and validation of predictors of oral anticoagulant-related adverse events in seniors transitioning from hospital to home

INTRODUCTION

Oral anticoagulant (OAC)-related adverse events are high post-hospitalization. We planned to develop and validate a prediction model for OAC-related harm within 30 days of hospitalization.

METHODS

We undertook a population-based study of adults aged ≥66 years who were discharged from hospital on an OAC from September 2010 to March 2015 in Ontario, Canada. The primary outcome was a composite of time to first hospitalization or emergency department visit for a hemorrhagic or thromboembolic event, or mortality within 30 days of hospital discharge. Cox proportional hazards regression was used to build the model.

RESULTS

We included 120,721 patients of which 5423 experienced the outcome. Most patients were aged ≥75 years (59.5%) and were female (55.6%). Sixty percent of the cohort had a follow-up visit with a healthcare provider within 7 days of discharge. Patients discharged on a direct acting OAC versus warfarin (apixaban: Hazard Ratio [HR] 0.82, 95% confidence interval [CI] 0.71-0.94; dabigatran: HR 0.73, 95% CI 0.63-0.84; rivaroxaban: HR 0.79, 95% CI 0.71-0.88), were prevalent users of the dispensed OAC versus incident users (HR 0.82, 95% CI 0.69-0.96), had a joint replacement in the past 35 days (HR 0.40, 95% CI 0.33-0.50) or major surgery during index hospital stay (HR 0.69, 95% CI 0.60-0.80) had a lower risk for the outcome. The Cox model was stable with acceptable discrimination but poor goodness-of-fit.

CONCLUSIONS

A model for OAC-related harm in the early post-discharge period was developed. External validation studies are required to understand the model's poor calibration.

Antithrombotic Therapy for VTE Disease: Second Update of the CHEST Guideline and Expert Panel Report - Executive Summary

BACKGROUND

This is the second update to the 9^th edition of these guidelines. We provide recommendations on 17 PICO (Patients, Interventions, Comparators, Outcomes) questions, four of which have not been addressed previously.

METHODS

We generate strong and weak recommendations based on high, moderate, and low-certainty evidence, using GRADE methodology.

RESULTS

The panel generated 29 guidance statements, 13 of which are graded as strong recommendations, covering aspects of antithrombotic management of venous thromboembolism from initial management through secondary prevention and risk reduction of post-thrombotic syndrome. Four new guidance statements are added that did not appear in the 9^th edition (2012) or first update (2016). Eight statements have been substantially modified from the first update.

CONCLUSION

New evidence has emerged since 2016 which further informs the standard of care for patients with venous thromboembolism. Substantial uncertainty remains regarding important management questions, particularly in limited disease and special patient populations.

The emergency department evaluation and management of massive hemoptysis

INTRODUCTION

Massive hemoptysis is a life-threatening emergency that requires rapid evaluation and management. Recognition of this deadly condition, knowledge of the initial resuscitation and diagnostic evaluation, and communication with consultants capable of definitive management are key to successful treatment.

OBJECTIVE

The objective of this narrative review is to provide an evidence-based review on the management of massive hemoptysis for the emergency clinician.

DISCUSSION

Rapid diagnosis and management of life-threatening hemoptysis is key to patient survival. The majority of cases arise from the bronchial arterial system, which is under systemic blood pressure. Initial management includes patient and airway stabilization, reversal of coagulopathy, and identification of the source of bleeding using computed tomography angiogram. Bronchial artery embolization with interventional radiology has become the mainstay of treatment; however, unstable patients may require advanced bronchoscopic procedures to treat or temporize while additional information and treatment can be directed at the underlying pathology.

CONCLUSION

Massive hemoptysis is a life-threatening condition that emergency clinicians must be prepared to manage. Emergency clinicians should focus their management on immediate resuscitation, airway preservation often including intubation and isolation of the non-bleeding lung, and coordination of definitive management with available consultants including interventional radiology, interventional pulmonology, and thoracic surgery.

Side-Effects of COVID-19 on Patient Care: An INR Story

Background

Numerous studies have documented reduced access to patient care due to the COVID-19 pandemic including access to a diagnostic or screening tests, prescription medications, and treatment for an ongoing condition. In the context of clinical management for venous thromboembolism, this could result in suboptimal therapy with warfarin. We aimed to determine the impact of the pandemic on utilization of International normalized ratio (INR) testing and the percentage of high and low results.

Methods

INR data from 11 institutions were extracted to compare testing volume and the percentage of INR results ≥3.5 and ≤1.5 between a pre-pandemic period (January-June 2019, period 1) and a portion of the COVID-19 pandemic period (January-June 2020, period 2). The analysis was performed for inpatient and outpatient cohorts.

Results

Testing volumes showed relatively little change in January and February, followed by a significant decrease in March, April and May, and then returned to baseline in June. Outpatient testing showed a larger percentage decrease in testing volume compared to inpatient testing. At 10 of the 11 study sites we observed an increase in the percentage of abnormal high INR results as test volumes decreased, primarily among outpatients.

Conclusion

The COVID-19 pandemic impacted INR testing among outpatients which may be attributable to several factors. Increased supratherapeutic INR results during the pandemic period when there was reduced laboratory utilization and access to care is concerning because of the risk of adverse bleeding events in this group of patients. This could be mitigated in the future by offering drive through testing and/or widespread implementation of home INR monitoring.

A Retrospective Review of Four-Factor Prothrombin Complex Concentrate for Factor Xa Inhibitor-Related Bleedings

BACKGROUND

The use of factor Xa inhibitors has grown in popularity; however, the risk of major bleeding events requires for the appropriate reversal agent. The recent approved agent for factor Xa inhibitor reversal, andexanet alfa, has limited clinical efficacy and safety data, and it can be a financial burden on healthcare systems due to its high cost. Four-factor prothrombin complex concentrate (4F-PCC) has been utilized off label in patients with factor Xa inhibitor-related bleedings. Objective: The aim of this study was to assess the safety and efficacy of 4F-PCC in managing factor Xa inhibitor-related bleedings.

METHODS

This is an observational, retrospective review of 4F-PCC usage in treating factor Xa inhibitor-related bleeds from May 2014 to December 2018 at a single health system. Efficacy was evaluated using the assessment criteria described by Sarode et al. Secondary outcomes analyzed included thromboembolic events, length of stay, mortality, and discharge disposition.

RESULTS

Fifty-nine patient charts were reviewed, and 48 patients were included in the study analysis. The administration of 4F-PCC achieved effective hemostasis in 33 patients (68%), and effective hemostasis was achieved in 12 patients (86%) who had intracranial hemorrhage and did not receive any surgical intervention. Thromboembolic events occurred in 4 patients within 30 days from 4F-PCC use. A majority of patients (85.4%) were discharged from the hospital to home or long-term care; 7 patients (14.6%) expired in the hospital.

CONCLUSION

Efficacy was achieved in over half of the patient population in this cohort who received 4F-PCC for factor Xa inhibitor-related bleeding events.

Fixed-dose prothrombin complex concentrate for emergent warfarin reversal among patients with intracranial hemorrhage

INTRODUCTION

Four-factor prothrombin complex concentrate (4PCC) is the preferred reversal agent for warfarin reversal, although the ideal dose is unknown. Fixed-dose 4PCC offers simplified dosing compared to standard-dosing algorithms with potentially lower risks of thromboembolic complications given lower doses are typically utilized.

METHODS

Retrospective, observational, multicentered, pre- post- study of patients who received 4PCC for warfarin reversal among four hospitals within the same regional health system. Standard-dose patients received variable doses ranging from 25 to 50 units/kg based on total body weight and initial INR and fixed-dose patients received 2000 units. The primary outcome was achievement of a target INR ≤ 1.4 on the first post-4PCC INR result.

RESULTS

After exclusions, 48 and 42 patients were analyzed in the standard-dose and fixed-dose groups, respectively. There was no difference in the ability to achieve a target INR of ≤1.4 (82.6% vs 81.5%, p = 0.14). Both groups received the same median dose of 2000 units, although fixed-dose patients actually received a higher weight-based dose than standard-dose patients (27 units/kg vs 24.5 units/kg).

CONCLUSION

A fixed-dose 4PCC regimen of 2000 units among patients with ICH was as effective as standard-dose 4PCC for INR reversal among patients with ICH. However, fixed-doses of 2000 units at times exceeded standard 4PCC doses which may be contradictory to the goals of fixed-dose 4PCC for warfarin reversal.