Intramuscular administration of tranexamic acid in a large swine model of hemorrhage with hyperfibrinolysis

BACKGROUND

Traumatic injury with subsequent hemorrhage is one of the leading causes of mortality among military personnel and civilians alike. Posttraumatic hemorrhage accounts for 40% to 50% of deaths in severe trauma patients occurring secondary to direct vessel injury or the development of trauma-induced coagulopathy (TIC). Hyperfibrinolysis plays a major role in TIC and its presence increases a patient's risk of mortality. Early therapeutic intervention with intravenous (IV) tranexamic acid (TXA) prevents development of hyperfibrinolysis and subsequent TIC leading to decreased mortality. However, obtaining IV access in an austere environment can be challenging. In this study, we evaluated the efficacy of intramuscular (IM) versus IV TXA at preventing hyperfibrinolysis in a hemorrhaged swine.

METHODS

Yorkshire cross swine were randomized on the day of study to receive IM or IV TXA or no treatment. Swine were sedated, intubated, and determined to be hemodynamically stable before experimentation. Controlled hemorrhaged was induced by the removal of 30% total blood volume. After hemorrhage, swine were treated with 1,000 mg of IM or IV TXA. Control animals received no treatment. Thirty minutes post-TXA treatment, fibrinolysis was induced with a 50-mg bolus of tissue plasminogen activator. Blood samples were collected to evaluate blood TXA concentrations, blood gases, blood chemistry, and fibrinolysis.

RESULTS

Blood TXA concentrations were significantly different between administration routes at the early time points but were equivalent by 20 minutes after injection, remaining consistently elevated for up to 3 hours postadministration. Induction of fibrinolysis resulted in 87.18 ± 4.63% lysis in control animals, compared with swine treated with IM TXA, 1.96 ± 2.66% and 1.5 ± 0.42% lysis in the IV TXA group.

CONCLUSION

In the large swine model of hemorrhage with hyperfibrinolysis, IM TXA is bioequivalent and equally efficacious in preventing hyperfibrinolysis as IV TXA administration.

Rare bleeding disorders: Advances in management

Inherited factor coagulation deficiencies and vascular bleeding disorders, associated with bleeding of various severity, are often classified as rare bleeding disorders (RBDs). These include inherited fibrinogen disorders, inherited platelet function disorders (IPFD) and hereditary haemorrhagic telangiectasia (HHT). In the last decades, there have been large increases in knowledge on the epidemiology, genetics, physiopathology, clinical features, and diagnosis of RBDs, but improvements in management have been more limited and remain challenging. The treatment mainstay of RBDs is based only on replacement of a few available coagulation factor concentrates or cryoprecipitates. There is growing interest in therapeutic agents that enhance coagulation or inhibiting anticoagulant pathways in RBDs. In severe IPFD, the optimal platelet transfusion strategy is not yet established. Moreover, data is scarce on the effectiveness and safety of desmopressin and/or antifibrinolytic drugs often used for milder IPFD treatment. The best fibrinogen replacement strategy (prophylaxis vs. on demand) in afibrinogenemia is still debated. Similarly, the optimal trough fibrinogen target level for treatment of acute bleeding, and the role of fibrinogen replacement during pregnancy in mild hypofibrinogenemia and dysfibrinogenemia, have not been properly evaluated. The therapeutic arsenal in HHT includes antifibrinolytics and a series of antiangiogenic agents whose potential efficacy has been tested in small studies or are under investigation for treatment of bleeding. However, there is need to address several issues, including the optimal dosing strategies, the potential emergent toxicity of longer-term use, and the impact of systemic antiangiogenic treatment on visceral arteriovenous malformations.

Rapid clearing CT-001 restored hemostasis in mice with coagulopathy induced by activated protein C

BACKGROUND

Activated protein C (APC) is one of the mechanisms contributing to coagulopathy, which is associated with high mortality. The counteraction of the APC pathway could help ameliorate bleeding. However, patients also transform frequently from a hemorrhagic state to a prothrombotic state at a later time. Therefore, a prohemostatic therapeutic intervention should take this thrombotic risk into consideration.

OBJECTIVES

CT-001 is a novel factor VIIa (FVIIa) with enhanced activity and desialylated N-glycans for rapid clearance. We assessed CT-001 clearance in multiple species and its ability to reverse APC-mediated coagulopathic blood loss.

METHODS

The N-glycans on CT-001 were characterized by liquid chromatography-mass spectrometry. Three species were used to evaluate the pharmacokinetics of the molecule. The potency and efficacy of CT-001 under APC pathway-induced coagulopathic conditions were assessed by coagulation assays and bleeding models.

RESULTS

The N-glycosylation sites of CT-001 had high occupancy of desialylated N-glycans. CT-001 exhibited 5 to 16 times higher plasma clearance in human tissue factor knockin mice, rats, and cynomolgus monkeys than wildtype FVIIa. CT-001 corrected the activated partial thromboplastin time and thrombin generation of coagulopathic plasma to normal in in vitro studies. In an APC-mediated saphenous vein bleeding model, 3 mg/kg of CT-001 reduced bleeding time in comparison with wildtype FVIIa. The correction of bleeding by CT-001 was also observed in a coagulopathic tail amputation severe hemorrhage mouse model. The efficacy of CT-001 is independent of the presence of tranexamic acid, and the combination of CT-001 and tranexamic acid does not lead to increased thrombogenicity.

CONCLUSION

CT-001 corrected APC pathway-mediated coagulopathic conditions in preclinical studies and could be a potentially safe and effective procoagulant agent for addressing APC-mediated bleeding.

Prevention of Venous Thromboembolism in Medical Patients with Thrombocytopenia or with Platelet Dysfunction: The Last 10 Years

Current guideline recommendations for primary prophylaxis of venous thromboembolism (VTE) are based on randomized clinical trials that usually exclude subjects at a potentially high risk of bleeding complications. For this reason, no specific guideline is available for thromboprophylaxis in hospitalized patients with thrombocytopenia and/or platelet dysfunction. However, except in patients with absolute contraindications to anticoagulant drugs, antithrombotic prophylaxis should always be considered, for example, in hospitalized cancer patients with thrombocytopenia, especially in those with multiple VTE risk factors. Low platelet number, platelet dysfunction, and clotting abnormalities are also very common in patients with liver cirrhosis, but these patients have a high incidence of portal venous thrombosis, implying that cirrhotic coagulopathy does not fully protect against thrombosis. These patients may benefit from antithrombotic prophylaxis during hospitalization. Patients hospitalized for COVID-19 need prophylaxis, but frequently experience thrombocytopenia or coagulopathy. In patients with antiphospholipid antibodies, a high thrombotic risk is usually present, even in the presence of thrombocytopenia. VTE prophylaxis in high-risk conditions is thus suggested in these patients. At variance with severe thrombocytopenia (< 50,000/mm3), mild/moderate thrombocytopenia (≥ 50,000/mm3) should not interfere with VTE prevention decisions. In patients with severe thrombocytopenia, pharmacological prophylaxis should be considered on an individual basis. Aspirin is not as effective as heparins in lowering the risk of VTE. Studies in patients with ischemic stroke demonstrated that thromboprophylaxis with heparins is safe in these patients also during antiplatelet treatment. The use of direct oral anticoagulants in the prophylaxis of VTE in internal medicine patients has been recently evaluated, but no specific recommendation exists for patients with thrombocytopenia. The need for VTE prophylaxis in patients on chronic treatment with antiplatelet agents should be evaluated after assessing the individual risk of bleeding complications. Finally, the selection of patients who require post-discharge pharmacological prophylaxis remains debated. New molecules currently under development (such as the inhibitors of factor XI) may contribute to improve the risk/benefit ratio of VTE primary prevention in this setting of patients.

Efficacy and safety of heparin for sepsis-induced disseminated intravascular coagulation (HepSIC): study protocol for a multicenter randomized controlled trial

BACKGROUND

Disseminated intravascular coagulation (DIC) occurs in 30-50% of septic patients and contributes to high mortality in the intensive care unit (ICU). However, there are few proven interventions for coagulation disorder management in sepsis. Experimental and clinical data have demonstrated that sepsis could benefit from unfractionated heparin (UFH) treatment. To date, there are no large multicenter trials to determine the safety and efficacy of UFH in septic patients with suspected DIC.

METHODS

A multicenter, double-blinded, placebo-controlled randomized trial is designed to recruit 600 patients who met sepsis 3.0 criteria and suspected DIC. Participants will be randomized (1:1) to receive UFH or saline via continuous intravenous administration for 7 days within 6 h of enrolment. The primary outcome is ICU mortality. The secondary outcome includes 28-day all-cause mortality, the improvement of Sequential Organ Failure Assessment scores, and the incidence of major hemorrhage. Investigators, participants, and statisticians will be blinded to the allocation.

DISCUSSION

The HepSIC trial is to evaluate the efficacy and safety of UFH on sepsis-related DIC across different areas of China. The small dosage of UFH administration would offer a new potential approach for treating sepsis-related coagulation disorders.

ETHICS AND DISSEMINATION

Ethical approval was granted by all the ethics committees of 20 participant centers. Results will be disseminated via peer-reviewed publications and presented at conferences.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02654561. Registered on 13 January 2016.

Analysis of fibrinolytic shutdown in trauma patients with traumatic brain injury

BACKGROUND

Coagulation profiles following major trauma vary depending on injury pattern and degree of shock. The physiologic mechanisms involved in coagulation function at any given time are varied and remain poorly understood. Thromboelastography (TEG) has been used evaluate coagulation profiles in the trauma population with some reports demonstrating a spectrum of fibrinolysis to fibrinolytic shutdown on initial presentation. The objective of this study was to evaluate the fibrinolytic profile of patients with TBI using thromboelastography (TEG). We hypothesized that patients with TBI would demonstrate low fibrinolytic activity.

METHODS

All trauma activations at an ACS-verified level 1 trauma center received a TEG analysis upon arrival from December 2019 to June 2021. A retrospective review of the results and outcomes was conducted, and TBI patients were compared to patients without TBI. Linear regression was used to evaluate the effect of patient and injury factors on fibrinolysis. Hyperfibrinolysis was defined as LY30 ​> ​7.7%, physiologic fibrinolysis as LY30 0.6-7.7%, and fibrinolytic shutdown as LY30 ​< ​0.6%.

RESULTS

A total of 1369 patients received an admission TEG analysis. Patients with TBI had a significantly higher median ISS (16 vs. 8, p ​< ​0.001), lower median admission Glasgow Coma Scale (14 vs. 15, p ​< ​0.001), longer intensive care unit length of stay (3 vs. 2 days, p ​< ​0.0001), increased ventilator days (216 vs. 183, p ​< ​0.001), higher mortality (14.6% vs. 5.1%, p ​< ​0.001), but lower shock index (0.6 vs. 0.7, p ​< ​0.0001) compared to those without TBI. Median LY30 was found to be decreased in the TBI group (0.1 vs. 0.2, p ​= ​0.0006). Patients with TBI were found to have a higher rate of fibrinolytic shutdown compared those without TBI (68.7% vs. 63.5%, p ​= ​0.054). ISS, sex, and shock index were found to be predictive of LY30 on linear regression, but TBI was not (Β: 0.09, SE: 0.277, p ​= ​0.745). The rate of DVT/PE did not appear to be elevated in patients with TBI (0.8%) and without TBI (1.2%).

CONCLUSIONS

Trauma patients with and without TBI were found to have high rates of fibrinolytic shutdown. Although there was a high incidence of fibrinolytic shutdown, it did not appear to have an impact on the rate of thrombotic complications. The clinical significance of these results is unclear and differs significantly from recent reports which demonstrated that TBI is associated with a 25% rate of fibrinolytic shutdown. Further investigation is needed to better define the fibrinolytic pathway in patients with trauma and TBI to develop optimal treatment algorithms.

[Assessment of a therapeutic protocol for the management of snakebite envenomations in Benin]

Introduction

Snakebite envenomation is a major public health issue in Sub-Saharan Africa (SSA). Antivenoms are the only etiological treatment. However, the dose recommended by the manufacturer (2 vials renewed every 2 hours in case of persistent bleeding) is usually not applied due to the high cost which is borne only by the patient. Based on clinical presentation, we evaluated the administration of a single vial on admission (instead of 2 vials), which corresponds to the therapeutic protocol used in current practice in most health centers in Benin and beyond in SSA. Renewal of antivenom followed manufacturer's recommendation.

Material and method

The study took place in a first referral hospital in Tanguiéta, North Benin. All envenomed patients received a slow intravenous vial of Inoserp® Pan-Africa (IPA) upon arrival. A clinical assessment identical to that of inclusion was carried out 2, 4, 6, 12 and 24 hours later to assess the tolerance and efficacy of the IPA, as well as the need to readminister the antivenom. The occurrence, persistence or worsening of clinical hemorrhages or neurological disorders, the latter reflecting envenomation by elapids, systematically led to the injection of 2 or 4 vials of IPA, respectively. Signs of intolerance were sought before and after each administration of antivenom, then 2 weeks to 1 month after treatment, in order to estimate the incidence of adverse effects attributable to the antivenom. Efficacy of IPA was assessed by cessation of bleeding and/or normalization of whole blood coagulation test (WBCT) within 24 hours of initial administration.

Results

The study took place from July 31 to October 31, 2019. We received 53 cases of snakebites of which 43 were included. The median age was 21 [IQR: 18-31] years and the sex ratio (M/F) was 1.5. Farmers were the majority (48%). The median time to admission was 1 [IQR: 0-2] day. On admission, 32 patients (74%) presented hemostasis disorders marked by bleeding and/or abnormal WBCT. None of the patients showed neurological symptoms. The median time to normalization of WBCT was 24 [IQR: 4-72] hours. The median time to stop bleeding was 6 [IQR: 4-12] hours. In 3 of the 11 patients whose bleeding had stopped at H2, a recurrence occurred within the following 24 hours. In addition, 3 patients presented with late bleeding 24 hours after admission. Two patients (5%) died as a result of envenomation.

Discussion/conclusion

The simplified protocol represents a significant saving in the number of vials used, i.e. 1.8±0.4 vials per patient instead of the 2.4±0.2 which would have been necessary in these same patients treated according to the standard protocol (p = 2.6·10-4). However, in comparison with the results obtained during the previous clinical study, the cessation of bleeding is delayed, as is the normalization of the WBCT at the different follow-up times. In addition, the number of re-administrations of antivenom after H2 is higher in the light protocol than in the standard one, respectively 13 patients out of 43 treated versus 4 patients out of 59 (p = 0.006). There was no significant difference between the incidence of signs of early antivenom intolerance in this study compared to the previous one (16% and 11%, respectively; p = 0.79). This delay can put up to a third of patients at risk of complications. Despite its effectiveness and the antivenom savings made, it does not seem reasonable to recommend it.

The use of vitamin K for coagulopathy in critically ill children

OBJECTIVES

Coagulopathy is associated with increased mortality in children in the intensive care unit (ICU). Recommended management of vitamin K-deficient coagulopathy is vitamin K administration. The goal of this study was to evaluate vitamin K administration for coagulopathy in critically ill children and determine a relationship between vitamin K dose and change in prothrombin time (PT) and international normalized ratio (INR).

METHODS

This retrospective cohort study reviewed electronic medical records of patients ≤17 years who received vitamin K for acute coagulopathy in the pediatric ICU from January 2013 to January 2021. Patients receiving vitamin K antagonists were excluded. Effectiveness data included change in PT/INR after vitamin K administration. Safety data included incidence of hypersensitivity or anaphylaxis.

RESULTS

A total of 310 patients (median age 6.8 years, range 22 days-17.7 years) received vitamin K. A median of three doses (range 1-8) and 0.14 mg/kg per dose (range 0.09-0.22 mg/kg) were given, most frequently intravenously (892/949, 94%). Most patients (304/310, 98%) had at least one risk factor for vitamin K deficiency. Mean PT/INR was 21.5/2.1 prior to vitamin K administration, which decreased by 4.4 (SD = 9.0, 95% CI 16.011 to 18.015, p < 0.001) and 0.5 (SD = 1.0, 95% CI 1.490 to 1.705, p < 0.001) to means of 17.0 and 1.6, respectively, after the first vitamin K dose. No linear relationship was found between vitamin K dose and change in PT/INR. No hypersensitivity or anaphylaxis occurred following vitamin K administration; 27% (84/310) of patients died.

CONCLUSIONS

Administration of vitamin K is effective and safe for the management of vitamin K-deficient coagulopathy in critically ill pediatric patients. Further study is needed to determine a relationship between vitamin K dose and change in PT/INR.

Viscoelastic coagulation testing in Neonatal Intensive Care Units: advantages and pitfalls in clinical practice

The expression "developmental hemostasis" indicates the age-related physiological changes occurring during the maturational process of the hemostatic system. Despite the quantitative and qualitative alterations, the neonatal hemostatic system is competent and well-balanced. Conventional coagulation tests do not provide reliable information as they only explore the procoagulants during the neonatal period. In contrast, viscoelastic coagulation tests (VCTs), such as viscoelastic coagulation monitoring (VCM), thromboelastography (TEG or ClotPro), and rotational thromboelastometry (ROTEM), are point-of-care assays that provide a quick, dynamic and global view of the hemostatic process, allowing prompt and individualized therapeutic intervention when necessary. Their use in neonatal care is on the increase and they could help monitor patients at risk of hemostatic derangement. In addition, they are crucial for anticoagulation monitoring during extracorporeal membrane oxygenation. Moreover, implementing VCT-based monitoring could optimize blood product use.

Prothrombin complex concentrate (PCC) for treatment of trauma-induced coagulopathy: systematic review and meta-analyses

BACKGROUND

Trauma-induced coagulopathy (TIC) is common in trauma patients with major hemorrhage. Prothrombin complex concentrate (PCC) is used as a potential treatment for the correction of TIC, but the efficacy, timing, and evidence to support its use in injured patients with hemorrhage are unclear.

METHODS

A systematic search of published studies was performed on MEDLINE and EMBASE databases using standardized search equations. Ongoing studies were identified using clinicaltrials.gov. Studies investigating the use of PCC to treat TIC (on its own or in combination with other treatments) in adult major trauma patients were included. Studies involving pediatric patients, studies of only traumatic brain injury (TBI), and studies involving only anticoagulated patients were excluded. Primary outcomes were in-hospital mortality and venous thromboembolism (VTE). Pooled effects of PCC use were reported using random-effects model meta-analyses. Risk of bias was assessed for each study, and we used the Grading of Recommendations Assessment, Development, and Evaluation to assess the quality of evidence.

RESULTS

After removing duplicates, 1745 reports were screened and nine observational studies and one randomized controlled trial (RCT) were included, with a total of 1150 patients receiving PCC. Most studies used 4-factor-PCC with a dose of 20-30U/Kg. Among observational studies, co-interventions included whole blood (n = 1), fibrinogen concentrate (n = 2), or fresh frozen plasma (n = 4). Outcomes were inconsistently reported across studies with wide variation in both measurements and time points. The eight observational studies included reported mortality with a pooled odds ratio of 0.97 [95% CI 0.56-1.69], and five reported deep venous thrombosis (DVT) with a pooled OR of 0.83 [95% CI 0.44-1.57]. When pooling the observational studies and the RCT, the OR for mortality and DVT was 0.94 [95% CI 0.60-1.45] and 1.00 [95% CI 0.64-1.55] respectively.

CONCLUSIONS

Among published studies of TIC, PCCs did not significantly reduce mortality, nor did they increase the risk of VTE. However, the potential thrombotic risk remains a concern that should be addressed in future studies. Several RCTs are currently ongoing to further explore the efficacy and safety of PCC.

The Crosstalk between Nephropathy and Coagulation Disorder: Pathogenesis, Treatment, and Dilemmas

ABSTRACT

The interaction between the kidney and the coagulation system greatly affects each other because of the abundant vessel distribution and blood perfusion in the kidney. Clinically, the risks of complicated thrombosis and bleeding have become important concerns in the treatment of nephropathies, especially nephrotic syndrome, CKD, ESKD, and patients with nephropathy undergoing RRTs. Adverse effects of anticoagulant or procoagulant therapies in patients with nephropathy, especially anticoagulation-related nephropathy, heparin-induced thrombocytopenia, and bleeding, seriously worsen the prognosis of patients, which have become challenges for clinicians. Over the decades, the interaction between the kidney and the coagulation system has been widely studied. However, the effects of the kidney on the coagulation system have not been systematically investigated. Although some coagulation-related proteins and signaling pathways have been shown to improve coagulation abnormalities while avoiding additional kidney damage in certain kidney diseases, their potential as anticoagulation targets in nephropathy requires further investigation. Here, we review the progression of research on the crosstalk between the coagulation system and kidney diseases and systematically analyze the significance and shortcomings of previous studies to provide new sight into future research. In addition, we highlight the status of clinical treatment for coagulation disorder and nephropathy caused by each other, indicating guidance for the formulation of therapeutic strategies or drug development.

The prevalence and risk factors of coagulopathy in pediatric patients undergoing surgery for epilepsy

OBJECTIVE

Hematological consequences of novel antiseizure medications (ASMs) or combined therapies are rarely reported, especially in pediatric patients undergoing surgery for epilepsy. This study aimed to assess the prevalence and risk factors of coagulation dysfunction in this population and evaluate their relationship with intra- and postoperative bleeding.

METHODS

Three hundred ninety children who underwent surgery for epilepsy and 104 children without epilepsy who underwent nonepilepsy surgery at the authors' center were included in the study. The authors retrospectively collected and analyzed the following clinical data: sex, age, weight, course of epilepsy, antiseizure therapy, first laboratory data after admission, and transfusion-related data.

RESULTS

ASMs were responsible for the higher incidence of coagulation dysfunction in pediatric epilepsy surgery patients. Low body weight (OR 0.95, 95% CI 0.92-0.98) and valproic acid (VPA) therapy (OR 5.13, 95% CI 3.25-8.22) were the most relevant factors leading to coagulation dysfunction. The most common hematological side effects of VPA were thrombocytopenia and hypofibrinogenemia, whereas low body weight was only associated with hypofibrinogenemia. Both VPA and low body weight increased the need for intra- or postoperative transfusion (p < 0.001).

CONCLUSIONS

Pediatric epilepsy surgery patients often take multiple ASMs, resulting in an increased incidence of coagulopathy. VPA levels and low body weight were found to be the main influential factors associated with an increased risk of coagulation dysfunction. Platelet and fibrinogen levels were the main indices that were affected. Both VPA and low body weight were relevant to additional surgery-related transfusion, necessitating the need for increased awareness of preoperative coagulopathy before pediatric epilepsy surgery. Clinical trial registration no.: NCT05675254 (ClinicalTrials.gov).

High prevalence of heavy menstrual bleeding in women with rare bleeding disorders in the Netherlands: retrospective data from the RBiN study

BACKGROUND

Heavy menstrual bleeding (HMB) is associated with a reduced quality of life and limitations in social and physical functioning. Data on HMB in women with rare bleeding disorders (RBDs), including coagulation factor deficiencies and fibrinolytic disorders, are scarce.

OBJECTIVES

To analyze the prevalence, severity, and treatment of HMB in Dutch women with an RBD.

METHODS

The Rare Bleeding Disorders in the Netherlands (RBiN) study included 263 patients with an RBD from all 6 hemophilia treatment centers (October 2017-November 2019). In this analysis, data of 111 women aged ≥16 years were studied. According to the International Society on Thrombosis and Haemostasis bleeding assessment tool, HMB symptoms were scored from 0 (no/trivial) to 4 (severe symptoms requiring medical intervention). HMB was defined as a score ≥1. Age at RBD diagnosis was extracted from patient files.

RESULTS

HMB was reported by 80% of women (89/111) and was more prevalent in women with a fibrinolytic disorder (33/35; 94%) than in women with a coagulation factor deficiency (56/76; 74%) (P = .011). Of the 89 women with HMB, 82% (n = 73) ever required treatment. Multiple treatment modalities were frequently used, both in severe and mild deficiencies. Hormonal treatment was mostly used (n = 64; 88%), while antifibrinolytics were prescribed less frequently (n = 18; 25%). In women with HMB since menarche (n = 61; 69%), median age at RBD diagnosis was 28 years (IQR, 14-41).

CONCLUSION

HMB is common in women with RBDs. Women with mild deficiencies also frequently reported HMB. Only a minority of women were treated with hemostatic agents. A significant diagnostic delay was observed after the onset of HMB symptoms.

Novel Toxicodynamic Model of Subcutaneous Envenomation to Characterize Snake Venom Coagulopathies and Assess the Efficacy of Site-Directed Inorganic Antivenoms

Venomous snake bite adversely affects millions of people yearly, but few animal models allow for the determination of toxicodynamic timelines with hemotoxic venoms to characterize the onset and severity of coagulopathy or assess novel, site-directed antivenom strategies. Thus, the goals of this investigation were to create a rabbit model of subcutaneous envenomation to assess venom toxicodynamics and efficacy of ruthenium-based antivenom administration. New Zealand White rabbits were sedated with midazolam via the ear vein and had viscoelastic measurements of whole blood and/or plasmatic coagulation kinetics obtained from ear artery samples. Venoms derived from Crotalus scutulatus scutulatus, Bothrops moojeni, or Calloselasma rhodostoma were injected subcutaneously, and changes in coagulation were determined over three hours and compared to samples obtained prior to envenomation. Other rabbits had ruthenium-based antivenoms injected five minutes after venom injection. Viscoelastic analyses demonstrated diverse toxicodynamic patterns of coagulopathy consistent with the molecular composition of the proteomes of the venoms tested. The antivenoms tested attenuated venom-mediated coagulopathy. A novel rabbit model can be used to characterize the onset and severity of envenomation by diverse proteomes and to assess site-directed antivenoms. Future investigation is planned involving other medically important venoms and antivenom development.

Bleeding management in patients with direct oral anticoagulants

Bleeding events in patients under direct oral anticoagulation (DOAC) can be life-threating but are commonly not related to drug overdose. However, a relevant DOAC plasma concentration impairs the hemostasis and should therefore be ruled out immediately after hospital admission. The effect of DOAC is typically not visible in standard coagulation tests such as activated partial thrombin time or thromboplastin time. Specific anti-Xa or anti-IIa assays allow a specific drug monitoring, but they are too time-consuming in critical bleeding events and typically not available 24 h/7 d in routine care. Recent advantages in point-of-care (POC) testing might improve patient care by early exclusion of relevant DOAC levels, but sufficient validation is still lacking. POC urine analysis help to exclude DOAC in emergency patients, but does not provide a quantitative information about plasma concentration. POC viscoelastic testing (VET) can determine the DOAC effect on clotting time and helps further to reveal other concomitant bleeding disorders in emergency, e.g., factor deficiency or hyperfibrinolysis. If a relevant plasma concentration of the DOAC is assumed or was proven by either laboratory assays or POC testing, restoration of factor IIa or factor IIa activity is key for effective hemostasis. Limited evidence suggests that specific reversals for DOAC, e.g., idarucizumab for dabigatran and andexanet alfa for apixaban or rivaroxaban, might be superior to increasing thrombin generation by administration of prothrombin complex concentrates. To determinate, if DOAC reversal is indicated or not, time from last intake, anti-Xa/dTT values or results from POC tests can be considered. This experts' opinion provides a feasible decision algorithm for clinical practice.

Endothelial glycocalyx injury is involved in heatstroke-associated coagulopathy and protected by N-acetylcysteine

Introduction

Damage to endothelial glycocalyx (EGCX) can lead to coagulation disorders in sepsis. Heat stroke (HS) resembles sepsis in many aspects; however, it is unclear whether EGCX injury is involved in its pathophysiology. The purpose of this study was to examine the relationship between the damage of EGCX and the development of coagulation disorders during HS.

Methods

We retrospectively collected 159 HS patients and analyzed coagulation characteristics and prognosis of HS patients with or without disseminated intravascular coagulation (DIC). We also replicated a rat HS model and measured coagulation indexes, pulmonary capillary EGCX injury in HS rats. Finally, we evaluated the effect of the antioxidant N-acetylcysteine (NAC) on HS-initiated EGCX injury and coagulation disorders.

Results

Clinical data showed that HS patients complicated with DIC had a higher risk of death than HS patients without DIC. In a rat HS model, we found that rats subjected to heat stress developed hypercoagulability and platelet activation at the core body temperature of 43°C, just before the onset of HS. At 24 h of HS, the rats showed a consumptive hypo-coagulation state. The pulmonary capillary EGCX started to shed at 0 h of HS and became more severe at 24 h of HS. Importantly, pretreatment with NAC substantially alleviated EGCX damage and reversed the hypo-coagulation state in HS rats. Mechanically, HS initiated reactive oxidative species (ROS) generation, while ROS could directly cause EGCX damage. Critically, NAC protected against EGCX injury by attenuating ROS production in heat-stressed or hydrogen peroxide (H2O2)-stimulated endothelial cells.

Discussion

Our results indicate that the poor prognosis of HS patients correlates with severe coagulation disorders, coagulation abnormalities in HS rats are associated with the damage of EGCX, and NAC improves HS-induced coagulopathy, probably through its protection against EGCX injury by preventing ROS generation.

Effectiveness of Administration of Fibrinogen Concentrate as Prevention of Hypofibrinogenemia in Patients with Traumatic Brain Injury with a Higher Risk for Severe Hyperfibrinolysis: Single Center Before-and-After Study

BACKGROUND

Coagulopathy is often observed in severe traumatic brain injury (sTBI), and hyperfibrinolysis (HF) is associated with a poor prognosis. Although the efficacy of fibrinogen concentrate (FC) in multiple trauma has been reported, its efficacy in sTBI is unclear. Therefore, we delineated severe HF risk factors despite fresh frozen plasma transfusion. Using these risk factors, we defined high-risk patients and determined whether FC administration to this group improved fibrinogen level.

METHODS

In the first part of this study, successive adults with sTBI treated at our hospital between April 2016 and March 2019 were reviewed. Patients underwent transfusion as per our conventional protocol and were divided into two groups based on whether fibrinogen levels of ≥ 150 mg/dL were maintained 3-6 h after arrival to delineate the risk factors of severe HF. In the second part of the study, we conducted a before-and-after study in patients with sTBI who were at a higher risk for severe HF (presence of at least one of the risk factors identified in the first part of the study), comparing those treated with FC between April 2019 and March 2021 (FC group) with those treated with conventional transfusion before FC between April 2016 and March 2019. The primary outcome was maintenance of fibrinogen levels, and the secondary outcome was 30-day mortality.

RESULTS

In the first part of the study, 78 patients were included. Twenty-three patients did not maintain fibrinogen levels ≥ 150 mg/dL. A D-dimer level on arrival > 50 μg/mL, a fibrinogen level on arrival < 200 mg/dL, depressed skull fracture, and multiple trauma were severe HF risk factors. In the second part, compared with 46 patients who were identified as being at high risk for severe HF but were not administered FC (non-FC group), fibrinogen levels ≥ 150 mg/dL 3-6 h after arrival were maintained in 14 of 15 patients in the FC group (odds ratio: 0.07; 95% confidence interval: 0.01-0.59). Although there were significant differences in fibrinogen levels, no significant differences were observed in terms of 30-day mortality between the groups.

CONCLUSIONS

Coagulation abnormalities on arrival, severe skull fracture, and multiple trauma are severe HF risk factors. FC administration may contribute to rapid correction of developing hypofibrinogenemia.

A Case of Multifocal Lymphangioendotheliomatosis With Thrombocytopenia and Changes in Coagulopathy

Multifocal lymphangioendotheliomatosis with thrombocytopenia is a rare disease characterized by progressive multiple vascular lesions and is accompanied by thrombocytopenia. The precise diagnosis of this disease is frequently difficult because of the heterogeneity of the clinical symptoms. We report a case of a male infant who presented with severe thrombocytopenia induced by local inflammation. In addition, enlargement of the extremities with soft tissue and bone involvement without gastrointestinal bleeding was observed. The thrombocytopenia resolved after a combination therapy of sirolimus and prednisolone. Our finding that plasma angiopoietin-2 concentrations reflected the disease status suggests its utility as a biomarker of Multifocal lymphangioendotheliomatosis with thrombocytopenia.

Dabigatran etexilate is efficacious in consumptive coagulopathy and pain associated with venous malformations

OBJECTIVE

Consumptive coagulopathy treatment and pain management are crucial for patients with venous malformations (VMs). Dabigatran etexilate, a non-vitamin K antagonist oral anticoagulant, has known advantages compared with low-molecular-weight heparin and vitamin K antagonists, including oral administration, a more consistent pharmacokinetics/pharmacodynamics profile, a better safety profile, and no need for coagulation surveillance. In the present study, we tested the efficacy and safety of dabigatran etexilate for consumptive coagulopathy treatment and pain management for patients with VMs.

METHODS

To investigate the efficacy and safety of dabigatran etexilate in treating localized intravascular coagulation (LIC) associated with VM, we retrospectively collected data for 19 outpatients with VM and LIC, who had been treated with dabigatran etexilate from September 2019 to June 2021. The patients provided oral informed consent and underwent biologic blood testing, routine examinations, and determination of coagulation function before and after treatment. The dosage of dabigatran etexilate was 110 mg twice daily for adults and 55 mg twice daily for children.

RESULTS

All 19 patients had benefited from dabigatran etexilate treatment with coagulation improvement and pain relief. Pain had improved in all 16 evaluable patients. The fibrinogen and D-dimer levels had improved in 18 of 19 patients. The fibrin degradation product level had improved in 10 of 14 patients. None of patients reported lesion regression, appearance changes, or improvement in mobility. No significant differences were found in the D-dimer, fibrinogen, and fibrin degradation product levels between the short-term (<10 days) and long-term (≥10 days) use of the medication. Dabigatran etexilate was well tolerated by all patients. No bleeding event had occurred during follow-up.

CONCLUSIONS

The results of our study have confirmed the efficacy and safety of dabigatran etexilate in treating pain and LIC in patients with VMs. Dabigatran etexilate is a suitable choice preoperatively to modify coagulation function and pain in patients with VMs.

Communication from the Scientific and Standardization Committee of the International Society on Thrombosis and Haemostasis on sepsis-induced coagulopathy in the management of sepsis

Disseminated intravascular coagulation (DIC) is a life-threatening complication in sepsis and other critical conditions. The International Society on Thrombosis and Haemostasis (ISTH) released the diagnostic criteria for overt DIC in 2001. Since then, ISTH overt DIC has been used as the global standard criterion for a decompensated stage of DIC. Because detecting an earlier stage of DIC would be useful for therapeutic considerations, the scientific standardization committees of the ISTH introduced the sepsis-induced coagulopathy (SIC) scoring system in 2019. The SIC scoring system is specifically designed to detect the compensated phase of DIC in sepsis, which can lead to overt DIC with disease progression. Studies examining the performance of the SIC scoring system have reported its usefulness over the past 5 years. The reported incidence of SIC was approximately 60% in patients with sepsis, which was twice as much as that of overt DIC. Almost all patients with overt DIC were diagnosed with SIC earlier. The reported mortality of SIC was ≥30% and, thus, can be used for patient selection for anticoagulant therapy. Despite the limited data, some continue to suggest the potential efficacy of anticoagulant therapy in patients with SIC. Although heparin, antithrombin, and thrombomodulin are the candidates for anticoagulation, none of them have proven to be effective with robust evidence, and future trials are warranted.

Outcomes of 4-factor Prothrombin Complex Concentrate in Patients With Liver Disease and Nonvitamin K Antagonist-Related Coagulopathy: A Retrospective Study

The administration of 4-factor prothrombin complex concentrate (4F-PCC) has expanded beyond its Food and Drug Administration (FDA)-approved indication for the emergent reversal of vitamin K antagonists (VKAs). Therefore, this study aimed to evaluate the risks and benefits associated with the expanded use of 4F-PCC. We conducted a single-center retrospective review of 4F-PCC administrations at our university hospital. Of the 159 patients who received 4F-PCC, 76% (n = 121) and 24% (n = 38) received it for the FDA-approved indication in the vitamin K-related coagulopathy (VKA) group and for expanded use in the nonvitamin K-related coagulopathy (nVKA) group, respectively. The expanded use of 4F-PCC was associated with a less robust reduction in the international normalized ratio (INR) (INR of -0.7 ± 1.3 vs INR of -1.6 ± 1.8, P = .002), and fewer patients in the nVKA group achieved a postadministration INR of less than1.5 (11% vs 79%, P = .001) than those in the VKA group. Furthermore, the 30-day mortality rate was significantly higher in the nVKA cohort than in the VKA cohort (42% vs 20%, P = .04). Notably, based on our data, underlying differences in the patient's comorbidities, particularly advanced liver disease, may have contributed to the observed outcome variations, including mortality rate. Therefore, factors, including comorbidities and the underlying etiology of coagulopathy, should be considered when deciding on the expanded use of 4F-PCC. Further research is needed to better understand the potential risks and benefits of 4F-PCC in expanded use scenarios, and the clinical decision to use 4F-PCC outside its FDA-approved indication should be made carefully, considering this information.

The risk factors for coagulation disorder of chimeric antigen receptor-T cell therapy in patients with hematological tumors: A systematic review and meta-analysis

BACKGROUND

Currently, the frequency of coagulation dysfunction associated with chimeric antigen receptor-T cell (Car-T) therapy cannot yet be determined.

OBJECTIVE

We performed a systematic review and meta-analysis to examine the prevalence of abnormal laboratory tests related to coagulation disorders in patients receiving Car-T therapy and provide a reference for future risk assessment mechanisms.

METHODS

We searched PubMed, Embase, and Web of Science for relevant studies and evaluated their quality using the methodology index of non-random research (MINORS). 2672 quotations were retrieved via systematic searches. After screening of titles, abstracts and full-text, 45 trials involving 2541 patients were ultimately included. 41 studies reported the incidence of thrombocytopenia, 8 studies reported the rate of low fibrin, 4 trials reported the rate of APTT or PT abnormalities and only 3 trials reported the incidence of venous thromboembolism (VTE). We performed a quantitative meta-analysis to explore the incidence of thrombocytopenia following Car-T treatment. The incidence of hypofibrinogenemia, VTE, and abnormal APTT or PT was only qualitatively assessed, as fewer reports were included in this study.

RESULTS

The overall incidence of thrombocytopenia associated with Car-T therapy was 45.8% (95%[CI], 0.384-0.533). The highest rates of thrombocytopenia occurred in patients with multiple myeloma (60.1%, 95%[CI], 0.507-0.688) and aged between 18 to 60 (50%, 95%[CI], 0.367-0.633). There was greater prevalence of thrombocytopenia in BCMA-Car-T therapy of 58.7% (95%[CI], 0.482-0.685). Thrombocytopenia occurred most frequently in Car-T patients treated with a dosage of 1 × 105-1 × 106 cell/kg, at a rate of 66.2% (95%[CI], 0.561-0.749).

CONCLUSION

Overall, 45.8 percent of patients receiving Car-T treatment suffered from thrombocytopenia. Multiple myeloma patients, ages between 18-60, a dose of 1 × 105-1 × 106 cell/kg and BCMA-Car-T therapy are all considered high-risk factors.

Association between Pre-Existing Long-Term β-Blocker Therapy and the Outcomes of Sepsis-Associated Coagulopathy: A Retrospective Study

Background and Objectives: Previous studies have suggested that long-term β-blocker therapy before sepsis is associated with reduced mortality. Sepsis-associated coagulopathy (SAC) remains a common complication in patients with sepsis and is associated with increased mortality. Adrenergic pathways are involved in the regulation of the coagulation system. Pre-existing long-term β-blocker therapy may have potentially beneficial effects on SAC and has yet to be well characterized. We aimed to assess the potential association between pre-existing long-term β-blocker therapy and the outcomes of patients with SAC. Materials and Methods: This study retrospectively screened the clinical data of adult patients with SAC admitted to the Intensive Care Unit (ICU) and respiratory ICU between May 2020 and October 2022. Patients with SAC who took any β-blocker for at least one year were considered pre-existing long-term β-blocker therapy. All enrolled patients were followed up for 28 days or until death. Results: Among the 228 SAC patients, 48 received long-term β-blocker therapy before septic episodes. Pre-existing long-term β-blocker therapy was associated with reduced vasopressor requirements and a decreased 28-day mortality (log-rank test: p = 0.041). In particular, long-term β-blocker therapy was related to substantially lower D-dimer levels and a trend of improved activated partial thromboplastin time in patients with SAC during initial ICU admission. Multivariable regression analysis showed that long-term β-blocker therapy was significantly and independently associated with a 28-day mortality among patients with SAC (adjusted odds ratio, 0.55; 95% confidence interval, (0.32-0.94); p = 0.030). Conclusions: Pre-existing long-term β-blocker therapy might be associated with reduced vasopressor requirements and a decreased 28-day mortality among patients with SAC, providing evidence for the protective effect of β-blockers against SAC in managing sepsis.

Management Practices for Asparaginase-associated Coagulopathy: A Survey of Pediatric Oncologists

BACKGROUND

Coagulopathy and thrombosis are well-described complications of asparaginase therapy. However, treatment practices in pediatric hematology/oncology (PHO) patients vary widely as evidence-based guidelines for clinical management of these complications in this population are lacking.

OBJECTIVE

The objective of this study was to assess management practices of asparaginase-related coagulopathy by pediatric hematologist/oncologist attending physicians.

DESIGN/METHOD

Email survey sent to 2327 PHO physicians primarily practicing in the United States.

RESULTS

Two hundred eighty-five (12.2%) attending physicians completed the survey. Only 4.6% (n=13/285) routinely prescribe prophylactic anticoagulation during induction chemotherapy for leukemia. Slightly more than half (n=145/250, 50.9%) of all providers perform baseline coagulation studies. Most providers that were surveyed (n=185/285, 64.9%) only replete coagulant factors if the patient experiences bleeding or bruising. One hundred thirty (n=130/285, 45.6%) physicians replace low fibrinogen. The median fibrinogen replacement was 100 mg/dL (range: 40 to 200 mg/dL) with the median target of at least 100 mg/dL (range: 50 to 200 mg/dL). A minority of physicians (n=39/250, 13.7%) replace low antithrombin. The median antithrombin cutoff activity level was 60% (range: 40% to 100%) with a median target of 75% (range: 40% to 125%).

CONCLUSIONS

There is a significant variation in PHO physician practices for monitoring and management of asparaginase-associated hemostatic derangements. Evidence-based guidelines have the potential to standardize practices.

Safety of Vitamin K in mechanical heart valve patients with supratherapeutic INR: A systematic review and meta-analysis

BACKGROUND

Patients who had mechanical heart valves and an international normalized ratio (INR) of >5.0 should be managed by temporary cessation of vitamin K antagonist. This study aimed to investigate the safety of low-dose vitamin K1 in patients with mechanical heart valves who have supratherapeutic INR.

METHODS

CINAHL, Cochran Library, Clinical trial.gov, OpenGrey, PubMed, ScienceDirect, and Scopus were systematically searched from the inception up to October 2021 without language restriction. Studies comparing the safety of low-dose vitamin K1 treatment in patients with placebo or other anticoagulant reversal agents were included. We used a random-effect model for the meta-analysis. Publication bias was determined by a funnel plot with subsequent Begg's test and Egger's test.

RESULTS

From 7529 retrieved studies, 3 randomized control trials were included in the meta-analysis. Pooled data demonstrated that low-dose vitamin K was not associated with thromboembolism rate (risk ratio [RR] = 0.94; 95% CI: 0.19-4.55) major bleeding rate (RR = 0.58; 95% CI: 0.07-4.82), and minor bleeding rate (RR = 0.60; 95% CI: 0.07-5.09). Subgroup and sensitivity analysis demonstrated the nonsignificant effect of low-dose vitamin K on the risk of thromboembolism. Publication bias was not apparent, according to Begg's test and Egger's test (P = .090 and 0.134, respectively).

CONCLUSION

The current evidence does not support the role of low-dose vitamin K as a trigger of thromboembolism in supratherapeutic INR patients with mechanical heart valves. Nevertheless, more well-designed studies with larger sample sizes are required to justify this research question.

Assessment of need for hemostatic evaluation in patients taking valproic acid: A retrospective cross-sectional study

INTRODUCTION

Valproic acid (VPA) is a frequently prescribed anti-epileptic drug. Since its introduction side effects on hemostasis are reported. However, studies show conflicting results, and the clinical relevance is questioned. We aimed to determine the coagulopathies induced by VPA in patients who undergo high-risk surgery. The study results warrant attention to this issue, which might contribute to reducing bleeding complications in future patients.

METHODS

Between January 2012 and August 2020, 73 consecutive patients using VPA were retrospectively included. Extensive laboratory hemostatic assessment (including platelet function tests) was performed before elective high-risk surgery. Patient characteristics, details of VPA treatment, and laboratory results were extracted from medical records.

RESULTS

46.6% of the patients using VPA (n = 73) showed coagulopathy. Mainly, platelet function disorder was found (36.4%). Thrombocytopenia was seen in 9.6% of the patients. Data suggested that the incidence of coagulopathies was almost twice as high in children as compared to adults and hypofibrinogenemia was only demonstrated in children. No association was found between the incidence of coagulopathies and VPA dosage (mg/kg/day).

CONCLUSION

A considerable number of patients using VPA were diagnosed with coagulopathy, especially platelet function disorder. Further prospective studies are needed to confirm the need for comprehensive laboratory testing before elective high-risk surgery in these patients.

Personalized modulation of coagulation factors using a thrombin dynamics model to treat trauma-induced coagulopathy

Current trauma-induced coagulopathy resuscitation protocols use slow laboratory measurements, rules-of-thumb, and clinician gestalt to administer large volumes of uncharacterized, non-tailored blood products. These one-size-fits-all treatment approaches have high mortality. Here, we provide significant evidence that trauma patient survival 24 h after hospital admission occurs if and only if blood protein coagulation factor concentrations equilibrate at a normal value, either from inadvertent plasma-based modulation or from innate compensation. This result motivates quantitatively guiding trauma patient coagulation factor levels while accounting for protein interactions. Toward such treatment, we develop a Goal-oriented Coagulation Management (GCM) algorithm, a personalized and automated ordered sequence of operations to compute and specify coagulation factor concentrations that rectify clotting. This novel GCM algorithm also integrates new control-oriented advancements that we make in this work: an improvement of a prior thrombin dynamics model that captures the coagulation process to control, a use of rapidly-measurable concentrations to help predict patient state, and an accounting of patient-specific effects and limitations when adding coagulation factors to remedy coagulopathy. Validation of the GCM algorithm's guidance shows superior performance over clinical practice in attaining normal coagulation factor concentrations and normal clotting profiles simultaneously.

Beneficial Properties of Bromelain

Bromelain is a major sulfhydryl proteolytic enzyme found in pineapple plants, having multiple activities in many areas of medicine. Due to its low toxicity, high efficiency, high availability, and relative simplicity of acquisition, it is the object of inexhaustible interest of scientists. This review summarizes scientific reports concerning the possible application of bromelain in treating cardiovascular diseases, blood coagulation and fibrinolysis disorders, infectious diseases, inflammation-associated diseases, and many types of cancer. However, for the proper application of such multi-action activities of bromelain, further exploration of the mechanism of its action is needed. It is supposed that the anti-viral, anti-inflammatory, cardioprotective and anti-coagulatory activity of bromelain may become a complementary therapy for COVID-19 and post-COVID-19 patients. During the irrepressible spread of novel variants of the SARS-CoV-2 virus, such beneficial properties of this biomolecule might help prevent escalation and the progression of the COVID-19 disease.

Ultramicronized Palmitoylethanolamide in the Management of Sepsis-Induced Coagulopathy and Disseminated Intravascular Coagulation

Disseminated intravascular coagulation (DIC) is a severe condition characterized by the systemic formation of microthrombi complicated with bleeding tendency and organ dysfunction. In the last years, it represents one of the most frequent consequences of coronavirus disease 2019 (COVID-19). The pathogenesis of DIC is complex, with cross-talk between the coagulant and inflammatory pathways. The objective of this study is to investigate the anti-inflammatory action of ultramicronized palmitoylethanolamide (um-PEA) in a lipopolysaccharide (LPS)-induced DIC model in rats. Experimental DIC was induced by continual infusion of LPS (30 mg/kg) for 4 h through the tail vein. Um-PEA (30 mg/kg) was given orally 30 min before and 1 h after the start of intravenous infusion of LPS. Results showed that um-PEA reduced alteration of coagulation markers, as well as proinflammatory cytokine release in plasma and lung samples, induced by LPS infusion. Furthermore, um-PEA also has the effect of preventing the formation of fibrin deposition and lung damage. Moreover, um-PEA was able to reduce the number of mast cells (MCs) and the release of its serine proteases, which are also necessary for SARS-CoV-2 infection. These results suggest that um-PEA could be considered as a potential therapeutic approach in the management of DIC and in clinical implications associated to coagulopathy and lung dysfunction, such as COVID-19.

Bleeding and Thrombosis: Insights into Pathophysiology of Bothrops Venom-Related Hemostasis Disorders

Toxins from Bothrops venoms targeting hemostasis are responsible for a broad range of clinical and biological syndromes including local and systemic bleeding, incoagulability, thrombotic microangiopathy and macrothrombosis. Beyond hemostais disorders, toxins are also involved in the pathogenesis of edema and in most complications such as hypovolemia, cardiovascular collapse, acute kidney injury, myonecrosis, compartmental syndrome and superinfection. These toxins can be classified as enzymatic proteins (snake venom metalloproteinases, snake venom serine proteases, phospholipases A₂ and L-amino acid oxidases) and non-enzymatic proteins (desintegrins and C-type lectin proteins). Bleeding is due to a multifocal toxicity targeting vessels, platelets and coagulation factors. Vessel damage due to the degradation of basement membrane and the subsequent disruption of endothelial cell integrity under hydrostatic pressure and tangential shear stress is primarily responsible for bleeding. Hemorrhage is promoted by thrombocytopenia, platelet hypoaggregation, consumption coagulopathy and fibrin(ogen)olysis. Onset of thrombotic microangiopathy is probably due to the switch of endothelium to a prothrombotic phenotype with overexpression of tissue factor and other pro-aggregating biomarkers in association with activation of platelets and coagulation. Thrombosis involving large-caliber vessels in B. lanceolatus envenomation remains a unique entity, which exact pathophysiology remains poorly understood.

Protocol for a multicentre, randomised, parallel-control, superiority trial comparing administration of clotting factor concentrates with a standard massive haemorrhage protocol in severely bleeding trauma patients: the FiiRST 2 trial (a 2020 EAST multicentre trial)

INTRODUCTION

Acute traumatic coagulopathy (ATC) in bleeding trauma patients increase in-hospital mortality. Fibrinogen concentrate (FC) and prothrombin complex concentrate (PCC) are two purified concentrates of clotting factors that have been used to treat ATC. However, there is a knowledge gap on their use compared with the standard of care, the transfusion of plasma.

METHODS AND ANALYSIS

The factors in the initial resuscitation of severe trauma 2 trial is a multicentre, randomised, parallel-control, single-blinded, phase IV superiority trial. The study aims to address efficacy and safety of the early use of FC and PCC compared with a plasma-based resuscitation. Adult trauma patients requiring massive haemorrhage protocol activation on hospital arrival will receive FC 4 g and PCC 2000 IU or plasma 4 U, based on random allocation. The primary outcome is a composite of the cumulative number of all units of red cells, plasma and platelets transfused within 24 hours following admission. Secondary outcomes include measures of efficacy and safety of the intervention. Enrolment of 350 patients will provide an initial power >80% to demonstrate superiority for the primary outcome. After enrolment of 120 patients, a preplanned adaptive interim analysis will be conducted to reassess assumptions, check for early superiority demonstration or reassess the sample size for remainder of the study.

ETHICS AND DISSEMINATION

The study has been approved by local and provincial research ethics boards and will be conducted according to the Declaration of Helsinki, Good Clinical Practice guidelines and regulatory requirements. As per the Tri-Council Policy Statement, patient consent will be deferred due to the emergency nature of the interventions. If superiority is established, results will have a major impact on clinical practice by reducing exposure to non-virally inactivated blood products, shortening the time for administration of clotting factors, correct coagulopathy more efficaciously and reduce the reliance on AB plasma.

TRIAL REGISTRATION NUMBER

NCT04534751, pre results.

COVID-19-related coagulopathy: A review of pathophysiology and pharmaceutical management

December 2019 will never be forgotten in the history of medicine when an outbreak of pneumonia of unknown etiology in Wuhan, China sooner or later prompted the World Health Organization to issue a public health warning emergency. This is not the first nor will it be the last time that a member of β-coronaviruses (CoVs) is waging a full-scale war against human health. Notwithstanding the fact that pneumonia is the primary symptom of the novel coronavirus (2019nCoV; designated as SARS-CoV-2), the emergence of severe disease mainly due to the injury of nonpulmonary organs at the shadow of coagulopathy leaves no choice, in some cases, rather than a dreadful death. Multiple casual factors such as inflammation, endothelial dysfunction, platelet and complement activation, renin-angiotensin-aldosterone system derangement, and hypoxemia play a major role in the pathogenesis of coagulopathy in coronavirus disease 2019 (COVID-19) patients. Due to the undeniable role of coagulation dysfunction in the initiation of several complications, assessment of coagulation parameters and the platelet count would be beneficial in early diagnosis and also timely prediction of disease severity. Although low-molecular-weight heparin is considered as the first-line of treatment in COVID-19-associated coagulopathy, several possible therapeutic options have also been proposed for better management of the disease. In conclusion, this review would help us to gain insight into the pathogenesis, clinical manifestation, and laboratory findings associated with COVID-19 coagulopathy and would summarize management strategies to alleviate coagulopathy-related complications.

Altered platelet and coagulation function in moderate-to-severe COVID-19

To reveal if coagulopathies relate to the course of COVID-19, we examined 255 patients with moderate and severe COVID-19, receiving anticoagulants and immunosuppressive drugs. Coagulopathy manifested predominantly as hypercoagulability that correlated directly with systemic inflammation, disease severity, comorbidities, and mortality risk. The prolonged clotting tests in about ¼ of cases were associated with high levels of C-reactive protein and antiphospholipid antibodies, which impeded coagulation in vitro. Contraction of blood clots was hindered in about ½ of patients, especially in severe and fatal cases, and correlated directly with prothrombotic parameters. A decrease in platelet contractility was due to moderate thrombocytopenia in combination with platelet dysfunction. Clots with impaired contraction were porous, had a low content of compressed polyhedral erythrocytes (polyhedrocytes) and an even distribution of fibrin, suggesting that the uncompacted intravital clots are more obstructive but patients could also be prone to bleeding. The absence of consumption coagulopathy suggests the predominance of local and/or regional microthrombosis rather than disseminated intravascular coagulation. The results obtained (i) confirm the importance of hemostatic disorders in COVID-19 and their relation to systemic inflammation; (ii) justify monitoring of hemostasis, including the kinetics of blood clot contraction; (iii) substantiate the active prophylaxis of thrombotic complications in COVID-19.

Pathology-specific experimental antivenoms for haemotoxic snakebite: The impact of immunogen diversity on the in vitro cross-reactivity and in vivo neutralisation of geographically diverse snake venoms

BACKGROUND

Snakebite is a neglected tropical disease that causes high global rates of mortality and morbidity. Although snakebite can cause a variety of pathologies in victims, haemotoxic effects are particularly common and are typically characterised by haemorrhage and/or venom-induced consumption coagulopathy. Antivenoms are the mainstay therapeutic for treating the toxic effects of snakebite, but despite saving thousands of lives annually, these therapies are associated with limited cross-snake species efficacy due to venom variation, which ultimately restricts their therapeutic utility to particular geographical regions.

METHODOLOGY/PRINCIPAL FINDINGS

In this study we explored the feasibility of generating globally effective pathology-specific antivenoms to counteract the haemotoxic signs of snakebite envenoming. Two different immunogen mixtures, consisting of seven and twelve haemotoxic venoms sourced from geographically diverse and/or medically important snakes, were used to raise ovine polyclonal antibodies, prior to characterisation of their immunological binding characteristics and in vitro neutralisation profiles against each of the venoms. Despite variability of the immunogen mixtures, both experimental antivenoms exhibited broadly comparable in vitro venom binding and neutralisation profiles against the individual venom immunogens in immunological and functional assays. However, in vivo assessments using a murine preclinical model of antivenom efficacy revealed substantial differences in venom neutralisation. The experimental antivenom generated from the seven venom immunogen mixture outperformed the comparator, by providing protective effects against venom lethality caused by seven of the eight geographically diverse venoms tested, including three distinct venoms that were not used as immunogens to generate this antivenom. These findings suggest that a core set of venom immunogens may be sufficient to stimulate antibodies capable of broadly neutralising a geographically diverse array of haemotoxic snake venoms, and that adding additional venom immunogens may impact negatively on the dose efficacy of the resulting antivenom.

CONCLUSIONS/SIGNIFICANCE

Although selection of appropriate immunogens that encapsulate venom toxin diversity without diluting antivenom potency remains challenging and further optimisation is required, the findings from this pilot study suggest that the generation of pathology-specific antivenoms with global utility is likely to feasible, thereby highlighting their promise as future modular treatments for the world's tropical snakebite victims.

[Treatment of sepsis-induced coagulopathy : Results of a Germany-wide survey in intensive care units]

BACKGROUND

In the context of sepsis and septic shock, coagulopathy often occurs due to the close relationship between coagulation and inflammation. Sepsis-induced coagulopathy (SIC) is the most severe and potentially fatal form. Anticoagulants used in prophylactic or therapeutic doses are discussed to potentially exert beneficial effects in patients with sepsis and/or SIC; however, due to the lack of evidence recent guidelines are limited to recommendations for drug prophylaxis of venous thromboembolism (VTE), while treatment of SIC has not been addressed.

METHODS

In order to determine the status quo of VTE prophylaxis as well as treatment of SIC in German intensive care units (ICU), we conducted a Germany-wide online survey among heads of ICUs from October 2019 to May 2020. In April 2020, the survey was supplemented by an additional block of questions on VTE prophylaxis and SIC treatment in coronavirus disease 2019 (COVID-19) patients.

RESULTS

A total of 67 senior doctors took part in the survey. The majority (n = 50; 74.6%) of the responses were from ICU under the direction of an anesthesiologist and/or a department of anesthesiology. Most of the participants worked either at a university hospital (n = 31; 47.8%) or an academic teaching hospital (n = 27; 40.3%). The survey results show a pronounced heterogeneity in clinical practice with respect to the prophylaxis of VTE as well as SIC treatment. In an exemplary case of pneumogenic sepsis, low molecular weight heparins (LMWH) were by far the most frequently mentioned group of medications (n = 51; 76.1% of the responding ITS). In the majority of cases (n = 43; 64.2%), anti-FXa activity is not monitored with the use of LMWH in prophylaxis doses. Unfractionated heparin (UFH) was listed as a strategy for VTE prophylaxis in 37.3% of the responses (n = 25). In an exemplary case of abdominal sepsis 54.5% of the participants (n = 36; multiple answers possible) stated the use of UFH or LMWH and UFH with dosage controlled by PTT is used on two participating ICUs. The anti-FXa activity under prophylactic anticoagulation with LMWH is monitored in 7 participating clinics (10.6%) in abdominal sepsis. Systematic screening for sepsis-associated coagulation disorders does not take place in most hospitals and patterns in the use of anticoagulants show significant variability between ICUs. In the case of COVID-19 patients, it is particularly noticeable that in three quarters of the participating ICUs the practice of drug-based VTE prophylaxis and SIC treatment does not differ from that of non-COVID-19 patients.

CONCLUSION

The heterogeneity of answers collected in the survey suggests that a systematic approach to this topic via clinical trials is urgently needed to underline individualized patient care with the necessary evidence.

Accuracy and Safety of 1,055 Transjugular Liver Biopsies in Postliver Transplant Patients

INTRODUCTION

The purpose of this study was to investigate the rates of complications and diagnostic yield of transjugular liver biopsy (TJLB) in deceased donor liver transplant (DDLT) recipients.

METHODS

From January 2009 to December 2019, 1,055 TJLBs were performed in 603 adult DDLT recipients with a mean age of 54 (±12 years). Data were retrospectively reviewed to determine the diagnostic efficacy and incidence of major and minor complications in the 3-day and 1-month period after TJLB. In addition, data were stratified according to platelet count and international normalized ratio to determine the safety of TJLB in patients with varying degrees of coagulopathy.

RESULTS

TJLB yielded diagnostic rate of 98.1% (1,035/1,055), with an overall complication rate of 8.3% (88/1,055). Major complications accounted for 0.85% (9/1,055), and minor complications occurred in 7.48% (79/1,055). When patients were stratified by platelet count (0-50, 51-100, 101-200, 201-300, and >300 × 103 platelets/μL), no significant difference was noted in complication rates (9.5%, 8.6%, 7.6%, 8.5%, and 10.7%, respectively). When grouped by international normalized ratio (0-1, 1.1-2.0, 2.1-3.0, and >3.0), there was no statistical difference in complication rates (8.3%, 8.5%, 7.7%, and 0%, respectively).

DISCUSSION

TJLB is a safe, adequate, and effective method to investigate hepatic disorders in DDLT recipients with severe coagulopathy.

Thrombosis, Bleeding, and the Observational Effect of Early Therapeutic Anticoagulation on Survival in Critically Ill Patients With COVID-19

BACKGROUND

Hypercoagulability may be a key mechanism of death in patients with coronavirus disease 2019 (COVID-19).

OBJECTIVE

To evaluate the incidence of venous thromboembolism (VTE) and major bleeding in critically ill patients with COVID-19 and examine the observational effect of early therapeutic anticoagulation on survival.

DESIGN

In a multicenter cohort study of 3239 critically ill adults with COVID-19, the incidence of VTE and major bleeding within 14 days after intensive care unit (ICU) admission was evaluated. A target trial emulation in which patients were categorized according to receipt or no receipt of therapeutic anticoagulation in the first 2 days of ICU admission was done to examine the observational effect of early therapeutic anticoagulation on survival. A Cox model with inverse probability weighting to adjust for confounding was used.

SETTING

67 hospitals in the United States.

PARTICIPANTS

Adults with COVID-19 admitted to a participating ICU.

MEASUREMENTS

Time to death, censored at hospital discharge, or date of last follow-up.

RESULTS

Among the 3239 patients included, the median age was 61 years (interquartile range, 53 to 71 years), and 2088 (64.5%) were men. A total of 204 patients (6.3%) developed VTE, and 90 patients (2.8%) developed a major bleeding event. Independent predictors of VTE were male sex and higher D-dimer level on ICU admission. Among the 2809 patients included in the target trial emulation, 384 (11.9%) received early therapeutic anticoagulation. In the primary analysis, during a median follow-up of 27 days, patients who received early therapeutic anticoagulation had a similar risk for death as those who did not (hazard ratio, 1.12 [95% CI, 0.92 to 1.35]).

LIMITATION

Observational design.

CONCLUSION

Among critically ill adults with COVID-19, early therapeutic anticoagulation did not affect survival in the target trial emulation.

PRIMARY FUNDING SOURCE

None.

Unintentional ingestion of a high dose of acenocoumarol in a young child

Acute intoxication with a vitamin K antagonist may cause serious coagulopathy. We report the accidental ingestion of a high dose of acenocoumarol in a young child. Two intravenous administrations of 5 mg of vitamin K, in combination with fast and repeated administration of activated charcoal and sodium sulfate, were sufficient to prevent coagulopathy and related symptoms, despite a confirmed elevated blood acenocoumarol concentration (260 µg/L).

[Tranexamic acid: widely applicable, few risks]

Tranexamic acid is a cheap and easy to use drug for the treatment and prevention of bleeding. In the past, its use was mainly empiric and primarily in patients with coagulation disorders. More recently, large scale randomized controlled trials have shown that tranexamic acid reduces mortality in women with postpartum hemorrhage and in victims of trauma. In a number of surgical settings, including cardiothoracic and orthopedic, tranexamic acid reduces bleeding complications. In these studies, there was no signal of increased risk of thrombosis. Tranexamic acid is also effective in reducing heavy menstrual bleeding, the prevention of bleeding after dental interventions and a number of other high-prevalence conditions. There are no data that support an increased risk of thrombosis when patients without haemostatic disorders use tranexamic acid for a longer period, but addition studies would be helpful. Finally, the topical administration of the drug for mucocutaneous nuisance bleeds deserves more attention.

The relationship between cardiac injury, inflammation and coagulation in predicting COVID-19 outcome

High sensitivity troponin T (hsTnT) is a strong predictor of adverse outcome during SARS-CoV-2 infection. However, its determinants remain partially unknown. We aimed to assess the relationship between severity of inflammatory response/coagulation abnormalities and hsTnT in Coronavirus Disease 2019 (COVID-19). We then explored the relevance of these pathways in defining mortality and complications risk and the potential effects of the treatments to attenuate such risk. In this single-center, prospective, observational study we enrolled 266 consecutive patients hospitalized for SARS-CoV-2 pneumonia. Primary endpoint was in-hospital COVID-19 mortality. hsTnT, even after adjustment for confounders, was associated with mortality. D-dimer and CRP presented stronger associations with hsTnT than PaO2. Changes of hsTnT, D-dimer and CRP were related; but only D-dimer was associated with mortality. Moreover, low molecular weight heparin showed attenuation of the mortality in the whole population, particularly in subjects with higher hsTnT. D-dimer possessed a strong relationship with hsTnT and mortality. Anticoagulation treatment showed greater benefits with regard to mortality. These findings suggest a major role of SARS-CoV-2 coagulopathy in hsTnT elevation and its related mortality in COVID-19. A better understanding of the mechanisms related to COVID-19 might pave the way to therapy tailoring in these high-risk individuals.

Thrombocytopathy and endotheliopathy: crucial contributors to COVID-19 thromboinflammation

The core pathology of coronavirus disease 2019 (COVID-19) is infection of airway cells by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that results in excessive inflammation and respiratory disease, with cytokine storm and acute respiratory distress syndrome implicated in the most severe cases. Thrombotic complications are a major cause of morbidity and mortality in patients with COVID-19. Patients with pre-existing cardiovascular disease and/or traditional cardiovascular risk factors, including obesity, diabetes mellitus, hypertension and advanced age, are at the highest risk of death from COVID-19. In this Review, we summarize new lines of evidence that point to both platelet and endothelial dysfunction as essential components of COVID-19 pathology and describe the mechanisms that might account for the contribution of cardiovascular risk factors to the most severe outcomes in COVID-19. We highlight the distinct contributions of coagulopathy, thrombocytopathy and endotheliopathy to the pathogenesis of COVID-19 and discuss potential therapeutic strategies in the management of patients with COVD-19. Harnessing the expertise of the biomedical and clinical communities is imperative to expand the available therapeutics beyond anticoagulants and to target both thrombocytopathy and endotheliopathy. Only with such collaborative efforts can we better prepare for further waves and for future coronavirus-related pandemics.

SARS-COV-2-associated coagulopathy and thromboembolism prophylaxis in children: A single-center observational study

BACKGROUND

Multiple investigators have described an increased incidence of thromboembolic events in SARS-CoV-2-infected individuals. Data concerning hemostatic complications in children hospitalized for COVID-19/multisystem inflammatory syndrome in children (MIS-C) are scant.

OBJECTIVES

To share our experience in managing SARS-CoV-2-associated pro-coagulant state in hospitalized children.

METHODS

D-dimer values were recorded at diagnosis in children hospitalized for SARS-CoV-2-related manifestations. In moderately to critically ill patients and MIS-C cases, coagulation and inflammatory markers were checked at multiple time points and median results were compared. Pro-thrombotic risk factors were appraised for each child and thromboprophylaxis was started in selected cases.

RESULTS

Thirty-five patients were prospectively enrolled. D-dimer values did not discriminate COVID-19 of differing severity, whereas were markedly different between the COVID-19 and the MIS-C cohorts. In both cohorts, D-dimer and C-reactive protein levels increased upon clinical worsening but were not accompanied by decreased fibrinogen or platelet values, with all parameters returning to normal upon disease resolution. Six patients had multiple thrombotic risk factors and were started on pharmacological thromboprophylaxis. No deaths or thrombotic or bleeding complications occurred.

CONCLUSIONS

COVID-19 pediatric patients show mildly altered coagulation and inflammatory parameters; on the other hand, MIS-C cases showed laboratory signs of an inflammatory driven pro-coagulant status. Universal anticoagulant prophylaxis in hospitalized children with SARS-CoV-2-related manifestations is not warranted, but may be offered to patients with other pro-thrombotic risk factors in the context of a multi-modal therapeutic approach.

COVID-19 Coagulopathy: Current knowledge and guidelines on anticoagulation

COVID-19-associated coagulopathy (CAC) is a feature of COVID-19 that can lead to various thrombotic complications and death. In this review, we briefly highlight possible etiologies, including direct cytotoxicity caused by the SARS-CoV-2 virus, and the activation of proinflammatory molecules such as cytokines, underlying coagulopathy. Endothelial dysfunction has been highlighted as pivotal, irrespective of the mechanism involved in CAC. Specific features of CAC distinguishing it from disseminated intravascular coagulopathy and sepsis or ARDS-associated coagulopathy have been discussed. We have also highlighted some hematological parameters, such as elevated d-dimers and partial prothrombin and prothrombin times prolongation, which can guide the use of anticoagulation in critically ill patients. We conclude by highlighting the importance of prophylactic anticoagulation in all COVID-19 hospitalized patients and reiterate the need for institution-specific guidelines for anticoagulation COVID-19 patients since individual institutions have different patient populations.

[Systematic review of the prognostic utility of D-dimer, disseminated intravascular coagulation, and anticoagulant therapy in COVID-19 critically ill patients]

During the new pandemic caused by SARS-CoV-2, there is short knowledge regarding the management of different disease areas, such as coagulopathy and interpretation of D-dimer levels, its association with disseminated intravascular coagulation (DIC) and controversy about the benefit of anticoagulation. Thus, a systematic review has been performed to define the role of D-dimer in the disease, the prevalence of DIC and the usefulness of anticoagulant treatment in these patients. A literature search was performed to analyze the studies of COVID-19 patients. Four recommendations were drawn based on expert opinion and scientific knowledge, according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. The present review suggests the presence of higher levels of D-dimer in those with worse prognosis, there may be an overdiagnosis of DIC in the course of the disease and there is no evidence on the benefit of starting anticoagulant treatment based only on isolated laboratory data.

The Interactions of Nintedanib and Oral Anticoagulants-Molecular Mechanisms and Clinical Implications

Nintedanib is a synthetic orally active tyrosine kinase inhibitor, whose main action is to inhibit the receptors of the platelet-derived growth factor, fibroblast growth factor and vascular endothelial growth factor families. The drug also affects other kinases, including Src, Flt-3, LCK, LYN. Nintedanib is used in the treatment of idiopathic pulmonary fibrosis, chronic fibrosing interstitial lung diseases and lung cancer. The mechanism of action suggests that nintedanib should be considered one of the potential agents for inhibiting and revising the fibrosis process related to COVID-19 infections. Due to the known induction of coagulation pathways during COVID-19 infections, possible interaction between nintedanib and anticoagulant seems to be an extremely important issue. In theory, nintedanib could increase the bleeding risk, thrombosis and lead to thrombocytopenia. The data from clinical trials on the concomitant use of nintedanib and antithrombotic agents is very limited as this patient group was within the standard exclusion criteria. Nintedanib is an important therapeutic option, despite its interaction with anticoagulants. If anticoagulant therapy is necessary, the more effective and safer option is the concomitant administration of DOACs and nintedanib, especially when drug-monitored therapy will be used in patients at high risk of bleeding complications.

Thrombotic Complications of COVID-19 Infection: A Review

The novel coronavirus (severe acute respiratory syndrome CoV-2 [SARS-CoV-2]), also known as COVID-19, is a single-stranded enveloped RNA virus that created a Public Health Emergency of International Concern in January 2020, with a global case burden of over 15 million in just 7 months. Infected patients develop a wide range of clinical manifestations-typically presenting with fever, cough, myalgia, and fatigue. Severely ill patients may fall victim to acute respiratory distress syndrome, acute heart injuries, neurological manifestations, or complications due to secondary infections. These critically ill patients are also found to have disrupted coagulation function, predisposing them to consumptive coagulopathies, and both venous and thromboembolic complications. Common laboratory findings include thrombocytopenia, elevated D-dimer, fibrin degradation products, and fibrinogen, all of which have been associated with greater disease severity. Many cases of pulmonary embolism have been noted, along with deep vein thrombosis, ischemic stroke, myocardial infarction, and systemic arterial embolism. The pathogenesis of coronavirus has not been completely elucidated, but the virus is known to cause excessive inflammation, endothelial injury, hypoxia, and disseminated intravascular coagulation, all of which contribute to thrombosis formation. These patients are also faced with prolonged immobilization while staying in the hospital or intensive care unit. It is important to have a high degree of suspicion for thrombotic complications as patients may rapidly deteriorate in severe cases. Evidence suggests that prophylaxis with anticoagulation may lead to a lower risk of mortality, although it does not eliminate the possibility. The risks and benefits of anticoagulation treatment should be considered in each case. Patients should be regularly evaluated for bleeding risks and thrombotic complications.