American Society of Hematology living guidelines on the use of anticoagulation for thromboprophylaxis in patients with COVID-19: January 2022 update on the use of therapeutic-intensity anticoagulation in acutely ill patients

Comparison of the Efficacy and Safety of Low Molecular Weight Heparins and Fondaparinux in Patients With COVID-19: A Systematic Review and Meta-Analysis

Individuals diagnosed with COVID-19 are at a higher risk of arterial and venous thrombosis, mostly pulmonary microvascular thrombosis, which may significantly impair treatment and result in morbidity. This is a systematic review and meta-analysis of research papers that aim to evaluate the risk of bleeding and thrombosis among patients treated with low molecular weight heparin or fondaparinux (LMWH/F). Additionally, we measured the overall death events. This study was conducted in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. A search was conducted in the Clinicaltrials.gov, PubMed, Scopus, and Web of Science databases to identify observational cohort studies and randomized-controlled clinical trials (RCTs) that compared LMWH/F in proven COVID-19 patients. A total of 220 people from two studies were included. Patients who were treated with fondaparinux had a lower risk of developing venous thromboembolism (VTE) (odds ratio (OR) 0.39; 95% confidence interval (CI) (0.14, 1.096); p = 0.168); pulmonary embolism (OR 0.169, 95% CI (0.021, 1.356), p = 0.094); and deep vein thrombosis compared to patients who received LMWH therapy. The data show a lower mortality rate in the LMWH groups (OR 1.135, 95% CI (0.463, 2.785), p = 0.781) and a lower frequency of bleeding (OR 1.657, 95% CI (0.456, 5.908), p = 0.436). Both drugs have shown anti-thrombotic properties in COVID-19 patients. Fondaparinux was somewhat more effective in reducing thrombosis episodes. This research demonstrates the safe use of LMWH for VTE prophylaxis in hospitalized COVID-19 patients based on bleeding and mortality outcomes.

Lessons Learned From Moving to Living Guidelines-The Canadian Clinical Practice Guideline for the Rehabilitation of Adults With Moderate-to-Severe TBI

OBJECTIVE

It is often challenging for providers to remain up to date with best practices gleaned from clinical research. Consequently, patients may receive inappropriate, suboptimal, and costly care. Living clinical practice guidelines (CPGs) maintain the methodological rigor of traditional CPGs but are continuously updated in response to new research findings, changes in clinical practice, and emerging evidence. The objective of this initiative was to discuss the lessons learned from the transformation of the Canadian Clinical Practice Guideline for the Rehabilitation of Adults with Traumatic Brain Injury (CAN-TBI) from a traditional guideline update model to a living guideline model.

DESIGN

The CAN-TBI Guideline provides evidence-based rehabilitative care recommendations for individuals who have sustained a TBI. The Guideline is divided into 2 sections: Section I, which provides guidance on the components of the optimal TBI rehabilitation system, and Section II, which focuses on the assessment and rehabilitation of brain injury sequelae. A comprehensive outline of the living guideline process is presented.

RESULTS

The CAN-TBI living guideline process has yielded 351 recommendations organized within 21 domains. Currently, 30 recommendations are supported by level A evidence, 81 recommendations are supported by level B evidence, and 240 consensus-based recommendations (level C evidence) comprise 68% of the CAN-TBI Guideline.

CONCLUSION

Given the increasing volume of research published on moderate-to-severe TBI rehabilitation, the CAN-TBI living guideline process allows for real-time integration of emerging evidence in response to the fastest-growing topics, ensuring that practitioners have access to the most current and relevant recommendations.

Converting IMPROVE bleeding and VTE risk assessment models into a fast-and-frugal decision tree for optimal hospital VTE prophylaxis

ABSTRACT

Current hospital venous thromboembolism (VTE) prophylaxis for medical patients is characterized by both underuse and overuse. The American Society of Hematology (ASH) has endorsed the use of risk assessment models (RAMs) as an approach to individualize VTE prophylaxis by balancing overuse (excessive risk of bleeding) and underuse (risk of avoidable VTE). ASH has endorsed IMPROVE (International Medical Prevention Registry on Venous Thromboembolism) risk assessment models, the only RAMs to assess short-term bleeding and VTE risk in acutely ill medical inpatients. ASH, however, notes that no RAMs have been thoroughly analyzed for their effect on patient outcomes. We aimed to validate the IMPROVE models and adapt them into a simple, fast-and-frugal (FFT) decision tree to evaluate the impact of VTE prevention on health outcomes and costs. We used 3 methods: the "best evidence" from ASH guidelines, a "learning health system paradigm" combining guideline and real-world data from the Medical University of South Carolina (MUSC), and a "real-world data" approach based solely on MUSC data retrospectively extracted from electronic records. We found that the most effective VTE prevention strategy used the FFT decision tree based on an IMPROVE VTE score of ≥2 or ≥4 and a bleeding score of <7. This method could prevent 45% of unnecessary treatments, saving ∼$5 million annually for patients such as the MUSC cohort. We recommend integrating IMPROVE models into hospital electronic medical records as a point-of-care tool, thereby enhancing VTE prevention in hospitalized medical patients.

COVID-19 therapeutics

SUMMARYSince the emergence of COVID-19 in 2020, an unprecedented range of therapeutic options has been studied and deployed. Healthcare providers have multiple treatment approaches to choose from, but efficacy of those approaches often remains controversial or compromised by viral evolution. Uncertainties still persist regarding the best therapies for high-risk patients, and the drug pipeline is suffering fatigue and shortage of funding. In this article, we review the antiviral activity, mechanism of action, pharmacokinetics, and safety of COVID-19 antiviral therapies. Additionally, we summarize the evidence from randomized controlled trials on efficacy and safety of the various COVID-19 antivirals and discuss unmet needs which should be addressed.

Appropriate thromboprophylaxis strategy for COVID-19 patients on dosage, antiplatelet therapy, outpatient, and postdischarge prophylaxis: a meta-analysis of randomized controlled trials

BACKGROUND

There was controversy surrounding the optimal thromboprophylaxis strategy for coronavirus disease 2019 (COVID-19) patients. This included debates on the dosage of anticoagulants for thromboembolism prophylaxis, the requirement for additional antiplatelet therapy, and the necessity of prophylaxis for outpatients and postdischarge. To explore this, the authors performed a meta-analysis of randomized controlled trials.

METHODS

PubMed, Cochrane Library, Embase, and Web of Science were last searched on 26 July 2023 for studies comparing the effect of different dose of anticoagulation, additional antiplatelet, and postdischarge prophylaxis for COVID-19 patients. The results of eligible studies were analyzed in terms of thromboembolism events, major bleeding and all-cause mortality during follow-up.

RESULTS

Our study included a total of 25 randomized controlled trials, involving 17 911 patients. Our results revealed that, compared to prophylactic dose, therapeutic dose showed lower thrombotic risk (RR, 0.66; 95% CI: 0.45-0.96) but had similar major bleeding risk for critically ill patients with COVID-19. On the other hand, intermediate dose and prophylactic dose demonstrated similar thromboembolism risk and major bleeding risk. For noncritically ill patients with COVID-19, therapeutic dose of anticoagulants was associated with lower thrombotic risk (RR, 0.50; 95% CI: 0.34-0.72) but, at the same time, increased the risk of major bleeding (RR, 2.01; 95% CI: 1.22-3.33). However, intermediate dose showed lower thromboembolism risk (RR, 0.38; 95% CI: 0.21-0.69) while maintaining a similar major bleeding risk. In critically ill patients, additional antiplatelet therapy showed similar thromboembolism, major bleeding risk, and mortality when compared to no treatment. For outpatients, additional prophylactic anticoagulation showed similar thromboembolism, major bleeding risk, and mortality when compared to no treatment. For postdischarge patients, postdischarge prophylaxis reduced thromboembolism risk (RR, 0.49; 95% CI: 0.31-0.76) but increased major bleeding risk (RR, 2.63; 95% CI: 1.13-6.14).

CONCLUSION

For noncritically ill patients, therapeutic dose prophylactic anticoagulation significantly reduced venous thromboembolism but increases major bleeding risk. Intermediate dose effectively lowered venous thromboembolism without raising major bleeding risk. The optimal dose and need for additional antiplatelet therapy in critically ill patients, as well as the necessity of prophylactic anticoagulation in outpatient and postdischarge patients, required further investigation and confirmation through rigorous evidence studies.

Chronic Anticoagulation in Patients with Atrial Fibrillation and COVID-19: A Systematic Review and Meta-Analysis

BACKGROUND

Coronavirus disease 2019 (COVID-19) is associated with hypercoagulability. It remains uncertain whether ongoing anticoagulation for atrial fibrillation (AF) in patients who later contract COVID-19 improves clinical outcomes.

OBJECTIVES

To compare chronic oral anticoagulation with no previous anticoagulation in patients with AF who contracted a COVID-19 infection concerning the outcomes of all-cause mortality, COVID-19 mortality, intensive care unit (ICU) admission, and hospitalization.

METHODS

We systematically searched PubMed, Embase, and Cochrane Library for eligible studies from inception to December 2022. We included studies comparing COVID-19 outcomes in patients with versus without prior chronic anticoagulation for AF. Risk ratios (RR) with 95% confidence intervals (CI) were pooled with a random-effects model. The level of significance was set at p < 0.05. Quality assessment and risk of bias were performed according to Cochrane recommendations.

RESULTS

Ten studies comprising 1,177,858 patients with COVID-19 and AF were identified, of whom 893,772 (75.9%) were on prior chronic anticoagulation for AF. In patients with COVID-19, being on chronic anticoagulation for AF significantly reduced all-cause mortality (RR 0.75; 95% CI 0.57 to 0.99; p = 0.048; I2 = 89%) and COVID-19-related mortality (RR 0.76; 95% CI 0.72 to 0.79; p < 0.001; I2 = 0%) when compared with no prior anticoagulation. In contrast, there was no difference between groups regarding hospitalization (RR 1.08; 95% CI 0.82 to 1.41; p = 0.587; I2 = 95%) or ICU admission (RR 0.86; 95% CI 0.68 to 1.09; p = 0.216; I2 = 69%).

CONCLUSIONS

In this meta-analysis, chronic anticoagulation for patients with AF who contracted COVID-19 was associated with significantly lower rates of all-cause mortality and COVID-19-related mortality as compared with no previous anticoagulation.

Effectiveness and safety of rivaroxaban for anticoagulation therapy in COVID-19: A meta-analysis of randomized controlled trials

OBJECTIVES

To evaluate the effectiveness and safety of rivaroxaban anticoagulation in COVID-19 patients.

METHODS

PubMed, Embase, Cochrane Library electronic databases, and ClinicalTrials.gov were searched to identify all relevant randomized controlled trial studies from December 2019 to July 2023.

RESULTS

A total of 6 randomized controlled trials, which included a total of 3323 patients, were considered for evaluation. Overall, short-term all-cause mortality and hospitalization rates were not significantly different between the rivaroxaban and control groups. Thrombotic events were significantly reduced in the rivaroxaban prophylaxis group compared to the placebo control group. However, the reduction in thrombotic events was not significantly different between rivaroxaban therapy and heparin or low-molecular-weight heparin (LMWH). Rivaroxaban prophylaxis and the therapeutic dose may be associated with a higher rate of overall bleeding rate, but major bleeding rates did not differ substantially.

CONCLUSION

Rivaroxaban may reduce thrombotic events in COVID-19 patients, but it does not appear to have an advantage over heparin or LMWH, and it may increase the risk of bleeding.INPLASY Reg. No.: INPLASY 202370097.

Which are the optimal thromboprophylaxis strategies for hospitalized patients with COVID-19? current controversies

Novel coronavirus 2019 (COVID-19) represents a significant risk factor for the development of venous thromboembolism (VTE) in hospitalized with both moderate and severe/critical COVID-19. Herein, we present a brief updated review on emerging robust data on diverse thromboprophylaxis strategies used to mitigate VTE complications, as well as a personal point of view of current controversies in regards the use of therapeutic and prophylactic anticoagulation strategies, particularly in the moderately-ill subgroup of patients with COVID-19.

Association between antithrombotic therapy and mortality in patients hospitalized for COVID‑19

BACKGROUND

The prothrombotic state is a common abnormality in patients with coronavirus disease 2019 (COVID-19). However, there is controversy over the use of anticoagulants, especially oral anticoagulants (OAC) due to limited studies. We sought to evaluate the association between antithrombotic therapy on mortality and clinical outcomes in patients hospitalized for COVID-19 through propensity score matching (PSM) analysis.

METHODS

A retrospective cohort study was performed to include adult patients with COVID-19 in a university hospital. The primary outcome was in-hospital mortality. Secondary outcomes included intensive care unit (ICU) admission, mechanical ventilation, and acute kidney injury (AKI) during hospitalization. PSM was used as a powerful tool for matching patients' baseline characteristics. Adjusted odds ratios (aOR) with 95% confidence intervals (CI) were calculated from the models.

RESULTS

Of 4,881 COVID-19 patients during the study period, 690 (14.1%) patients received antithrombotic therapy and 4,191 (85.9%) patients were under no antithrombotic therapy. After adjustment with multivariate regression analysis, patients receiving OAC, compared with those who did not receive any antithrombotic therapy, had significantly lower odds for in-hospital mortality (aOR: 0.46. 95% CI: 0.24 to 0.87; P= 0.017). PSM analysis observed similar results (aOR: 0.35. 95% CI: 0.19 to 0.61; P< 0.001). Moreover, in critically ill patients who received mechanical ventilation, antithrombotic treatment (aOR: 0.54. 95% CI: 0.32 to 0.89; P= 0.022) was associated with reduced risk of mortality.

CONCLUSIONS

The application OACs was associated with reduced hospital mortality and mechanical ventilation requirement in COVID-19 patients. Besides, antithrombotic treatment was associated with a reduction in in-hospital mortality among critically ill COVID-19 patients who required mechanical ventilation.

Thrombo-inflammatory response in hospitalised patients with COVID-19: a single institution experience

BACKGROUND

Severe COVID-19 causes acute inflammation, which is complicated by venous thromboembolism events (VTE). However, it is unclear if VTE risk has evolved over time since the COVID-19 outbreak.

AIMS

To determine markers of thrombo-inflammation and rates of symptomatic VTE in patients hospitalised for COVID-19 in a metropolitan hospital in Sydney, Australia.

METHODS

A retrospective, single-centre, cohort study was performed by reviewing electronic medical records of consecutive patients admitted to Royal Prince Alfred Hospital between March 2020 and September 2021. This period included three waves of COVID-19 outbreaks in Australia with the ancestral, alpha and delta variants. Standard coagulation assays and inflammatory markers were recorded over 4 weeks.

RESULTS

A total of 205 patients were consecutively admitted during the study period. Activated partial thromboplastin time, neutrophil count and C-reactive protein (CRP) were significantly increased in patients hospitalised in the intensive care unit (ICU) compared with non-ICU patients. The use of anti-inflammatory medication increased in 2021 compared with 2020. The mortality rate was 7.3% in our cohort. Ninety-four per cent of patients received anticoagulation with 6.3% of patients developing VTE.

CONCLUSION

We observed lower rates of VTE compared to the internationally reported rate for the same period. We conclude that in the setting of controlled hospital admission rate and standard anticoagulation guidelines, COVID-19 resulted in similar thrombo-inflammatory response and VTE rates over the first 1.5 years of the pandemic.

Low-molecular-weight heparin for the prevention of clinical worsening in severe non-critically ill COVID-19 patients: a joint analysis of two randomized controlled trials

Coronavirus disease 2019 (COVID-19) carries a high risk of vascular thrombosis. However, whether a specific anticoagulation intensity strategy may prevent clinical worsening in severe COVID-19 patients is still debated. We conducted a joint analysis of two randomized controlled trials, COVID-19 HD (NCT044082359) and EMOS-COVID (NCT04646655), to assess the efficacy and safety of two anticoagulant regimens in hospitalized severe COVID-19 patients. Subjects with COVID-19-associated respiratory compromise and/or coagulopathy were randomly assigned to low (4000 IU qd) or high (70 IU Kg-1 every 12 h) enoxaparin dose. The primary efficacy endpoint was clinical worsening within 30 days, defined as the occurrence of at least one of the following events, whichever came first: in-hospital death, evidence of arterial or venous thromboembolism, acute myocardial infarction, need for either continuous positive airway pressure (CPAP) or non-invasive ventilation (NIV) in patients receiving standard oxygen therapy or none at randomization, and need for mechanical ventilation in any patient. The safety endpoint was major bleeding. We estimated the relative risk (RR) and its 95% confidence interval (CI) for the outcomes. Among 283 patients included in the study (144 in the low-dose and 139 in the high-dose group), 118 (41.7%) were on NIV or CPAP at randomization. 23/139 (16.5%) patients in the high-dose group reached the primary endpoint compared to 33/144 (22.9%) in the low-dose group (RR 0.72, 95% CI 0.45-1.17). No major bleeding was observed. No significant differences were found in the clinical worsening of hospitalized COVID-19 patients treated with high versus low doses of enoxaparin.

Hemograms and serial hemogram-derived ratios in survivors and non-survivors of COVID-19 in Campinas, Brazil

INTRODUCTION

The hemogram and hemogram-derivative ratios (HDRs) are becoming markers of the severity and mortality of COVID-19. We evaluated the hemograms and serial weekly HDRs [neutrophil-lymphocyte ratio (NLR), monocyte-lymphocyte ratio (MLR), platelet-lymphocyte ratio (PLR), neutrophil-platelet ratio (NPR) and systemic immune-inflammatory index (SII)] in the survivors and non-survivors of COVID-19.

METHODS

We retrospectively reviewed the medical notes and serial hemograms of real-time reverse-transcription polymerase chain reaction (RT-PCR)-confirmed COVID-19 adults hospitalized from April 2020 to March 2021 from the time of diagnosis to the 3rd week of diagnosis.

RESULTS

Of the 320 adults, 257 (80.3%) were survivors and had a lower mean age than the non-survivors (57.73 vs. 64.65 years, p < 0.001). At diagnosis, the non-survivors had lower hematocrit (p = 0.021), and lymphocyte (p = 0.002) and basophil (p = 0.049) counts and the hematocrit showed a p-value (Is this what you meant???) of 0.021); higher NLR (p < 0.001), PLR (p = 0.047), NPR (p = 0.022) and SII (p = 0.022). Using general linear models, the survivors and non-survivors showed significant variations with weekly lymphocyte count (p < 0.001), neutrophil count (p = 0.005), NLR (p = 0.009), MLR (p = 0.010) and PLR (p = 0.035). All HDRs remained higher in the non-survivors in the 2nd week and 3rd week of diagnosis and the HDRs were higher in the intubated patients than in the non-intubated patients. The NLR and SII were more efficient predictors of mortality in COVID-19 patients.

CONCLUSIONS

This study shows that serial lymphocyte and neutrophil counts, NLR, PLR, MLR, NPR and SII could serve as good and easily accessible markers of severity and predictors of outcomes in COVID-19 patients and should be used for the monitoring of treatment response.

Estrogen-based hormonal therapy and the risk of thrombosis in COVID-19 patients

OBJECTIVE

Estrogen-containing contraceptives and hormone replacement therapy are used commonly, however, the risks of venous and arterial thrombosis imparted by such medications during COVID-19 infection or other similar viral infections remain undescribed.

METHODS

To assess the risk of venous and arterial thrombosis in patients receiving oral estrogen-containing therapy (ECT) with COVID-19 as compared to those receiving non-estrogen-based hormonal therapy, we conducted a multicenter cohort study of 991 patients with confirmed COVID-19 infection, 466 receiving estrogen-containing hormonal therapy, and 525 receiving progestin-only or topical therapy.

RESULTS

The use of estrogen-containing therapy was found to significantly increase the risk of venous thromboembolism (VTE) following COVID-19 diagnosis after controlling for age (HR 5.46 [95% CI 1.12-26.7, p = .036]). This risk was highest in patients over age 50, with 8.6% of patients receiving estrogen-containing therapy diagnosed with VTE compared to 0.9% of those receiving non-estrogen-based therapies (p = .026). The risk of arterial thrombosis was not significantly associated with oral estrogen use.

CONCLUSIONS

These results suggest that estrogen-containing therapy is associated with a significantly increased risk of VTE in COVID-19 patients, especially in older individuals. These findings may guide provider counseling and management of patients with COVID-19 on estrogen-containing therapy.

A Delphi consensus on the management of anticoagulation in the COVID-19 pandemic: the MONACO study

Background

During the COVID-19 pandemic, guideline documents on the management of anticoagulation were rapidly published. However, these documents did not follow a structured methodology, and significant differences existed between the guidelines. The aim of this expert consensus was to provide recommendations on the clinical management of oral anticoagulation in patients in the context of the COVID-19 pandemic.

Methods

A two-round Delphi study was conducted using an online survey. In the first round, panellists expressed their level of agreement with the items on a 9-point Likert scale. Items were selected if they received approval from ≥66.6% of panellists and if they were agreed by the scientific committee. In the second round, panellists revaluated those items that did not meet consensus in the first round.

Results

A total of 147 panellists completed the first round, and 144 of them completed the second round. Consensus was reached on 161 items included in five dimensions. These dimensions addressed: (I) management of anticoagulation in patients with atrial fibrillation (AF) without mechanical valves or moderate/severe mitral stenosis during COVID-19 infection; (II) thromboprophylaxis in patients hospitalised for COVID-19; (III) management of anticoagulation at hospital discharge/after COVID-19; (IV) anticoagulation monitoring in the COVID-19 pandemic setting; and (V) role of telemedicine in the management and follow-up of patients with AF in the COVID-19 pandemic setting.

Conclusions

These areas of collective agreement could specially guide clinicians in making decisions regarding anticoagulation in patients with COVID-19 during hospitalisation and at discharge, where results from clinical trials are still limited and, in some cases, conflicting.

Anticoagulant therapy in COVID-19: A narrative review

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can manifest itself in several ways, including coagulopathy and thrombosis. These complications can be the first and sometimes only manifestations of SARS-CoV-2 infection and can occur early or late in the course of the disease. However, these symptoms are more prevalent in hospitalized patients with venous thromboembolism, particularly those admitted to intensive care units. Moreover, various forms of arterial and venous thrombosis, or micro- or macro-vasculature embolisms, have been reported during the current pandemic. They have led to harmful consequences, such as neurological and cardiac events, nearly all resulting from the hypercoagulable state caused by this viral infection. The severe hypercoagulability observed in patients with COVID-19 accounts for most cases of the disease that become critical. Therefore, anticoagulants seem to be one of the most vital therapeutics for treating this potentially life-threatening condition. In the current paper, we present a thorough review of the pathophysiology of COVID-19-induced hypercoagulable state and the use of anticoagulants to treat SARS-CoV-2 infections in different patient groups, as well as their pros and cons.

Effects of Different Anticoagulation Doses on Moderate-to-Severe COVID-19 Pneumonia With Hypoxemia

Background COVID-19 is a prothrombotic disease that can cause thromboembolism and microthrombi, which could lead to multiorgan failure and death. Since COVID-19 is a relatively new disease, there are guidelines for anticoagulation dosing for COVID-19 patients without consensus on the dosing. We studied the effects of different doses of anticoagulation in hospitalized patients with COVID-19 pneumonia and hypoxemia on any differences in need for high-flow oxygen, mechanical ventilation, and mortality. We also analyzed the patient population who benefited most from anticoagulation. Methodology We performed a retrospective chart review of all patients who were admitted with the diagnosis of COVID-19 infection with positive polymerase chain reaction, pneumonia (confirmed either by chest X-ray or CT chest), and hypoxemia (oxygen saturation of <94%, while on room air). These patients were studied for outcomes (the need for high-flow oxygen, the requirement for mechanical ventilation, and overall mortality) for different doses of anticoagulation (prophylactic, escalated, and therapeutic). Results The sample consists of 132 subjects, predominantly males (116, 87%), with a mean age of 59 years and a standard deviation of 15. About one-third of the participants had diabetes, and more than 50% had hypertension. Additionally, 27 (20.3%) had a history of heart disease, and 70 (53%) of the subjects were admitted to the intensive care unit (ICU) at some point during the study. Among those admitted to the ICU, about 11 (8%) subjects required mechanical ventilation and 16 (12%) passed away during the study. Those who died had higher use of high-flow oxygen, noninvasive mechanical ventilation, and invasive mechanical ventilation and had a longer stay on mechanical ventilation. There was no significant difference in mortality or need for mechanical ventilation for any strategy of anticoagulation. Conclusions Different doses of anticoagulation did not show any statistically significant relationship between the need for mechanical ventilation and mortality. More patients on high-flow oxygen had received escalated doses of anticoagulation as compared to those who were not on high-flow oxygen. Anticoagulation levels did not have any statistically significant effect on overall survival of patients.

Cochrane Corner: The use of anticoagulants in patients hospitalised with COVID-19

Background

In this Cochrane Corner, we highlight the main findings of a Cochrane Review by Flumignan et al. entitled 'Anticoagulants for people hospitalised with COVID-19' and discuss the implications of these findings for research and practice in South Africa. In particular, we underscore the need for additional, high-quality, randomised controlled trials comparing different intensities of anticoagulation in patients with COVID-19 illness. Individuals in the intensive care unit and those hospitalised with another illness who are incidentally found to be infected with SARS-CoV-2 should still only be treated with prophylactic-dose low-molecular-weight heparin.

Contributions of the study

This Cochrane Corner summarises findings in a recent systematic review on the use of anticoagulation in people hospitalised with COVID-19, and provides insights on the implications of these findings for implementation by clinicians in South Africa. It highlights the need for clinicians to balance the benefits and harms of providing an anticoagulant, while considering the patients underlying risk for bleeding and thromboembolism.

Quantitative chest CT imaging characteristics and outcome of patients with COVID-19 associated pulmonary artery thrombosis: A single-center retrospective cohort study

Coronavirus disease 2019 (COVID-19)-associated pulmonary thrombotic events occur frequently and are associated with disease severity and worse clinical outcomes. We aimed to describe the clinical and quantitative chest computed tomography (CT) imaging characteristics based on density ranges (Hounsfield units) and the outcomes of patients with COVID-19 associated pulmonary artery thrombosis. This retrospective cohort study included all patients with COVID-19 hospitalized in a tertiary care hospital between March 2020 and June 2022 who underwent a CT pulmonary angiography. We included 73 patients: 36 (49.3%) with and 37 (50.7%) without pulmonary artery thrombosis. The in-hospital all-cause mortality was 22.2 versus 18.9% ( P  = .7), and the intensive care unit admission rates were 30.5 versus 8.1% ( P  = .01) at the time of diagnosis of pulmonary artery thrombosis. Except for D-dimers (median of 3142 vs 533, P  = .002), the other clinical, coagulopathy, and inflammatory markers were similar. Logistic regression analysis revealed that only D-dimers were associated with pulmonary artery thrombosis ( P  = .012). ROC curve analysis of D-dimers showed that a value greater than 1716 ng/mL predicted pulmonary artery thrombosis with an area under the curve of 0.779, 72.2% sensitivity, and 73% specificity (95% CI 0.672-0.885). Peripheral distribution of pulmonary artery thrombosis was recorded in 94.5% of cases. In the lower lobes of the lungs, the incidence of pulmonary artery thrombosis was 6 times higher than that in the upper lobes (58-64%), with a percentage of lung injury of 80% to 90%. Analysis of the distribution of arterial branches with filling defects revealed that 91.6% occurred in lung areas with inflammatory lesions. Quantitative chest CT imaging provides valuable information regarding the extent of COVID-19 associated lung damage and can be used to anticipate the co-location of pulmonary immunothrombotic events. In patients with severe COVID-19, in-hospital all-cause mortality was similar regardless of the presence of associated distal pulmonary thrombosis.

COVID-19-associated Coagulopathy Characterization using Rotational Thromboelastometry in a Prospective, Observational Cohort Study: The HemoCoV Study

INTRODUCTION

COVID-19-associated coagulopathy includes systemic and endothelial inflammation with coagulation dysregulation related to immunothrombosis. The aim of this study was to characterize this complication of SARS-CoV-2 infection in patients with moderate to severe COVID-19.

METHODS

An open-label, prospective observational study conducted in patients with COVID-19 moderate to severe acute respiratory failure admitted to an intensive care unit (ICU). Coagulation testing, including thromboelastometry, biochemical analysis and clinical variables, were collected at prespecified time points during the 30 days of ICU stay.

RESULTS

The study included 145 patients, 73.8% male, with a median age of 68 years (interquartile range - IQR 55 - 74). The most prevalent comorbidities were arterial hypertension (63.4%), obesity (44.1%) and diabetes (22.1%). Simplified acute physiology score II (SAPS II) was on average 43.5 (11 - 105) and sequential organ failure assessment (SOFA) at admission was 7.5 (0 - 14). During ICU stay, 66.9% of patients underwent invasive mechanical ventilation and 18.4% extracorporeal membrane oxygenation support; thrombotic and hemorrhagic events occurred in 22.1% and 15.1% of the patients respectively; anticoagulation with heparin was present in 99.2% of patients since early ICU stay. Death occurred in 35% of patients. Longitudinal studies revealed changes in almost all coagulation tests during the ICU stay. SOFA score, lymphocyte counts, some biochemical, inflammatory and coagulation parameters, including hypercoagulability and hypofibrinolysis seen in thromboelastometry, differed significantly (p < 0.05), between ICU admission and discharge. Hypercoagulability and hypofibrinolysis persisted throughout ICU hospitalization, showing higher incidence and severity in non-survivors.

CONCLUSION

COVID-19-associated coagulopathy is characterized by hypercoagulability and hypofibrinolysis from ICU admission, and persisted throughout the clinical course in severe COVID-19. These changes were more pronounced in patients with higher disease burden and in non-survivors.

Role of Therapeutic Anticoagulation in COVID-19: The Current Situation

Thrombotic complications from COVID-19 are now well known and contribute to significant morbidity and mortality. Different variants confer varying risks of thrombotic complications. Heparin has anti-inflammatory and antiviral effects. Due to its non-anticoagulant effects, escalated-dose anticoagulation, especially therapeutic-dose heparin, has been studied for thromboprophylaxis in hospitalized patients with COVID-19. Few randomized, controlled trials have examined the role of therapeutic anticoagulation in moderately to severely ill patients with COVID-19. Most of these patients had elevated D-dimers and low bleeding risks. Some trials used an innovative adaptive multiplatform with Bayesian analysis to answer this critical question promptly. All the trials were open-label and had several limitations. Most trials showed improvements in the meaningful clinical outcomes of organ-support-free days and reductions in thrombotic events, mainly in non-critically-ill COVID-19 patients. However, the mortality benefit needed to be more consistent. A recent meta-analysis confirmed the results. Multiple centers initially adopted intermediate-dose thromboprophylaxis, but the studies failed to show meaningful benefits. Given the new evidence, significant societies have suggested therapeutic anticoagulation in carefully selected patients who are moderately ill and do not require an intensive-care-unit level of care. There are multiple ongoing trials globally to further our understanding of therapeutic-dose thromboprophylaxis in hospitalized patients with COVID-19. In this review, we aim to summarize the current evidence regarding the use of anticoagulation in patients with COVID-19 infection.

Coagulopathy and thromboembolic events a pathogenic mechanism of COVID-19 associated with mortality: An updated review

During 2019, the SARS-CoV-2 emerged from China, and during months, COVID-19 spread in many countries around the world. The expanding data about pathogenesis of this virus could elucidate the exact mechanism by which COVID-19 caused death in humans. One of the pathogenic mechanisms of this disease is coagulation. Coagulation disorders that affect both venous and arterial systems occur in patients with COVID-19. The possible mechanism involved in the coagulation could be excessive inflammation induced by SARS-CoV-2. However, it is not yet clear well how SARS-CoV-2 promotes coagulopathy. However, some factors, such as pulmonary endothelial cell damage and some anticoagulant system disorders, are assumed to have an important role. In this study, we assessed conducted studies about COVID-19-induced coagulopathy to obtain clearer vision of the wide range of manifestations and possible pathogenesis mechanisms.

COVID-19 and Sickle Cell Disease: Two Independent Risk Factors for Venous Thromboembolism

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been widely documented as a multi-systemic illness and associated with an increased incidence of thromboses. Likewise, sickle cell disease (SCD) is a hematologic disease responsible for widespread effects on the vasculature and is also associated with elevated thrombotic risk. In this review, we examine the incidence rates of venous thromboembolism (VTE) in SCD and COVID-19 independently and review the mechanisms of coagulopathy associated with both diseases. We describe the possible associations and commonalities between VTE mechanisms, as both diseases cause widespread inflammation that influences each tenet of Virchow's triad. We also discuss current anticoagulation guideline recommendations for the prevention of VTE events in each of these diseases. We report on current literature to date describing rates of VTE in SCD-COVID-19 patients and outline prospective areas of research to further understand the possible synergistic influence of coagulopathy in these patients. The association between SCD and COVID-19 remains a largely under-researched area of coagulopathy in current hematology and thrombotic literature, and our report lays out potential future prospects in the field.

Effectiveness and Safety of Enoxaparin Versus Unfractionated Heparin as Thromboprophylaxis in Hospitalized COVID-19 Patients: Real-World Evidence

BACKGROUND

Coronavirus 2019 (COVID-19) patients are at risk of thrombosis. Literature that compares the effectiveness of enoxaparin to unfractionated heparin (UFH) in COVID-19 patients is scarce.

OBJECTIVE

We aimed to evaluate the effectiveness and safety of enoxaparin compared with UFH when used at their standard/intermediate dosing in COVID-19 patients.

METHODS

This was a retrospective study conducted at a large COVID-19 center located in Eastern Province, Saudi Arabia. Confirmed COVID-19 cases (≥18 years old) admitted between January and December 2020 were randomly screened for inclusion. Exclusion criteria were patients receiving therapeutic anticoagulation, on chronic anticoagulation, had active bleeding, a platelet count <25 × 109/L, or an incomplete electronic file. The primary endpoint was the occurrence of any thrombotic event (pulmonary embolism, deep venous thrombosis, stroke, or myocardial infarction) or mortality. Secondary endpoints were major or minor bleeding. We applied inverse propensity score weighting (IPTW) with survival analysis to analyze the primary endpoint. Logistic regression was used for the secondary endpoint.

RESULTS

A total of 980 patients were included (enoxaparin, n = 470 and UFH, n = 510) with a mean age (±SD) of 47.7 (± 12.3) for the enoxaparin arm and 52 (±13.9) for the UFH arm. There was a statistically significant difference in the primary endpoint with an adjusted hazard ratio (aHR) of 0.46 (95%CI: 0.22 to 0.96, P = 0.039) in favor of the enoxaparin arm. There was no statistically significant difference in major or minor bleeding rates between the two arms.

CONCLUSION AND RELEVANCE

When compared with UFH, enoxaparin was associated with a significant reduction in thrombotic events or mortality among COVID-19 patients. The results need confirmation from randomized controlled trials.

Improving guideline-concordant thromboprophylaxis prescribing for children admitted to hospital with COVID-19

BACKGROUND

The incidence of venous thrombo-embolism (VTE) in hospitalized children has increased by 130%-200% over the last two decades. Given this increase, many centers utilize electronic clinical decision support (CDS) to prognosticate VTE risk and recommend prophylaxis. SARS-CoV-2 infection (COVID-19) is a risk factor for VTE; however, CDS developed before the COVID-19 pandemic may not accurately prognosticate VTE risk in children with COVID-19. This study's objective was to identify areas to improve thromboprophylaxis recommendations for children with COVID-19.

METHODS

Inpatients with a positive COVID-19 test at admission were identified at a quaternary-care pediatric center between March 1, 2020 and January 20, 2022. The results of the institution's automated CDS thromboprophylaxis recommendations were compared to institutional COVID-19 thromboprophylaxis guidelines and to the actual thromboprophylaxis received. CDS optimization was performed to improve adherence to COVID-19 thromboprophylaxis recommendations.

RESULTS

Of the 329 patients included in this study, 106 (28.2%) were prescribed pharmaco-prophylaxis, 167 (50.8%) were identified by the institutional COVID-19 guidelines as requiring pharmaco-prophylaxis, and 45 (13.2%) were identified by the CDS as needing pharmaco-prophylaxis. On univariate analysis, only age 12 years or more was associated with recipient of appropriate prophylaxis (OR 1.78, 95% CI: 1.13-2.82, p = .013). Five patients developed VTEs; three had symptoms at presentation, two were identified as high risk for VTE by both the automated and best practice assessments but were not prescribed pharmaco-prophylaxis.

CONCLUSION

Automated thromboprophylaxis recommendations developed prior to the COVID-19 pandemic may not identify all COVID-19 patients needing pharmaco-prophylaxis. Existing CDS tools need to be updated to reflect COVID-19-specific risk factors for VTEs.

The Conundrum of Anticoagulation for Hospitalized Patients with Covid-19

Thrombosis in patients with coronavirus disease 2019 (Covid-19) is driven by complex interactions between immune, complement, fibrinolytic, endothelial, and coagulation systems.1 In addition to venous thromboembolism (VTE), microthrombi have also been implicated in contributing to end-organ damage, such as acute respiratory distress syndrome and kidney dysfunction, as well as to overall mortality.1 As available therapies, variants, and vaccines have evolved, so have reported rates of VTE attributable to Covid-19.

Anticoagulation Strategies in Non-Critically Ill Patients with Covid-19

BACKGROUND: Optimal thromboprophylaxis for hospitalized patients with coronavirus disease 2019 (Covid-19) is uncertain. METHODS: In an open-label, adaptive platform trial, we randomly assigned hospitalized adults with Covid-19 to low-dose low-molecular-weight heparin thromboprophylaxis or intermediate-dose or low-dose plus aspirin. In response to external evidence, the aspirin intervention was discontinued and a therapeutic-dose arm added. The primary end point was death or the requirement for new organ support by day 28, analyzed with a Bayesian logistic model. Enrolment was closed as a result of operational constraints. RESULTS: Between February 2021 and March 2022, 1574 patients were randomly assigned. Among 1526 participants included in the analysis (India, n=1273; Australia and New Zealand, n=138; and Nepal, n=115), the primary outcome occurred in 35 (5.9%) of 596 in low-dose, 25 (4.2%) of 601 in intermediate-dose, 20 (7.2%) of 279 in low-dose plus aspirin, and 7 (14%) of 50 in therapeutic-dose anticoagulation. Compared with low-dose thromboprophylaxis, the median adjusted odds ratio for the primary outcome for intermediate-dose was 0.74 (95% credible interval [CrI], 0.43 to 1.27; posterior probability of effectiveness [adjusted odds ratio<1; Pr], 86%), for low-dose plus aspirin 0.88 (95% CrI, 0.47 to 1.64; Pr, 65%), and for therapeutic-dose anticoagulation 2.22 (95% CrI, 0.77 to 6.20; Pr, 7%). Overall thrombotic and bleeding rates were 0.8% and 0.4%, respectively. There were 10 serious adverse reactions related to anticoagulation strategy, of which nine were grade 1 or 2 across study interventions and one grade 4 episode of retroperitoneal hematoma in a patient receiving intermediate-dose anticoagulation. CONCLUSIONS: In hospitalized non–critically ill adults with Covid-19, compared with low-dose, there was an 86% posterior probability that intermediate-dose, 65% posterior probability that low-dose plus aspirin, and a 7% posterior probability that therapeutic-dose anticoagulation reduced the odds of death or requirement for organ support. No treatment strategy met prespecified stopping criteria before trial closure, precluding definitive conclusions. (Funded by Australian National Health and Medical Research Council or Medical Research Future Fund Investigator and Practitioner Grants and others; ClinicalTrials.gov number, NCT04483960.)

Omicron, Long-COVID, and the Safety of Elective Surgery for Adults and Children: Joint Guidance from the Therapeutics and Guidelines Committee of the Surgical Infection Society and the Surgery Strategic Clinical Network, Alberta Health Services

Background: Active and recent coronavirus disease 2019 (COVID-19) infections are associated with morbidity and mortality after surgery in adults. Current recommendations suggest delaying elective surgery in survivors for four to 12 weeks, depending on initial illness severity. Recently, the predominant causes of COVID-19 are the highly transmissible/less virulent Omicron variant/subvariants. Moreover, increased survivability of primary infections has engendered the long-COVID syndrome, with protean manifestations that may persist for months. Considering the more than 600,000,000 COVID-19 survivors, surgeons will likely be consulted by recovered patients seeking elective operations. Knowledge gaps of the aftermath of Omicron infections raise questions whether extant guidance for timing of surgery still applies to adults or should apply to the pediatric population. Methods: Scoping review of relevant English-language literature. Results: Most supporting data derive from early in the pandemic when the Alpha variant of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) predominated. The Omicron variant/subvariants generally cause milder infections with less organ dysfunction; many infections are asymptomatic, especially in children. Data are scant with respect to adult surgical outcomes after Omicron infection, and especially so for pediatric surgical outcomes at any stage of the pandemic. Conclusions: Numerous knowledge gaps persist with respect to the disease, the recovered pre-operative patient, the nature of the proposed procedure, and supporting data. For example, should the waiting period for all but urgent elective surgery be extended beyond 12 weeks, e.g., after serious/critical illness, or for patients with long-COVID and organ dysfunction? Conversely, can the waiting periods for asymptomatic patients or vaccinated patients be shortened? How shall children be risk-stratified, considering the distinctiveness of pediatric COVID-19 and the paucity of data? Forthcoming guidelines will hopefully answer these questions but may require ongoing modifications based on additional new data and the epidemiology of emerging strains.

Postoperative Outcomes in Patients Undergoing Orthopaedic Surgery Within 90 Days of Coronavirus Disease 2019

INTRODUCTION

Coronavirus disease 2019 (COVID-19) has resulted in a global pandemic with several hundred million infections worldwide. COVID-19 causes systemic complications that last beyond the initial infection. It is not known whether patients who undergo elective orthopaedic surgeries after COVID-19 are at increased risk of complications. The purpose of this study was to evaluate whether patients who undergo orthopaedic procedures after recent COVID-19 diagnosis are at increased risk of complications compared with those who have not had a recent COVID-19 diagnosis.

METHODS

The TriNetX Research Network database was queried for patients undergoing elective orthopaedic surgeries from April 2020 to January 2022 in the following subspecialties: arthroscopic surgery, total joint arthroplasty, lumbar fusion, upper extremity surgery, foot and ankle (FA) surgery. Cohorts were defined by patients undergoing surgery with a diagnosis of COVID-19 from 7 to 90 days before surgery and those with no COVID-19 diagnosis 0 to 90 days before surgery. These cohorts were propensity-score matched based on differences in demographics and comorbidities. The matched cohorts were evaluated using measures of association analysis for complications, emergency department (ER) visits, and readmissions occurring 90 days postoperatively.

RESULTS

Patients undergoing arthroscopic surgery were more likely to experience venous thromboembolism (VTE) ( P = 0.006), myocardial infarction ( P = 0.001), and ER visits ( P = 0.001). Patients undergoing total joint arthroplasty were more likely to experience VTE ( P < 0.001), myocardial infarction ( P < 0.001), pneumonia ( P < 0.001), and ER visits ( P = 0.037). Patients undergoing lumbar fusion were more likely to experience VTE ( P = 0.016), infection ( P < 0.001), pneumonia ( P < 0.001), and readmission ( P = 0.006). Patients undergoing upper extremity surgery were more likely to experience VTE ( P = 0.001) and pneumonia ( P = 0.015). Patients undergoing foot and ankle surgery were more likely to experience VTE ( P < 0.001) and pneumonia ( P < 0.001).

CONCLUSION

There is an increased risk of complications in patients undergoing orthopaedic surgery after COVID-19 infection; all cohorts were at increased risk of VTE and most at increased risk of pneumonia. Additional investigation is needed to stratify the risk for individual patients.

Evaluation of a fast-and-frugal clinical decision algorithm ('pathways') on clinical outcomes in hospitalised patients with COVID-19 treated with anticoagulants

RATIONALE, AIMS AND OBJECTIVES

Critics have charged that evidence-based medicine (EBM) overemphasises algorithmic rules over unstructured clinical experience and intuition, but the role of structured decision support systems in improving health outcomes remains uncertain. We aim to assess if delivery of anticoagulant prophylaxis in hospitalised patients with COVID-19 according to an algorithm based on evidence-based clinical practice guideline (CPG) improved clinical outcomes compared with administration of anticoagulant treatment given at individual practitioners' discretion.

METHODS

An observational design consisting of the analysis of all acutely ill, consecutive patients (n = 1783) with confirmed COVID-19 diagnosis admitted between 10 March 2020 to 11 January 2022 to an US academic center. American Society of Haematology CPG for anticoagulant prophylaxis in hospitalised patients with COVID-19 was converted into a clinical pathway and translated into fast-and-frugal decision (FFT) tree ('algorithm'). We compared delivery of anticoagulant prophylaxis in hospitalised patients with COVID-19 according to the FFT algorithm with administration of anticoagulant treatment given at individual practitioners' discretion.

RESULTS

In an adjusted analysis, using combination of Lasso (least absolute shrinkage and selection operator) and propensity score based weighting [augmented inverse-probability weighting] statistical techniques controlling for cluster data, the algorithm did not reduce death, venous thromboembolism, or major bleeding, but helped avoid longer hospital stay [number of patients needed to be treated (NNT) = 40 (95% CI: 23-143), indicating that for every 40 patients (23-143) managed on FFT algorithm, one avoided staying in hospital longer than 10 days] and averted admission to intensive-care unit (ICU) [NNT = 19 (95% CI: 13-40)]. All model's selected covariates were well balanced. The results remained robust to sensitivity analyses used to test the stability of the findings.

CONCLUSIONS

When delivered using a structured FFT algorithm, CPG shortened the hospital stay and help avoided admission to ICU, but it did not affect other relevant outcomes.

Antithrombin Therapy: Current State and Future Outlook

Antithrombin (AT) is a natural anticoagulant pivotal in inactivating serine protease enzymes in the coagulation cascade, making it a potent inhibitor of blood clot formation. AT also possesses anti-inflammatory properties by influencing anticoagulation and directly interacting with endothelial cells. Hereditary AT deficiency is one of the most severe inherited thrombophilias, with up to 85% lifetime risk of venous thromboembolism. Acquired AT deficiency arises during heparin therapy or states of hypercoagulability like sepsis and premature infancy. Optimization of AT levels in individuals with AT deficiency is an important treatment consideration, particularly during high-risk situations such as surgery, trauma, pregnancy, and postpartum. Here, we integrate the existing evidence surrounding the approved uses of AT therapy, as well as potential additional patient populations where AT therapy has been considered by the medical community, including any available consensus statements and guidelines. We also describe current knowledge regarding cost-effectiveness of AT concentrate in different contexts. Future work should seek to identify specific patient populations for whom targeted AT therapy is likely to provide the strongest clinical benefit.

Thrombosis questions from the inpatient wards

The multifaceted pathophysiologic processes that comprise thrombosis and thromboembolic diseases take on a particular urgency in the hospitalized setting. In this review, we explore 3 cases of thrombosis from the inpatient wards: purpura fulminans, cancer-associated thrombosis with thrombocytopenia, and coronavirus disease 2019 (COVID-19) and the use of dose-escalated anticoagulation therapy and antiplatelet agents. We discuss the evaluation and management of purpura fulminans and the roles of plasma transfusion, protein C and antithrombin replacement, and anticoagulation in treating this disease. We present a framework for evaluating the etiologies of thrombocytopenia in cancer and review 2 strategies for anticoagulation management in patients with cancer-associated thrombosis and thrombocytopenia, including recent prospective data supporting the use of dose-modified anticoagulation based on platelet count. Last, we dissect the major clinical trials of therapeutic- and intermediate-dose anticoagulation and antiplatelet therapy in hospitalized patients with COVID-19, reviewing key recommendations from consensus guidelines while highlighting ways in which institutional and patient-tailored practices regarding antithrombotic therapies in COVID-19 may differ. Together, the cases highlight the diverse and dramatic presentations of macro- and microvascular thrombosis as encountered on the inpatient wards.

Investigating the association between IL-6 antagonist therapy and blood coagulation in critically ill patients with COVID-19: a protocol for a prospective, observational, multicentre study

INTRODUCTION

Hypercoagulation is one the main features of COVID-19. It is induced by the hyperinflammatory response that shifts the balance of haemostasis towards pro-coagulation. Interleukin-6 (IL-6) antagonist therapy has been recommended in certain subgroups of critically ill patients with COVID-19 to modulate inflammatory response. The interaction between immune response and haemostasis is well recognised. Therefore, our objective is to evaluate whether the modulation of the inflammatory response by IL-6 antagonist inflicts any changes in whole blood coagulation as assessed by viscoelastic methods in critically ill patients with COVID-19.

METHODS AND ANALYSIS

In this prospective observational study, we are going to collect data on inflammatory parameters and blood coagulation using the ClotPro^® device. The primary outcome is the change of the fibrinolytic system measured by the Lysis Time and Lysis onset time before and after immunomodulation therapy. Data will be collected before the IL-6 antagonist administration at baseline (T₀) then after 24, 48 hours, then on day 5 and 7 (T_1-4, respectively). Secondary outcomes include changes in other parameters related to inflammation, blood coagulation and biomarkers of endothelial injury.

ETHICS AND DISSEMINATION

Ethical approval was given by the Medical Research Council of Hungary (1405-3/2022/EÜG). All participants provided written consent. The results of the study will be disseminated through peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT05218369; Clinicaltrials.gov.

Venous Thromboembolic Disease in COVID-19, Pathophysiology, Therapy and Prophylaxis

For over two years, the world has been facing the epidemiological and health challenge of the coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Growing problems are also complications after the development of COVID-19 in the form of post and long- COVID syndromes, posing a challenge for the medical community, both for clinicians and the scientific world. SARS-CoV-2 infection is associated with an increased risk of cardiovascular complications, especially thromboembolic complications, which are associated with both thrombosis of small and very small vessels due to immunothrombosis, and the development of venous thromboembolism. Low molecular wight heparin (LMHW) are the basic agents used in the prevention and treatment of thromboembolic complications in COVID-19. There is still a great deal of controversy regarding both the prevention and treatment of thromboembolic complications, including the prophylaxis dose or the optimal duration of anticoagulant treatment in patients with an episode of venous thromboembolism.

Increased Susceptibility for Thromboembolic Events versus High Bleeding Risk Associated with COVID-19

The infection with the SARS-CoV-2 virus is associated with numerous systemic involvements. Besides the severe respiratory injuries and cardiovascular complications, it became obvious early on that this disease carries an increased risk of thromboembolic events, but a higher propensity for bleedings as well. We researched the medical literature over significant PubMed published articles debating on the prevalence, category of patients, the moment of occurrence, and evolution of venous thromboembolism (VTE), but also of venous and arterial “in situ” thrombosis (AT), and hemorrhagic events as well. Most researchers agree on an increased prevalence of thromboembolic events, ranging between 25 and 31% for VTE, depending on the analyzed population. For AT and hemorrhagic complications lower rates were reported, namely, about 2–3%, respectively, between 4.8 and 8%, occurring mostly in older patients, suffering from moderate/severe forms of COVID-19, with associated comorbidities. It is important to mention that patients suffering from hemorrhages frequently received thromboprophylaxis with anticoagulant drugs. As a consequence of thromboembolic and hemorrhagic complications which are both important negative prognostic factors, the evolution of patients infected with the SARS-CoV-2 virus is aggravated, determining an augmented morbidity and mortality of this population.

Correction of Anticoagulant Therapy in Patients with Severe COVID-19 Virus Infection Using a Thrombodynamics Coagulation Assay

BACKGROUND

The average frequency of thrombosis in patients with COVID-19 is still high despite low molecular weight heparin (LMWH) prophylactic. Global hemostasis assays, particularly thrombodynamics (TD), known to be sensitive to both hypercoagulation and heparin effects, could potentially be useful for individual management of anticoagulant therapy.

METHODS

A total of 74 patients with lung involvement >50% were randomized into two groups: Group A (44 patients) received weight-based dosing of LMWH, and Group B (30 patients) received the first LMWH dose by a weight-based dosing protocol and then received an adjusted dose based on TD daily results. The endpoints of the study were thrombosis and bleeding as well as discharge or death of the patient.

RESULTS

The incidence of thrombosis was 3 times lower in Group B under TD control compared to Group A without TD control: 7% versus 23 respectively (p = .05). The relative risk of thrombosis if the average clot growth rate V in TD exceeded the threshold value of 25 μm/min was 14.3 (p = .0005, 95% confidence interval 3.2-63.7). There were no clinically significant bleeding episodes in Group B while there were 7% in unregulated Group A. Mortality in Group B under TD control was lower than that in Group A without control: 27% versus 36%, respectively (p = .13).

CONCLUSIONS

The dosing LMWH under thrombodynamics control in severe patients with COVID-19 allows for a significant reduction in thrombotic complications. Long-term hypercoagulation revealed by thrombodynamics (3 and more days) is a strong predictor of thrombosis (AUC = 0.83).