Longitudinal assessment of coagulation potential before, during, and following an in vitro fertilization cycle.

INTRODUCTION: The association between estrogen and hypercoagulability is well-established but little is known about coagulation dynamics during IVF. Our goal was to measure coagulation potential prior to, during, and following an IVF cycle and to investigate differences by conception outcome. MATERIALS AND METHODS: Patients undergoing IVF with fresh embryo transfer at a single academic center using oral contraceptive pills for cycle batching underwent evaluation of thrombin generation using the calibrated automated thrombogram at multiple points during the IVF cycle. Multiple thrombin generation parameters were compared across timepoints and by IVF cycle outcome using ANOVA repeated measures analysis. RESULTS: Of the 17 patients included, 11 conceived. There was a significant increase in peak and total thrombin generation in the entire cohort between the pre-treatment natural follicular phase and following a short course of oral contraceptive pills used for cycle batching. Further increase in these parameters was seen at the time of oocyte retrieval. In the pre-treatment natural follicular phase, patients who conceived had lower peak thrombin generation. There were changes throughout the cycle for factors II, V, VIII, X, XI, XII, antithrombin, and tissue factor pathway inhibitor. Only Factor XI was distinguishable by conception status; values were lower at all visits in patients who conceived. CONCLUSION: Increases in coagulation potential are seen in patients undergoing IVF following a short course of oral contraceptive pills for cycle batching and continue during controlled ovarian hyperstimulation. Those who conceived were seen to have lower peak thrombin generation in the pre-treatment natural follicular phase.

Clopidogrel-herb Interactions: A Pharmacokinetic and Pharmacodynamic Assessment in a Rat Model.

BACKGROUND: Herbs usually contain a mixture of biologically active constituents, which can interact with numerous prescribed drugs and alter their safety profiles. OBJECTIVES: The current investigation was aimed to evaluate the effect of commonly used herbal products including black seed (Nigella sativa), garden cress (Lepidium sativum), and fenugreek (Trigonella foenum-graecum) on the pharmacokinetics and pharmacodynamics of clopidogrel using a Wistar rat model. METHODS: A GC-MS analysis revealed the presence of several phytoconstitutents (polyphenols) in the extracts of black seed, garden cress, and fenugreek. These polyphenols have the potential to interfere with clopidogrel effect. Plasma concentrations of clopidogrel were measured at different time points in the absence and presence of the concurrent use of tested herbal products and the pharmacokinetic parameters were calculated. Bleeding time was measured in various groups as a measure of the antiplatelet effect of clopidogrel. RESULTS: Area under the plasma concentration-time curves (AUC0-∞) of clopidogrel were 35.53 ±0.89 µg/ml*h (p<0.05), 26.01 ±0.90 µg/ml*h (p>0.05) and 32.80 ±2.51 µg/ml*h (p<0.05) in the black seed, garden cress and fenugreek group, respectively, compared with that of the control group (27.02 ±0.42 µg/ml*h). Treatment with black seed also caused an increase in clopidogrel Cmax by 31.52% (p<0.05) and with fenugreek by 21.42% (p<0.05); Cmax, did not changed with garden cress treatment (6.48 ±0.15 µg/ml versus 6.12 ±0.21 µg/ml, p>0.05). The pharmacodynamic evaluation of the antiplatelet effect of clopidogrel in the presence of herbal products treatment showed a significant prolongation in the bleeding time from a control baseline by ~22-26%, and by added ~8-12% in reference to clopidogrel therapeutic effect (p<0.05). CONCLUSION: The concurrent use of black seed, fenugreek, or garden cress can alter the pharmacokinetics and pharmacodynamics of clopidogrel to varying degrees due to the presence of various bioactive polyphenols. This is probably due to changes in drug disposition and its antiplatelet action. Further confirmation can determine the clinical relevance of these observations and identify the exact constituents responsible for such activities.

OpenSAFELY: impact of national guidance on switching anticoagulant therapy during COVID-19 pandemic.

BACKGROUND: Early in the COVID-19 pandemic, the National Health Service (NHS) recommended that appropriate patients anticoagulated with warfarin should be switched to direct-acting oral anticoagulants (DOACs), requiring less frequent blood testing. Subsequently, a national safety alert was issued regarding patients being inappropriately coprescribed two anticoagulants following a medication change and associated monitoring. OBJECTIVE: To describe which people were switched from warfarin to DOACs; identify potentially unsafe coprescribing of anticoagulants; and assess whether abnormal clotting results have become more frequent during the pandemic. METHODS: With the approval of NHS England, we conducted a cohort study using routine clinical data from 24 million NHS patients in England. RESULTS: 20 000 of 164 000 warfarin patients (12.2%) switched to DOACs between March and May 2020, most commonly to edoxaban and apixaban. Factors associated with switching included: older age, recent renal function test, higher number of recent INR tests recorded, atrial fibrillation diagnosis and care home residency. There was a sharp rise in coprescribing of warfarin and DOACs from typically 50-100 per month to 246 in April 2020, 0.06% of all people receiving a DOAC or warfarin. International normalised ratio (INR) testing fell by 14% to 506.8 patients tested per 1000 warfarin patients each month. We observed a very small increase in elevated INRs (n=470) during April compared with January (n=420). CONCLUSIONS: Increased switching of anticoagulants from warfarin to DOACs was observed at the outset of the COVID-19 pandemic in England following national guidance. There was a small but substantial number of people coprescribed warfarin and DOACs during this period. Despite a national safety alert on the issue, a widespread rise in elevated INR test results was not found. Primary care has responded rapidly to changes in patient care during the COVID-19 pandemic.

Ex Vivo Assessment of Different Oral Anticoagulant Regimens on Pump Thrombosis in a HeartWare Ventricular Assist Device.

BACKGROUND: In light of decreased intracranial hemorrhage with direct oral anticoagulants and concerns about their safety in continuous flow left ventricular assist devices, we conducted an ex vivo study of thrombus formation using multiple anticoagulation agents. METHODS: A continuous flow left ventricular assist device (HeartWare ventricular assist device) hemocompatibility loop was run using human blood under 7 conditions: control (no anticoagulation or antiplatelet); in vitro addition of aspirin; in vitro addition of apixaban at low dose (equivalent 2.5 mg twice daily); addition of apixaban at high dose (equivalent 5 mg twice daily); patients on warfarin; patients on apixaban (5 mg twice daily); and patients on dabigatran (150 mg twice daily). The primary outcome was time to formation of intrapump thrombosis. Secondary outcomes were reduction in clotting times over 1 hour, hemolysis, reduced platelet aggregation, and von Willebrand activity. RESULTS: Twenty-one runs were completed. Times to thrombosis in median (interquartile range) were control, 131 (127-134.5); in vitro aspirin, 124 (114.5-137); and patients on dabigatran, 131 (130.5-135.5) minutes, respectively. Times in patients on warfarin were, 137 (136.5-143.5); in vitro low-dose apixaban, 141 (138.5-142); and patients on apixaban, 140 (138-142.5) minutes, respectively. No thrombus formed in the in vitro high-dose apixaban group. There were no significant differences between the individual groups. When all apixaban groups were compared with nonapixaban groups, the time to thrombosis formation was significantly longer, 143 (137-150) versus 133.5 (128.5-140) minutes, P=0.02. There were similar changes in lactate dehydrogenase levels and other secondary end points. CONCLUSIONS: In an in vitro study of anticoagulation using human blood in a mock loop with a HeartWare HVAD, we demonstrated similar thrombosis times for apixaban and warfarin. Time to clotting was longer in the combined apixaban groups compared with combined other groups, but thrombosis times between individual groups were not significantly different.

In vitro assessment and phase I randomized clinical trial of anfibatide a snake venom derived anti-thrombotic agent targeting human platelet GPIbα.

The interaction of platelet GPIbα with von Willebrand factor (VWF) is essential to initiate platelet adhesion and thrombosis, particularly under high shear stress conditions. However, no drug targeting GPIbα has been developed for clinical practice. Here we characterized anfibatide, a GPIbα antagonist purified from snake (Deinagkistrodon acutus) venom, and evaluated its interaction with GPIbα by surface plasmon resonance and in silico modeling. We demonstrated that anfibatide interferds with both VWF and thrombin binding, inhibited ristocetin/botrocetin- and low-dose thrombin-induced human platelet aggregation, and decreased thrombus volume and stability in blood flowing over collagen. In a single-center, randomized, and open-label phase I clinical trial, anfibatide was administered intravenously to 94 healthy volunteers either as a single dose bolus, or a bolus followed by a constant rate infusion of anfibatide for 24 h. Anfibatide inhibited VWF-mediated platelet aggregation without significantly altering bleeding time or coagulation. The inhibitory effects disappeared within 8 h after drug withdrawal. No thrombocytopenia or anti-anfibatide antibodies were detected, and no serious adverse events or allergic reactions were observed during the studies. Therefore, anfibatide was well-tolerated among healthy subjects. Interestingly, anfibatide exhibited pharmacologic effects in vivo at concentrations thousand-fold lower than in vitro, a phenomenon which deserves further investigation.Trial registration: Clinicaltrials.gov NCT01588132.

Examining therapeutic equivalence between branded and generic warfarin in Brazil: The WARFA crossover randomized controlled trial.

OBJECTIVES: To determine whether the generic and branded warfarins used as anticoagulants in Brazil are therapeutic equivalents based on their international normalized ratio (INR) results. METHODS: This crossover randomized controlled trial had four periods. We used the branded Marevan and two generic versions of warfarin sodium tablets, manufactured by União Química and Teuto laboratories, all purchased from retail drugstores. Eligible participants were outpatients from an anticoagulation clinic at a university hospital in São Paulo, Brazil. They had atrial fibrillation or flutter and had been using warfarin for at least 2 months with an INR therapeutic range of 2.0-3.0. Randomization was by numbered, opaque, sealed envelopes. Healthcare personnel and outcome assessors were blinded to treatments, but patients were not. The primary outcome was the variability in the INR (ΔINR) and secondary outcomes included mean INR. We accepted formulations as equivalent if the 95% confidence interval (CI) of the comparison of ΔINR between branded and generic formulations was within the limit of ±0.49. RESULTS: One hundred patients were recruited and randomized to six sequences of treatment (four sequences with n = 17 and two sequences with n = 16). União Química generic warfarin had equivalent variability in the INR to Marevan (ΔINR +0.09 [95% CI -0.29 to +0.46], n = 84). Comparison between Teuto generic warfarin and Marevan was inconclusive (ΔINR +0.29 [95% CI -0.09 to +0.68], n = 84). CONCLUSIONS: Marevan and União Química warfarin had equivalent therapeutic effectiveness and both could be confidently used for anticoagulation. The comparison between Marevan and TW was inconclusive and does not warrant a statement of equivalence. Our methods are especially important for comparing generic and branded drugs that raise concerns and may be subject of future investigations by regulatory agents. TRIAL REGISTRATION: ClinicalTrials.gov NCT02017197.

The effectiveness and value of emicizumab and valoctocogene roxaparvovec for the management of hemophilia A without inhibitors.

DISCLOSURES: Funding for this summary was contributed by Arnold Ventures, California Health Care Foundation, The Donaghue Foundation, Harvard Pilgrim Health Care, and Kaiser Foundation Health Plan to the Institute for Clinical and Economic Review (ICER), an independent organization that evaluates the evidence on the value of health care interventions. ICER's annual policy summit is supported by dues from AbbVie, Aetna, America's Health Insurance Plans, Anthem, Alnylam, AstraZeneca, Biogen, Blue Shield of CA, Boehringer-Ingelheim, Cambia Health Services, CVS, Editas, Evolve Pharmacy, Express Scripts, Genentech/Roche, GlaxoSmithKline, Harvard Pilgrim, Health Care Service Corporation, HealthFirst, Health Partners, Humana, Johnson & Johnson (Janssen), Kaiser Permanente, LEO Pharma, Mallinckrodt, Merck, Novartis, National Pharmaceutical Council, Pfizer, Premera, Prime Therapeutics, Regeneron, Sanofi, Spark Therapeutics, uniQure, and United Healthcare. Agboola, Rind, Herron-Smith, and Pearson are employed by ICER. Walton and Quach, through the University of Illinois at Chicago, received funding from ICER for development of the economic model described in this report.

High-Dose Epinephrine Enhances Platelet Aggregation at the Expense of Procoagulant Activity.

Platelet activation is characterized by shape change, granule secretion, activation of fibrinogen receptor (glycoprotein IIb/IIIa) sustaining platelet aggregation, and externalization of negatively charged aminophospholipids contributing to platelet procoagulant activity. Epinephrine (EPI) alone is a weak platelet activator. However, it is able to potentiate platelet activation initiated by other agonists. In this work, we investigated the role of EPI in the generation of procoagulant platelets. Human platelets were activated with convulxin (CVX), thrombin (THR) or protease-activated receptor (PAR) agonists, EPI, and combination thereof. Platelet aggregation was assessed by light transmission aggregometry or with PAC-1 binding by flow cytometry. Procoagulant collagen-and-THR (COAT) platelets, induced by combined activation with CVX-and-THR, were visualized by flow cytometry as Annexin-V-positive and PAC-1-negative platelets. Cytosolic calcium fluxes were monitored by flow cytometry using Fluo-3 indicator. EPI increased platelet aggregation induced by all agonist combinations tested. On the other hand, EPI dose-dependently reduced the formation of procoagulant COAT platelets generated by combined CVX-and-THR activation. We observed a decreased Annexin-V-positivity and increased binding of PAC-1 with the triple activation (CVX + THR + EPI) compared with CVX + THR. Calcium mobilization with triple activation was decreased with the higher EPI dose (1,000 µM) compared with CVX + THR calcium kinetics. In conclusion, when platelets are activated with CVX-and-THR, the addition of increasing concentrations of EPI (triple stimulation) modulates platelet response reducing cytosolic calcium mobilization, decreasing procoagulant activity, and enhancing platelet aggregation.

Pitfalls in the assessment of disseminated intravascular coagulation in patients on dabigatran.

Dabigatran is an orally administrated anticoagulant that directly inhibits thrombin. However, the drug can affect routine coagulation tests such as prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin time (TT), as well as haemostasis assays, (e.g., clot-based coagulation factor assays). There are limited data on the effect of dabigatran on some fibrinogen measurements and on D-dimer assays, both important components in the laboratory assessment of disseminated intravascular coagulation (DIC). The objectives of this study were: (1) to determine the effects of various concentrations of dabigatran on fibrinogen and D-Dimer assays; and (2) to compare the von Clauss method of fibrinogen measurement using two reagents with differing thrombin concentrations (35 UNIH/mL and 100 UNIH/mL) and PT-derived fibrinogen measurement in the presence of the drug. Aliquots of pooled normal plasma were spiked with different concentrations of dabigatran to reflect in vivo on-therapy levels as well as levels observed in cases of massive accumulation of the drug. Of the routine coagulation assays, in ascending order of sensitivity to dabigatran were PT, APTT and TT. The von Clauss method of measuring fibrinogen using a reagent with low thrombin concentration was affected even at drug levels corresponding to in vivo trough concentrations, whereas the reagent with higher thrombin concentration was only affected at drug levels that were above observed peak concentrations in patients taking 150 mg of the drug twice daily. PT-derived fibrinogen was affected at approximately in vivo peak drug concentrations. The D-dimer assay was affected only at drug concentrations well above peak drug levels. Attempts at in vitro neutralisation of the drug with DOAC-Stop resulted in 'correction' of some of these measurements depending on drug concentration. Like the routine coagulation assays, there is a dabigatran concentration dependent effect on the accuracy of fibrinogen and D-dimer assays. Falsely low fibrinogen results due to dabigatran may confound the assessment of DIC and diagnostic laboratories need to evaluate the performance of their own reagents.

Assessment of acquired activated protein C resistance with the FibWave and comparison with the ETP-based APC resistance.

INTRODUCTION: Activated protein C (APC) resistance is a major risk factor of venous thrombosis which may be acquired by hormonal therapy or other causes. The FibWave, a sensitive global clot-based assay design to analyze the coagulation kinetics in plasma, may be a good candidate to assess this prothrombotic state. This study aims to assess the suitability of the FibWave to differentiate the coagulation kinetics of women on oral contraceptives. MATERIALS AND METHODS: Fifty-four healthy volunteers were divided into 5 groups: men [n = 13], women not using hormonal contraception [n = 12], women using second [n = 12] or third generation [n = 12] combined oral contraceptives, and women using progestin only contraceptive [n = 5]. Patients with coagulation abnormalities were also assessed [n = 8]. The APC resistance was assessed on the FibWave using exogenous APC or Protac, and on the Calibrated Automated Thrombogram using the ETP-based APC resistance assay. RESULTS: Either in presence or in absence of APC or Protac, the FibWave was able to detect a hypercoagulable state in plasma samples. All combined oral contraceptives showed a lower FW-Max1 , FW-Max2, and FW-Min2 percentage of inhibition and a lower FW-Ttpeak ratio than the other groups. The sensitivity of the FibWave was similar to the one of the ETP-based APC resistance assay. CONCLUSION: The FibWave is able to differentiate APC resistance levels observed in women on combined oral contraceptive. The FW-Max1 , FW-Max2, and to a lesser degree FW-Min2 were identified as the most sensitive parameters with a similar performance to the ETP-based APC resistance assay.

Performance Assessment of a Multifaceted Unfractionated Heparin Dosing Protocol in Adult Patients on Extracorporeal Membrane Oxygenator.

BACKGROUND: The use of extracorporeal membrane oxygenator (ECMO) support devices are associated with complications, including bleeding and thrombosis. Unfractionated heparin (UFH) is the gold standard anticoagulant in ECMO patients. Clinically, UFH is monitored through activated clotting time (ACT), activated partial thromboplastin time (aPTT), and anti-factor Xa assay. It is unknown which assay best predicts anticoagulation effects in adults. OBJECTIVE: To assess the correlation of UFH dosing and monitoring using an established protocol. METHODS: A pilot, prospective cohort, historically controlled study was conducted at a tertiary care hospital. Patients ≥18 years-old who received ECMO on the multifaceted anticoagulation protocol were included and compared with those on the conventional method of anticoagulation. The primary end point was to assess the correlation between UFH dose and different monitoring methods throughout 72 hours using the new protocol guided by ACT and anti-factor Xa assay. RESULTS: In each arm, 20 patients were enrolled. The study revealed that anti-factor Xa assay had the largest number of "strong" correlations 11/20 (55%), followed by both aPTT and aPTT ratio 10/20 (50%), and, finally, ACT 2/20 (10%). Concordance between anti-factor Xa assay and the other monitoring parameters in the prospective arm was generally low: 31% with aPTT ratio, 26% with ACT, and 23% with aPTT. CONCLUSION AND RELEVANCE: The adaption of a multifaceted anticoagulation protocol using anti-factor Xa assay may provide a better prediction of heparin dosing in adults ECMO patients compared with the conventional ACT-based protocol. Further studies are needed to assess the safety and different monitoring modalities.

Description of Bivalirudin Use for Anticoagulation in Pediatric Patients on Mechanical Circulatory Support.

BACKGROUND: Although heparin has previously been the anticoagulant of choice during mechanical circulatory support (MCS), there is a lack of consistency in dose-response in pediatric patients. Bivalirudin offers more consistent dose-response in adults; however, there are limited data for pediatrics use. OBJECTIVE: The purpose was to characterize the usage, dosage, and safety profile of bivalirudin when used for pediatric MCS in a tertiary care pediatric hospital. METHODS: A retrospective review of pediatric patients receiving bivalirudin for extracorporeal membrane oxygenation/ventricular assist device (ECMO/VAD) anticoagulation was conducted. The primary outcome was the average dose of bivalirudin. Additional outcomes included initial and maximum bivalirudin dose, time to first therapeutic activated partial thromboplastin time (aPTT), time within goal aPTT range, bleeding and clotting complications, and cost. Data were compared between ECMO and VAD patients. RESULTS: Thirty-four patients were included. The median dose of bivalirudin was 0.37 mg/kg/h (interquartile range [IQR] = 0.21-0.56), with a maximum dose of 0.62 mg/kg/h (IQR = 0.33-0.91). VAD patients had a higher median and maximum dose as compared with ECMO patients. Patients achieved their therapeutic goal in a median of 6.1 hours and averaged 61.9% time within therapeutic aPTT. One patient had significant hemorrhage, whereas 3 patients had clotting requiring a circuit change. Bivalirudin acquisition cost was higher than heparin. CONCLUSION AND RELEVANCE: Bivalirudin dosing in ECMO and VAD patients is consistent with dosing seen in previous reports but may be higher in VAD patients. Comparative studies between heparin and bivalirudin are necessary to compare cost-effective outcomes for pediatric patients.

Health-related quality of life correlates with time in therapeutic range in children on anticoagulants with International Normalised Ratio self-monitoring.

BACKGROUND: Managing oral anticoagulant therapy with vitamin K antagonists remains challenging in paediatric medicine. AIMS: This study aimed to assess the correlation between time in therapeutic range and quality of life in children participating in a non-selective International Normalised Ratio self-monitoring and vitamin K antagonist education programme. METHODS: Children aged from 2 to 18 years and receiving vitamin K antagonist therapy were eligible for this prospective multicentre study. Clinical and demographic data were collected. Health-related quality of life was assessed using the PedsQL™ 4.0 questionnaire. Correlations between quality of life scores and time in therapeutic range were measured. RESULTS: A total of 121 children were included in the study (mean age 9.6±4.9 years). Cardiac conditions were the predominant indication for vitamin K antagonists. The mean time in therapeutic range was 0.78±0.15 overall, and 0.76±0.24 over the 3-month period before quality of life assessment. The mean total quality of life score was 76.2±18 in self reports, 71.4±22 in mother reports and 73.5±19 in father reports. The time in therapeutic range correlated with the total quality of life scores in self reports (r=0.22; P=0.04), mother reports (r=0.23; P=0.02) and father reports (r=0.28; P=0.02). The time in therapeutic range predominantly correlated with school functioning in self reports (r=0.38; P=0.002) and mother reports (r=0.40; P<0.001), and with physical functioning in father reports (r=0.28; P=0.03). CONCLUSIONS: Time in therapeutic range correlated with quality of life in children participating in a non-selective International Normalised Ratio self-monitoring and vitamin K antagonist education programme. Regular assessment of quality of life in patient education programmes contributes towards understanding the concerns and needs of patients.

The hypercoagulable state in COVID-19: Incidence, pathophysiology, and management.

The 2019 coronavirus disease (COVID-19) presents with a large variety of clinical manifestations ranging from asymptomatic carrier state to severe respiratory distress, multiple organ dysfunction and death. While it was initially considered primarily a respiratory illness, rapidly accumulating data suggests that COVID-19 results in a unique, profoundly prothrombotic milieu leading to both arterial and venous thrombosis. Consistently, elevated D-dimer level has emerged as an independent risk factor for poor outcomes, including death. Several other laboratory markers and blood counts have also been associated with poor prognosis, possibly due to their connection to thrombosis. At present, the pathophysiology underlying the hypercoagulable state is poorly understood. However, a growing body of data suggests that the initial events occur in the lung. A severe inflammatory response, originating in the alveoli, triggers a dysfunctional cascade of inflammatory thrombosis in the pulmonary vasculature, leading to a state of local coagulopathy. This is followed, in patients with more severe disease, by a generalized hypercoagulable state that results in macro- and microvascular thrombosis. Of concern, is the observation that anticoagulation may be inadequate in many circumstances, highlighting the need for alternative or additional therapies. Numerous ongoing studies investigating the pathophysiology of the COVID-19 associated coagulopathy may provide mechanistic insights that can direct appropriate interventional strategies.

Management of Anticoagulant Treatment and Anticoagulation-Related Complications in Nonagenarians.

Given the aging population, the burden of age-dependent diseases is growing. Despite this, elderly patients are often underrepresented in clinical trials and little data are available on current anticoagulant management and outcomes in this unique population, especially those aged 90 years or older. There is uncertainty, and a fear of "doing harm," that often leads to de-prescription of antithrombotic agents in nonagenarian patients. Decision-making concerning the use of anticoagulant treatment needs to balance the risk of thrombotic events against the risk of major bleeding, especially intracranial hemorrhage. In this perspective, the development of direct oral anticoagulants (DOACs), acting as direct and selective inhibitors of a specific step or enzyme of the coagulation cascade, has dramatically changed oral anticoagulant treatment. In fact, given the lower incidence of intracranial hemorrhage, the favorable overall efficacy and safety, and the lack of routine monitoring, DOACs are the currently recommended anticoagulant agents for the treatment of both atrial fibrillation and venous thromboembolism even in very elderly patients. However, given the limited data available on the management of anticoagulation in nonagenarians, a few unanswered questions remain. In this review, we focused on recent evidence for anticoagulant treatment in atrial fibrillation and venous thromboembolism along with management of anticoagulation-related bleeding in nonagenarians.

Assessment of the effects of sugammadex on coagulation profiles using thromboelastographic parameters.

This study evaluated the effects of sugammadex at conventional doses of 2 and 4 mg/kg on the coagulation profile by analyzing thromboelastographic parameters and performing a traditional laboratory coagulation analysis. A total of 100 patients undergoing arthroscopic shoulder surgery were enrolled. The patients were randomly divided into the 2 mg and 4 mg groups. The laboratory coagulation test and thromboelastographic analysis were performed before and 15 min after administering sugammadex. Prothrombin time (PT) was significantly prolonged after sugammadex administration than before it in intragroup comparisons of the 2 mg group (12.8 ± 0.6 s vs. 13.6 ± 0.7 s, p < 0.001) and the 4 mg group (13.0 ± 0.5 s vs. 13.7 ± 0.5 s, p < 0.001). R time, derived from thromboelastography, was also significantly prolonged after sugammadex administration (4.7 ± 1.8 min vs. 5.8 ± 2.1 min, p = 0.005). In conclusion, the conventional doses of 2 or 4 mg/kg sugammadex prolonged PT. Sugammadex 4 mg/kg also prolonged R time, although the value was within the normal range. Therefore, physicians should be cautious with the higher sugammadex dose, particularly in patients with a high risk of bleeding because the higher dose was associated with less coagulation.Trial registration: KCT0002133 (https://cris.nih.go.kr).

Direct Oral Anticoagulant Use: A Practical Guide to Common Clinical Challenges.

Direct oral anticoagulants (DOACs) have quickly become attractive alternatives to the long-standing standard of care in anticoagulation, vitamin K antagonist. DOACs are indicated for prevention and treatment of several cardiovascular conditions. Since the first approval in 2010, DOACs have emerged as leading therapeutic alternatives that provide both clinicians and patients with more effective, safe, and convenient treatment options in thromboembolic settings. With the expanding role of DOACs, clinicians are faced with increasingly complex decisions relating to appropriate agent, duration of treatment, and use in special populations. This review will provide an overview of DOACs and act as a practical reference for clinicians to optimize DOAC use among common challenging scenarios. Topics addressed include (1) appropriate indications; (2) use in patients with specific comorbidities; (3) monitoring parameters; (4) transitioning between anticoagulant regimens; (5) major drug interactions; and (6) cost considerations.

Tortuosity-powered microfluidic device for assessment of thrombosis and antithrombotic therapy in whole blood.

Accurate assessment of blood thrombosis and antithrombotic therapy is essential for the management of patients in a variety of clinical conditions, including surgery and on extracorporeal life support. However, current monitoring devices do not measure the effects of hemodynamic forces that contribute significantly to coagulation, platelet function and fibrin formation. This limits the extent to which current assays can predict clotting status in patients. Here, we demonstrate that a biomimetic microfluidic device consisting stenosed and tortuous arteriolar vessels would analyze blood clotting under flow, while requiring a small blood volume. When the device is connected to an inline pressure sensor a clotting time analysis is applied, allowing for the accurate measurement of coagulation, platelets and fibrin content. Furthermore, this device detects a prolonged clotting time in clinical blood samples drawn from pediatric patients on extracorporeal membrane oxygenation receiving anticoagulant therapy. Thus, this tortuosity activated microfluidic device could lead to a more quantitative and rapid assessment of clotting disorders and their treatment.

Assessment of patient knowledge on warfarin: An item response theory approach.

WHAT IS KNOWN AND OBJECTIVE: There are no instruments to assess the patient's knowledge of oral anticoagulation with warfarin, in which the performance of the items has been evaluated through the item response theory. To evaluate psychometric properties of the Brazilian version of the Oral Anticoagulation Knowledge Test, using the item response theory. METHODS: This methodological study was developed in an anticoagulation clinic of a university hospital with a sample of 201 patients treated with warfarin. The item response theory was used to evaluate questions regarding psychometric properties and the performance of the Brazilian version of the Oral Anticoagulation Knowledge Test items. The unidimensionality hypothesis was analysed by decomposing the polychoric correlation and the Cronbach's alpha coefficient. An item characteristic curve of the 20 items of the instrument was made to identify the discrimination power of each item of the performance scale. RESULTS AND DISCUSSION: Correlations were positive and statistically significant among the 20 items, with a Cronbach's alpha coefficient of 0.82. The difficulty parameter ranged from -4.14 to 0.42. The discrimination parameter ranged from 0.41 to 1.89. The items regarding drug-drug/drug-food interactions were able to differentiate knowledge about oral anticoagulation with greater accuracy. WHAT IS NEW AND CONCLUSION: This study is the first that uses this methodology to evaluate the knowledge on oral anticoagulation therapy with warfarin. The evaluation using item response theory showed that the Brazilian version of the Oral Anticoagulation Knowledge Test is suitable for assessing the patient's knowledge of oral anticoagulation with warfarin. Thus, our findings confirmed the utility of this instrument and provided an essential point of reference for the structuring of health education activities that ensure the individualization of educational interventions in patients on warfarin.

When to Admit to Observation: Predicting Length of Stay for Anticoagulated Elderly Fall Victims.

BACKGROUND: Geriatric patients who fall while taking an anticoagulant have a small but significant risk of delayed intracranial hemorrhage requiring observation for 24 h. However, the medical complexity associated with geriatric care may necessitate a longer stay in the hospital. Little is known about the factors associated with a successful observational status stay (<2 d) for this population. MATERIALS AND METHODS: Elderly patients who fell while taking an anticoagulant admitted from 2012 to 2017 at an ACS level II trauma center were included in a retrospective cohort study to determine what factors were associated with a stay consistent with observational status. INCLUSION CRITERIA: age> 65 y old, negative initial head CT, and one of the following: INR>3.5 if on warfarin, GCS<14, external signs of trauma, or focal neurological deficits. RESULTS: The cohort included 369 patients. Factors associated with decreased likelihood of successful observational status included the need for services after discharge such as an extended care facility (OR 0.06, 95% CI 0.02-0.19, P < 0.001) or visiting nurse agency services (OR 0.27, 95% CI 0.10-0.75, P < 0.001), a dementia diagnosis (OR 0.17, 95% CI 0.04-0.70, P = 0.014), increasing number of medications (OR 0.91, 95% CI 0.84-0.99, P = 0.031), and the use of coumadin (OR 0.28, 95% CI 0.12-0.70, P = 0.006). CONCLUSIONS: For trauma providers, knowing your patient's medication use and particularly type of anticoagulant, comorbidities including dementia, and likely need for services after discharge will help guide the decision to admit the patient for what may be a reasonably lengthy stay versus a brief observation in the hospital for elderly fall victims on anticoagulation.