Duration of venous thromboembolism risk across a continuum in medically ill hospitalized patients

Venous Thromboembolism Prevention in Rehabilitation: A Review and Practice Suggestions

ABSTRACT

Venous thromboembolism is a frequent complication of acute hospital care, and this extends to inpatient rehabilitation. The timely use of appropriate thromboprophylaxis in patients who are at risk is a strong, evidence-based patient safety priority that has reduced clinically important venous thromboembolism, associated mortality and costs of care. While there has been extensive research on optimal approaches to venous thromboembolism prophylaxis in acute care, there is a paucity of high-quality evidence specific to patients in the rehabilitation setting, and there are no clinical practice guidelines that make recommendations for (or against) thromboprophylaxis across the broad spectrum of rehabilitation patients. Herein, we provide an evidence-informed review of the topic with practice suggestions. We conducted a series of literature searches to assess the risks of venous thromboembolism and its prevention related to inpatient rehabilitation as well as in major rehabilitation subgroups. Mobilization alone does not eliminate the risk of venous thromboembolism after another thrombotic insult. Low molecular weight heparins and direct oral anticoagulants are the principal current modalities of thromboprophylaxis. Based on the literature, we make suggestions for venous thromboembolism prevention and include an approach for consideration by rehabilitation units that can be aligned with local practice.

The Role of Coagulation in Heart Failure: A Literature Review

PURPOSE OF REVIEW

This article summarizes the role of coagulation factors in the pathophysiology of heart failure including D-dimer, fibrinogen and fibrin, prothrombin, p-selectin, tissue factor, tissue plasminogen activator, von Willebrand factor, β-thromboglobulin, Factor XI, tissue thromboplastin, plasminogen activator inhibitor-1 (PAI-1), thrombomodulin, soluble urokinase-type plasminogen activator receptor (suPAR) and stuart-prower factor.

RECENT FINDINGS

The D-dimer, P-selectin, prothrombin, von Willebrand factor, tissue plasminogen activator, fibrinogen, suPAR, tissue factor, thrombomodulin and Factor XI play significant roles the pathophysiology of heart failure. However, no associations were found between β-thromboglobulin, tissue thromboplastin, PAI-1 and stuart-prower factor in the context of heart failure. Coagulation factors play significant role in the pathophysiology of heart failure. Consequently, the underlying pathophysiological mechanisms that explain changes in the cascade are closely related to the diagnostic, prognostic and therapeutic roles of coagulation cascade factors, which help physicians identify and treat heart failure.

Impact of Clinical Decision Support with Mandatory versus Voluntary Venous Thromboembolism Risk Assessment in Hospitalized Patients

Background  Venous thromboembolism (VTE) causes significant preventable morbidity and mortality in hospitalized patients. Assessing VTE risk is essential to initiating appropriate prophylaxis and reducing VTE outcomes. Studies show that computerized clinical decision support (CDS) can improve VTE risk assessment (RA), prophylaxis, and outcomes but few examined the effectiveness of specific design features. From 2008 to 2016, University of Michigan Health implemented CDS for VTE prevention in four stages, which alternated between voluntary and mandatory RA using the 2005 Caprini model and generated inpatient orders for risk-appropriate prophylaxis based on CHEST guidelines. This cross-sectional study evaluated the impact of mandatory versus voluntary RA on VTE prophylaxis and outcomes for adult medical and surgical patients admitted to the health system. Methods  Interrupted time series analysis was conducted to evaluate the trend in smart order set-recommended VTE prophylaxis by CDS stage. Logistic regression with CDS stage as the primary independent variable was used in pairwise comparisons of VTE during hospitalization and within 90 days post-discharge for mandatory versus voluntary RA. Adjusted odd ratios (ORs) were calculated for total, in-hospital, and post-discharge VTE. Results  In this study of 223,405 inpatients over 8 years, smart order set-recommended prophylaxis increased from 65 to 79%; it increased significantly when voluntary RA in Stage 1 became mandatory in Stage 2 (10.59%, p  < 0.001) and decreased significantly when it returned to voluntary in Stage 3 (-11.24%, p  < 0.001). The rate increased slightly when mandatory RA was reestablished in Stage 4 (0.23%, p  = 0.935). Adjusted ORs for VTE were lower for mandatory RA versus adjacent stages with voluntary RA. The adjusted OR for Stage 2 versus Stage 1 was 14% lower ( p  < 0.05) and versus Stage 3 was 11% lower ( p  < 0.05). The adjusted OR for Stage 4 versus Stage 3 was 4% lower ( p  = 0.60). These results were driven by changes in in-hospital VTE. By contrast, the incidence of post-discharge VTE increased in each successive stage. Conclusion  Mandatory RA was more effective in improving smart order set-recommended prophylaxis and VTE outcomes, particularly in-hospital VTE. Post-discharge VTE increased despite high adherence to risk-appropriate prophylaxis, indicating that guidelines for extended, post-discharge prophylaxis are needed to further reduce VTE for hospitalized patients.

Outcomes in patients discharged with extended venous thromboembolism prophylaxis after hospitalization with COVID-19

BACKGROUND

Venous thromboembolism (VTE) is a known complication of coronavirus disease (COVID-19) in patients requiring hospitalization and intensive care. We examined the association between extended pharmacological VTE prophylaxis and outcomes among patients hospitalized with COVID-19.

METHODS

This was a retrospective cohort study of patients with an index positive SARS-CoV-2 polymerase chain reaction (PCR) test at the time of, or during hospitalization. Patients who were prescribed extended pharmacological VTE prophylaxis were compared against patients who were not. Multivariable logistic regression was used to produce odds ratio (OR) estimates and Cox proportional hazard models for hazard ratios (HR) with 95% CI to examine the association between pharmacological VTE prophylaxis and outcomes of interest. Primary outcomes were 30- and 90-day VTE events. Secondary outcomes included 30- and 90-day mortality, 30-day superficial venous thrombosis (SVT), acute myocardial infarction (MI), acute ischemic stroke, critical limb ischemia, clinically significant bleeding, and inpatient readmissions.

RESULTS

A total of 1936 patients were included in the study. Among them, 731 (38%) were discharged on extended pharmacological VTE prophylaxis. No significant difference was found in 30- and 90-day VTE events among groups. Patients discharged on extended VTE prophylaxis showed improved survival at 30 (HR: 0.35; 95% CI: 0.21-0.59) and 90 days (HR: 0.36; 95% CI: 0.23-0.55) and reduced inpatient readmission at 30 days (OR: 0.12; 95% CI: 0.04-0.33) when compared to those without.

CONCLUSION

Patients discharged on extended VTE prophylaxis after hospitalization due to COVID-19 had similar thrombotic events on follow-up. However, use of extended VTE prophylaxis was associated with improved 30- and 90-day survival and reduced risk of 30-day inpatient readmission.

Impact of thromboprophylaxis on hospital acquired thrombosis following discharge in patients admitted with COVID-19: Multicentre observational study in the UK

Post-discharge thromboprophylaxis in patients admitted with COVID-19 remains controversial. We aimed to determine the impact of thromboprophylaxis on hospital acquired thrombosis (HAT) in patients (≥18 years) discharged following admission for COVID-19 in an observational study across 26 NHS Trusts in the UK (01.04.2020-31.12.2021). Overall, 8895 patients were included to the study: 971 patients were discharged with thromboprophylaxis and propensity score matched (PSM) with a desired ratio of 1:1, from patients discharged without thromboprophylaxis. Patients with heparin induced thrombocytopenia, major bleeding during admission and pregnant women were excluded. As expected from 1:1 PSM, no difference was observed in parameters between the two groups, including duration of hospital stay, except the thromboprophylaxis group had a significantly higher proportion who had received therapeutic dose anticoagulation during admission. There were no differences in the laboratory parameters especially D-dimers between the two groups at admission or discharge. Median duration of thromboprophylaxis following discharge from hospital was 4 weeks (1-8 weeks). No difference was found in HAT in patients discharged with TP versus no TP (1.3% vs. 0.92%, p = 0.52). Increasing age and smoking significantly increased the risk of HAT. Many patients in both cohorts had raised D-dimer at discharge but D-dimer was not associated with increased risk of HAT.

Predicting post-discharge venous thromboembolism and bleeding among medical patients: External validation of a novel risk score utilizing ubiquitous biomarkers

BACKGROUND

Post-hospitalization thromboprophylaxis can reduce venous thromboembolism (VTE) risk for non-surgical patients but may carry bleeding risks. We aimed to externally validate the Intermountain Risk Scores for hospital-associated venous thromboembolism (HA-VTE IMRS) and major bleeding (HA-MB IMRS) for VTE and bleeding outcomes.

METHODS

Retrospective cohort study of adult patients discharged alive from medical services between 2015 and 2019. HA-VTE IMRS and HA-MB IMRS were calculated at the time of hospital discharge and dichotomized as high- or low-risk as described in the derivation manuscript. 90-day post-discharge VTE outcomes were assessed from diagnostic radiology reports, and bleeding outcomes were assessed using ICD-10 codes and blood bank transfusion records.

RESULTS

Among 113,578 patients in the study, 66,340 patients (58.4 %) had a low-risk HA-VTE IMRS <7, versus 47,238 (41.6 %) high-risk ≥7. For bleed prediction, 71,576 patients (63 %) had a low-risk HA-MB IMRS <8, versus 42,002 (37 %) high-risk ≥8. VTE incidence was 1.1 % and 0.6 % while major bleeding incidence was 1.3 % and 0.1 % in high-risk versus low-risk cohorts, respectively. AUCs for VTE and bleed outcome discrimination were 0.59 and 0.78, respectively. Patients with a combined high-risk VTE score and low-risk bleeding score comprised 14.5 % of the population.

CONCLUSION

In this external validation study, the HA-VTE IMRS had poor discrimination for VTE but the HA-MB IMRS had good discriminatory ability for major bleeding events. A sizable minority of patients were categorized as high VTE risk with low bleed risk, a population which may have an optimal risk-benefit profile for post-hospital thromboprophylaxis.

Eligibility for Posthospitalization Venous Thromboembolism Prophylaxis in Hospitalized Patients With COVID-19: A Retrospective Cohort Study

Background

A recent randomized trial, the MICHELLE trial, demonstrated improved posthospital outcomes with a 35‐day course of prophylactic rivaroxaban for patients hospitalized with COVID‐19 at high risk of venous thromboembolism. We explored how often these findings may apply to an unselected clinical population of patients hospitalized with COVID‐19.

Methods and Results

Using a 35‐hospital retrospective cohort of patients hospitalized between March 7, 2020, and January 23, 2021, with COVID‐19 (MI‐COVID19 database), we quantified the percentage of hospitalized patients with COVID‐19 who would be eligible for rivaroxaban at discharge per MICHELLE trial criteria and report clinical event rates. The main clinical outcome was derived from the MICHELLE trial and included a composite of symptomatic venous thromboembolism, pulmonary embolus‐related death, nonhemorrhagic stroke, and cardiovascular death at 35 days. Multiple sensitivity analyses tested different eligibility and exclusion criteria definitions to determine the effect on eligibility for postdischarge anticoagulation prophylaxis. Of 2016 patients hospitalized with COVID‐19 who survived to discharge and did not have another indication for anticoagulation, 25.9% (n=523) would be eligible for postdischarge thromboprophylaxis per the MICHELLE trial criteria (range, 2.9%–39.4% on sensitivity analysis). Of the 416 who had discharge anticoagulant data collected, only 13.2% (55/416) were actually prescribed a new anticoagulant at discharge. Of patients eligible for rivaroxaban per the MICHELLE trial, the composite clinical outcome occurred in 1.2% (6/519); similar outcome rates were 5.7% and 0.63% in the MICHELLE trial's control (no anticoagulation) and intervention (rivaroxaban) groups, respectively. Symptomatic venous thromboembolism events and all‐cause mortality were 6.2% (32/519) and 5.66% in the MI‐COVID19 and MICHELLE trial control cohorts, respectively.

Conclusions

Across 35 hospitals in Michigan, ≈1 in 4 patients hospitalized with COVID‐19 would qualify for posthospital thromboprophylaxis. With only 13% of patients actually receiving postdischarge prophylaxis, there is a potential opportunity for improvement in care.

Trends in post-discharge prophylactic anticoagulant use among stroke patients in the United States between 2006 and 2019

BACKGROUND

Stroke is an independent risk factor for venous thromboembolism (VTE). Although the risk of VTE persists after hospital discharge, information on the utilization of anticoagulants among stroke patients after discharge remains limited.

OBJECTIVE

To evaluate changes in post-discharge thromboprophylaxis among stroke patients between 2006 and 2019.

METHODS

We conducted a retrospective repeated cross-sectional analysis using a commercial healthcare insurance database in the United States. We included patients aged ≥ 18 years with incident stroke diagnosis and assessed prophylactic use of anticoagulants in the 30 days following hospital discharge including low-molecular-weight heparin (enoxaparin ≤40 mg/day, dalteparin ≤5000 IU/day), unfractionated heparin ≤5000 IU/ twice daily or 3 times a day, apixaban 2.5 mg twice daily, and rivaroxaban 10 mg/day. Patients with atrial fibrillation, VTE, mechanical heart valves, cancer, antiphospholipid antibody syndrome, and users of therapeutic doses of anticoagulants were excluded. We used the Cochrane-Armitage test to assess changes in the use of anticoagulants across the study period.

RESULTS

There was a small increase in the overall use of post-discharge prophylactic anticoagulants among stroke patients between 2006 and 2019 from 0.5% to 1.9%. The use of heparin decreased from 0.5% in 2006 to 0.3% in 2019 (P-value for trend = 0.001). In contrast, the use of apixaban or rivaroxaban increased from 0.1% in 2013 to 1.6% in 2019 (P-value for trend < 0.001). Apixaban was more commonly used than rivaroxaban.

CONCLUSIONS

In this population-based study of stroke patients, we found that post-discharge anticoagulant use remains low through 2019. Prophylactic use of heparin or rivaroxaban was relatively low but the use of apixaban increased over the study period. Further research is needed to determine if these agents are safe and effective for VTE prevention in stroke patients.

Venous Thromboembolism Among Hospitalized Patients: Incidence and Adequacy of Thromboprophylaxis - A Retrospective Study

Purpose

We aimed to determine the incidence of venous thromboembolism among hospitalized patients in Qatar as well as to analyze the adequacy of VTE assessment and prophylaxis in hospitalized patients.

Design

Retrospective observational study.

Setting

Four hospitals under Hamad Medical Corporation, Qatar.

Participants

Patients over the age of 18 who were hospitalized between January 2015 and December 2019 and developed venous thromboembolism during hospitalization or within a month after discharge were included.

Results

During the study period, 641,994 individuals were admitted to hospitals. The inclusion criteria were satisfied by 209 of them. The mean age was 51.25 years and 54.5% were males. Hypertension and diabetes mellitus were the most common comorbidities found in the overall group. The incidence of VTE was 32.55 [95% CI 28.4, 37.3] per 100,000 admission per year [0.032%]. The annual incidence was least in 2015 (17.8 per 100,000 admissions) and highest in 2018 (44.4 per 100,000 admissions). Eighty-six subjects had DVT, and 109 had PE, whereas 14 had both. And, 67.5% of the patients developed VTE during admission while, 32.5% developed within 1 month of discharge. Moreover, 22.9% of the patients with PE developed pulmonary embolism after discharge from the hospital. VTE assessment was performed on 64.7% of the patients, and 69.7% received VTE prophylaxis in accordance with guidelines.

Conclusion

Although the occurrence of VTE among hospitalized patients in Qatar is low, healthcare providers need additional education and knowledge of VTE assessment and prophylaxis to follow guidelines for all patients at the time of admission. Furthermore, risk assessment for VTE should be done for all patients at the time of discharge to decide on post-discharge prophylaxis so that incidence of VTE after discharge can be minimized. Future studies should focus on patients who developed VTE after discharge from the hospital as well as on various risk factors.

Extended post-discharge thromboprophylaxis in hospitalized COVID-19 patients

INTRODUCTION

Hospitalized COVID-19 patients, particularly those with high risk features, are at risk for venous and arterial thromboembolic events for approximately 30 days or more after hospital discharge. Extended post-hospital discharge thromboprophylaxis has potential to reduce this risk.

AREAS COVERED

Recent cohort, registry, and randomized trial data on the topic of extended post-discharge thromboprophylaxis in COVID-19 inpatients are reviewed, and key patient subgroups at high thrombotic risk are highlighted, with antithrombotic guidelines on the topic discussed.

EXPERT OPINION

COVID-19 inpatients with cardiovascular risk factors, advanced age, intensive care unit stay, or an IMPROVE VTE score of 4 or more or a score of 2 or 3 plus elevated D-dimers (> twice the upper limit of normal) or an IMPROVE-DD VTE score of ≥ 4 are at high thrombotic risk in the post-discharge period. These high risk patient subgroups benefit from extended post-discharge thromboprophylaxis, specifically with rivaroxaban 10mg daily for 35 days. Recent NIH and ISTH guidelines recommend or suggest this approach. Results from other clinical trials are pending.

Racial differences in venous thromboembolism: A surveillance program in Durham County, North Carolina

Background

Venous thromboembolism (VTE) affects approximately 1-2 individuals per 1000 annually and is associated with an increased risk for pulmonary hypertension, postthrombotic syndrome, and recurrent VTE.

Objective

To determine risk factors, incidence, treatments, and outcomes of VTE through a 2-year surveillance program initiated in Durham County, North Carolina (population approximately 280,000 at time of study).

Patients/Methods

We performed a retrospective analysis of data actively collected from three hospitals in Durham County during the surveillance period.

Results

A total of 987 patients were diagnosed with VTE, for an annual rate of 1.76 per 1000 individuals. Hospital-associated VTE occurred in 167 hospitalized patients (16.9%) and 271 outpatients who were hospitalized within 90 days of diagnosis (27.5%). Annual incidence was 1.98 per 1000 Black individuals compared to 1.25 per 1000 White individuals (p < 0.0001), and Black individuals with VTE were younger than White individuals (p < 0.0001). Common risk factors included active cancer, prolonged immobility, and obesity, and approximately half were still taking anticoagulant therapy 1 year later. A total of 224 patients died by 1 year (28.5% of patients for whom outcomes could be confirmed), and Black patients were more likely to have recurrent VTE than White patients during the first 6 months following initial presentation (9.4% vs. 4.1%, p = 0.01).

Conclusions

Ongoing surveillance provides an effective strategy to identify patients with VTE and monitor treatment and outcomes. We demonstrated that hospital-associated VTE continues to be a major contributor to the burden of VTE and confirmed the higher incidence of VTE in Black compared to White individuals.

Venous thrombosis risk during and after medical and surgical hospitalizations: The medical inpatient thrombosis and hemostasis (MITH) study

BACKGROUND

Thirty to seventy percent of all venous thromboembolism (VTE) events are associated with hospitalization. The absolute and relative risks during and after hospitalization are poorly characterized.

OBJECTIVES

Quantify the absolute rate and relative risk of VTE during and up to 3 months after medical and surgical hospitalizations.

PATIENTS/METHODS

We conducted an observational cohort study between 2010 and 2016 of patients cared for by the University of Vermont (UVM) Health Network's primary care population. Cox proportional hazard models with hospitalization modeled as a time-varying covariate were used to estimate VTE risk.

RESULTS

Over 4.3 years of follow-up, 55 220 hospitalizations (156 per 1000 person-years) and 713 first venous thromboembolism events (2.0 per 1000 person-years) occurred. Among individuals not recently hospitalized, the rate of venous thromboembolism was 1.4 per 1000 person-years and 71.8 per 1000 person-years during hospitalization. During the first, second, and third months after discharge, the rates of venous thromboembolism were 35.1, 11.3, and 5.2 per 1000 person-years, respectively. Relative to those not recently hospitalized, the age- and sex-adjusted HRs of venous thromboembolism were 38.0 (95% CI 28.0, 51.5) during hospitalization, and 18.4 (95% CI 15.0, 22.6), 6.3 (95% CI 4.3, 9.0), and 3.0 (95% CI 1.7, 5.4) during the first, second, and third months after discharge, respectively. Stratified by medical versus surgical services the rates were similar.

CONCLUSION

Hospitalization and up to 3 months after discharge were strongly associated with increased venous thromboembolism risk. These data quantify this risk for use in future studies.

D-dimer and outcomes in hospitalized heart failure patients across the ejection fraction phenotypes

AIMS

The prognostic significance of D-dimer in hospitalized heart failure (HF) patients is incompletely characterized. We aimed to assess the association of D-dimer levels on admission with adverse events at follow-up in patients hospitalized with HF across all ejection fraction (EF) phenotypes.

METHODS AND RESULTS

Consecutive patients hospitalized from December 2006 to December 2017 for HF with D-dimer and EF values available (n = 1795) were enrolled. Associations between D-dimer and all-cause death were examined at 1-year follow-up. Median age was 57 years, 73.4% were male, and the majority (72.1%) were in New York Heart Association Classes III-IV. EF was reduced in 53.3% (HFrEF), mildly reduced in 16.3% (HFmrEF), and preserved in 30.4% (HFpEF). Median (interquartile range) D-dimer on admission was 0.56 (0.27-1.295) μg/mL FEU (fibrinogen-equivalent unit) in the whole cohort, 0.64 (0.28-1.48) μg/mL FEU in HFrEF, 0.50 (0.27-1.03) μg/mL FEU in HFmrEF, and 0.495 (0.25-1.10) μg/mL FEU in HFpEF (P = 0.001). At 1-year follow-up, higher D-dimer (D-dimer ≥0.56 μg/mL FEU) independently predicted all-cause death in total cohort [hazard ratio (HR) 1.55; 95% confidence interval (CI), 1.15-2.1], in HFrEF (HR, 1.49; P = 0.039), and in HFpEF (HR, 2.06; P = 0.033). However, no relationship was found for HFrEF or HFmrEF when D-dimer was treated as quartiles. In sensitivity analysis, quantitatively similar but more pronounced association between D-dimer and all-cause death was observed in total cohort and HFpEF cohort.

CONCLUSIONS

In hospitalized HF patients, higher D-dimer concentration was a significant and independent predictor of 1-year all-cause mortality. Across all HF phenotypes, this effect was most evident in HFpEF patients.

Incidence and Prognostic Implications of Readmissions Caused by Thrombotic Events After a Heart Failure Hospitalization

Background Readmission occurs in 1 out of 3 patients with heart failure (HF). We aimed to study the incidence and prognostic implications of rehospitalizations because of arterial thromboembolism events (ATEs) and venous thromboembolism events (VTEs) after discharge in patients with HF. Methods and Results We identified Medicare beneficiaries who were admitted with a primary diagnosis of HF from 2014 to 2019, with a hospital stay ranging between 3 and10 days, followed by discharge to home. We calculated incidence of ATEs (myocardial infarction, ischemic stroke, or systemic embolism) and VTEs (deep venous thrombosis and pulmonary embolism) up to 90 days after discharge. Out of 2 953 299 patients admitted with HF during the study period, a total of 585 353 patients met the inclusion criteria, and 36.6% were readmitted within 90 days of discharge. The incidence of readmission due ATEs, VTEs, HF, and all other reasons was 3.4%, 0.5%, 13.2%, and 19.5%, respectively. Incidence of thromboembolic events was highest within 14 days after discharge. Factors associated with ATEs included prior coronary, peripheral, or cerebrovascular disease and for VTEs included malignancy and prior liver or lung disease. ATE/VTE readmission had a 30-day mortality of 19.9%. After a median follow-up period of 25.6 months, ATE and VTE readmissions were associated with higher risk of mortality (hazard ratio, 2.76 [95% CI, 2.71-2.81] and 2.17 [95% CI, 2.08-2.27], respectively; P<0.001 for both) compared with no readmission on time-dependent Cox regression. Conclusions After a HF hospitalization, 3.9% of patients were readmitted with a thromboembolic event that was associated with 2- to 3-fold greater risk of mortality in follow-up.

Increased length of stay following total joint arthroplasty based on insurance type

BACKGROUND

Increased length of stay after total joint arthroplasty has been shown to be a risk factor for peri-operative complications. The purpose of this study was to determine if Medicaid insurance would be a risk factor for increased length of stay after total joint arthroplasty.

METHODS

We retrospectively reviewed a single surgeon's practice of 428 total hip and total knee arthroplasties who had insurance status of Medicaid, Medicare, Private or none. After exclusion criteria there were 400 patients. Patients with insurance status of Medicaid, Medicare or Private were then compared based on length of stay ≤ 2 days and length of stay > 2 days and then further analyzed using demographic, operative data, and total length of stay.

RESULTS

Medicaid patients had an increased length of stay compared to patients with Medicare or Private insurance [1.98 days versus 1.73 days, p = .037, 95% confidence intervals (1.78-2.18) and (1.61-1.85), respectively]. The greatest predictor of a less than two-night stay post-operatively was private insurance status (p = 0.001). Medicaid patients had a higher incidence of prescribed narcotic use pre-operatively (p = 0.013). Although not significant, a trend was noted in the Medicaid population with higher incidence of smoking (p = 0.094) and illicit drug abuse (p = 0.099) pre-operatively in this sample subset.

CONCLUSIONS

Patients with Medicaid insurance undergoing total joint arthroplasty have increased length of stay compared to patients with Medicare or Private insurance and have higher incidence of pre-operative narcotic use.

Pathogenesis of Two Faces of DVT: New Identity of Venous Thromboembolism as Combined Micro-Macrothrombosis via Unifying Mechanism Based on "Two-Path Unifying Theory" of Hemostasis and "Two-Activation Theory of the Endothelium"

Venous thrombosis includes deep venous thrombosis (DVT), venous thromboembolism (VTE), venous microthrombosis and others. Still, the pathogenesis of each venous thrombosis is not clearly established. Currently, isolated distal DVT and multiple proximal/central DVT are considered to be the same macrothrombotic disease affecting the venous system but with varying degree of clinical expression related to its localization and severity. The genesis of two phenotypes of DVT differing in clinical features and prognostic outcome can be identified by their unique hemostatic mechanisms. Two recently proposed hemostatic theories in vivo have clearly defined the character between "microthrombi" and "macrothrombus" in the vascular system. Phenotypic expression of thrombosis depends upon two major variables: (1) depth of vascular wall damage and (2) extent of the injury affecting the vascular tree system. Vascular wall injury limited to endothelial cells (ECs) in sepsis produces "disseminated" microthrombi, but intravascular injury due to trauma extending from ECs to subendothelial tissue (SET) produces "local" macrothrombus. Pathogen-induced sepsis activates the complement system leading to generalized endotheliopathy, which releases ultra large von Willebrand factor (ULVWF) multimers from ECs and promotes ULVWF path of hemostasis. In the venous system, the activated ULVWF path initiates microthrombogenesis to form platelet-ULVWF complexes, which become "microthrombi strings" that produce venous endotheliopathy-associated vascular microthrombotic disease (vEA-VMTD) and immune thrombocytopenic purpura (ITP)-like syndrome. In the arterial system, endotheliopathy produces arterial EA-VMTD (aEA-VMTD) with "life-threatening" thrombotic thrombocytopenic purpura (TTP)-like syndrome. Typically, vEA-VMTD is "silent" unless complicated by additional local venous vascular injury. A local venous vessel trauma without sepsis produces localized macrothrombosis due to activated ULVWF and tissue factor (TF) paths from damaged ECs and SET, which causes distal DVT with good prognosis. However, if a septic patient with "silent" vEA-VMTD is complicated by additional vascular injury from in-hospital vascular accesses, "venous combined micro-macrothrombosis" may develop as VTE via the unifying mechanism of the "two-path unifying theory" of hemostasis. This paradigm shifting pathogenetic difference between distal DVT and proximal/central DVT calls for a reassessment of current therapeutic approaches.

Pulmonary Embolism in Post-CoviD-19 Patients, a Literature Review: Red Flag for Increased Awareness?

Although COVID-19 was primarily considered a respiratory illness, rapidly accumulating data suggest that COVID-19 is associated with a high incidence of venous thromboembolic complications. The primary objective of this review article was to reveal whether we need to increase awareness of pulmonary embolism in the period following the COVID-19 infection given that the epidemiologic facts are still poor. A literature search and a critical review of the collected studies were conducted. An electronic search of PubMed, Science Direct Scopus, Google Scholar, and Excerpta Medica Database (EMBASE) from June 2020 until June 2022. The long-term health consequences of COVID-19 remain largely unclear. This review highlights the importance of awareness of the potentially increased incidence of venous thromboembolism in post-COVID-19 patients, even those with mild or asymptomatic disease. Further research is required to establish appropriate clinical management guidelines for the prevention of thromboembolic complications in the post-COVID-19 period.

Thrombotic and Hemorrhagic Incidences in Patients After Discharge from COVID-19 Infection: A Systematic Review and Meta-Analysis

Background

The association between coronavirus infection 2019 (COVID-19) and thrombosis has been explicitly shown through numerous reports that demonstrate high rates of thrombotic complications in infected patients. Recently, much evidence has shown that patients who survived COVID-19 might have a high thrombotic risk after hospital discharge. This current systematic review and meta-analysis was conducted to better understand the incidence of thrombosis, bleeding, and mortality rates among patients discharged after COVID-19 hospitalization.

Methods

Using a search strategy that included terms for postdischarge, thrombosis, and COVID-19, 2 investigators independently searched for published articles indexed in the MEDLINE, Embase, and Scopus databases that were published before August 2021. Pooled incidences and 95% confidence intervals were calculated using the DerSimonian-Laird random-effects model with a double arcsine transformation.

Results

Twenty articles were included in the meta-analysis. They provided a total of 19 461 patients discharged after COVID-19 hospitalization. The weighted pooled incidence of overall thrombosis among the patients was 1.3% (95 CI, 0. 6-2; I² 90.5), with a pooled incidence of venous thrombosis of 0.7% (95 CI, 0. 4-1; I² 73.9) and a pooled incidence of arterial thrombosis of 0.6% (95 CI, 0. 2-1; I² 88.1). The weighted pooled incidences of bleeding and mortality were 0.9% (95 CI, 0. 1-1.9; I² 95.1) and 2.8% (95 CI, 0. 6-5; I² 98.2), respectively.

Conclusions

The incidences of thrombosis and bleeding in patients discharged after COVID-19 hospitalization are comparable to those of medically ill patients.

Medically Ill hospitalized Patients for COVID-19 THrombosis Extended ProphyLaxis with rivaroxaban ThErapy: Rationale and Design of the MICHELLE Trial

BACKGROUND

The devastating Coronavirus disease (COVID-19) pandemic is associated with a high prothrombotic state. It is unclear if the coagulation abnormalities occur because of the direct effect of SARS-CoV-2 or indirectly by the cytokine storm and endothelial damage or by a combination of mechanisms. There is a clear indication of in-hospital pharmacological thromboprophylaxis for every patient with COVID-19 after bleed risk assessment. However, there is much debate regarding the best dosage regimen, and there is no consensus on the role of extended thromboprophylaxis.

DESIGN

This study aims to evaluate the safety and efficacy of rivaroxaban 10 mg once daily for 35 ± 4 days versus no intervention after hospital discharge in COVID-19 patients who were at increased risk for VTE and have received standard parenteral VTE prophylaxis during hospitalization. The composite efficacy endpoint is a combination of symptomatic VTE, VTE-related death, VTE detected by bilateral lower limbs venous duplex scan and computed tomography pulmonary angiogram on day 35 ± 4 posthospital discharge and symptomatic arterial thromboembolism (myocardial infarction, nonhemorrhagic stroke, major adverse limb events, and cardiovascular death) up to day 35 ± 4 posthospital discharge. The key safety outcome is the incidence of major bleeding according to ISTH criteria.

SUMMARY

The MICHELLE trial is expected to provide high-quality evidence around the role of extended thromboprophylaxis in COVID-19 and will help guide medical decisions in clinical practice.1.

Anticoagulation in COVID-19: a review of current literature and guidelines

Severe acute respiratory syndrome coronavirus 2 infections are associated with greater risk of both arterial and venous thromboembolic events.Pathophysiology and Clinical implications: This has been attributed to a florid proinflammatory state resulting in microvascular dysfunction, activation of platelets and procoagulant systems as well as possible direct endothelial injury. The associated morbidity and mortality of these events has prompted much speculation and varied anticoagulation and fibrinolytic strategies based on multiple criteria including disease severity and biomarkers. No clear definitive benefit has been established with these approaches, which have frequently led to greater bleeding complications without significant mortality benefit.Overview: In this review, we outline the burden of these thromboembolic events in coronavirus disease-2019 (COVID-19) as well as the hypothesized contributory biological mechanisms. Finally, we provide a brief overview of the major clinical studies on the topic, and end with a summary of major societal guideline recommendations on anticoagulation in COVID-19.

American Society of Hematology living guidelines on the use of anticoagulation for thromboprophylaxis in patients with COVID-19: July 2021 update on post-discharge thromboprophylaxis

Background

COVID-19–related acute illness is associated with an increased risk of venous thromboembolism (VTE).

Objective

These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in decisions about the use of anticoagulation for thromboprophylaxis in patients with COVID-19 who do not have confirmed or suspected VTE.

Methods

ASH formed a multidisciplinary guideline panel, including 3 patient representatives, and applied strategies to minimize potential bias from conflicts of interest. The McMaster University GRADE Centre supported the guideline development process, including performing systematic evidence reviews (up to March 2021). The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the grading of recommendations assessment, development, and evaluation (GRADE) approach to assess evidence and make recommendations, which were subject to public comment.

Results

The panel agreed on 1 additional recommendation. The panel issued a conditional recommendation against the use of outpatient anticoagulant prophylaxis in patients with COVID-19 who are discharged from the hospital and who do not have suspected or confirmed VTE or another indication for anticoagulation.

Conclusions

This recommendation was based on very low certainty in the evidence, underscoring the need for high-quality randomized controlled trials assessing the role of postdischarge thromboprophylaxis. Other key research priorities include better evidence on assessing risk of thrombosis and bleeding outcomes in patients with COVID-19 after hospital discharge.

Intermittent Pneumatic Compression in Addition to Standard Prophylaxis of Postoperative Venous Thromboembolism in Extremely High-risk Patients (IPC SUPER): A Randomized Controlled Trial

OBJECTIVE

To assess the efficacy of adjunctive IPC to standard prophylaxis of postoperative VTE in patients at extremely high-risk.

SUMMARY OF BACKGROUND DATA

The standard prophylaxis for postoperative VTE is insufficient in extremely high-risk patients. It is unclear whether an adjunctive use of IPC would result in a lower incidence of postoperative venous thrombosis.

METHODS

We randomly assigned patients who underwent major surgery and had a Caprini score of ≥11 to receive either IPC in addition to standard prophylaxis with anti-embolic stockings (pressure of 18-21 mm Hg at the ankle) and low-molecular-weight heparin (IPC group) or standard prophylaxis alone (control group). The primary outcome was an asymptomatic venous thrombosis of the lower limbs, as detected by duplex ultrasound scan performed before inclusion and every 3-5 days after surgery.

RESULTS

A total of 407 patients underwent randomization, of which 204 were assigned to the IPC group and 203 to the control group. The primary outcome occurred in 1 (0.5%) patient in the IPC group and 34 (16.7%) patients in the control group [relative risk, 0.03, 95% confidential interval (CI): 0.01-0.21]. Pulmonary embolism occurred in none of the 204 patients in the IPC group and in 5 (2.5%) patients in the control group (relative risk, 0.09; 95% CI, 0.01-1.63), and postoperative death occurred in 6 (2.9%) patients in the IPC group and 10 (4.9%) in the control group (relative risk, 0.50; 95% CI, 0.50-1.60).

CONCLUSIONS

Among patients with a Caprini score of ≥11 who received standard prophylaxis for VTE, adjunctive IPC resulted in a significantly lower incidence of asymptomatic venous thrombosis.

Post-discharge thrombosis and bleeding in medical patients: A novel risk score derived from ubiquitous biomarkers

BACKGROUND

Some hospitalized medical patients experience venous thromboembolism (VTE) following discharge. Prophylaxis extended beyond hospital discharge (extended duration thromboprophylaxis [EDT]) may reduce this risk. However, EDT is costly and can cause bleeding, so selecting appropriate patients is essential. We formerly reported the performance of a mortality risk prediction score (Intermountain Risk Score [IMRS]) that was minimally predictive of 90-day hospital-associated venous thromboembolism (HA-VTE) and major bleeding (HA-MB). We used the components of the IMRS to calculate de novo risk scores to predict 90-day HA-VTE (HA-VTE IMRS) and major bleeding (HA-MB IMRS).

METHODS

From 45 669 medical patients we randomly assigned 30 445 to derive the HA-VTE IMRS and the HA-MB IMRS. Backward stepwise regression and bootstrapping identified predictor covariates from the blood count and basic chemistry. These candidate variables were split into quintiles, and the referent quintile was that with the lowest event rate for HA-VTE and HA-MB; respectively. A clinically relevant rate of HA-VTE and HA-MB was used to inform outcome rates. Performance was assessed in the derivation set of 15 224 patients.

RESULTS

The HA-VTE IMRS and HA-MB IMRS area under the receiver operating curve (AUC) in the derivation set were 0.646, and 0.691, respectively. In the validation set, the HA-VTE IMRS and HA-MB IMRS AUCs were 0.60 and 0.643.

CONCLUSIONS

Risk scores derived from components of routine labs ubiquitous in clinical care identify patients that are at risk for 90-day postdischarge HA-VTE and major bleeding. This may identify a subset of patients with high HA-VTE risk and low HA-MB risk who may benefit from EDT.

A clinical focus on the use of extended-duration thromboprophylaxis in medically ill patients

PURPOSE

This review describes and analyzes literature to provide recommendations for use of extended-duration thromboprophylaxis (EDT) in medically ill patients.

SUMMARY

Guidelines recommend pharmacologic thromboprophylaxis for patients at increased thrombosis risk during hospitalization and recommend against extending thromboprophylaxis beyond hospitalization. Despite these recommendations, observational data demonstrate that venous thromboembolism (VTE) risk persists following hospital discharge. A MEDLINE literature search was performed to identify original research evaluating the safety and efficacy of EDT. Eight meta-analyses and 5 randomized controlled trials-each varying in the agents studied (enoxaparin, rivaroxaban, apixaban, and betrixaban)-were selected for inclusion. Collectively, the evaluated data demonstrates that EDT reduces the incidence of VTE at the expense of increasing the risk of major bleeding and without providing mortality reduction. Variations in enrollment criteria, differences in EDT strategies, and uncertainty regarding proper patient selection limit the applicability of EDT in practice. Rivaroxaban and betrixaban gained Food and Drug Administration (FDA) approval on the basis of results of the APEX and MARINER trials and a post hoc analysis of the MAGELLEN trial results. Although a number of agents are FDA approved for use in EDT, clinicians must carefully weigh the risks vs benefits of EDT with these agents until studies demonstrate a more favorable risk-benefit profile.

CONCLUSION

Evidence to support EDT in medically ill patients is inconclusive and has highlighted the need for an individualized approach. The reviewed evidence supports guideline recommendations from both the American College of Chest Physicians and the American Society of Hematology that recommend against routine use of EDT in the majority of medically ill patients. Future studies are needed to optimize the risk-benefit profile of EDT and to ensure proper patient selection.

A Case Series of Life-Threatening Hemorrhagic Events in Patients with COVID-19

Since venous microthrombotic and thromboembolic events in end organs have been pathophysiologically confirmed as a component of thrombo-inflammatory cascade in COVID-19 syndrome, anticoagulant prescription with prophylactic or therapeutic goal is recommended. Different guidelines for the above are introduced; however, there is no general consensus on any neither the type of anticoagulant nor for the dosage and duration of prescription. In our medical center, adopted internal guideline was considered for patients COVID-19. We consulted patients with COVID-19 who suffered from concurrent hematoma. Appropriate surgical approach was considered. Finally autopsy study was performed for patients. In this article, we presented a series of seven SARS-CoV-2 confirmed cases faced with bleeding complication following initiation of anticoagulation protocol. The rectus sheath hematoma with extension to pelvic and/or retroperitoneal space, even involving bowel mesentery was seen most commonly. Despite receiving appropriate surgical care, all seven cases died. Finally, in all cases, autopsy studies revealed no evidence for confirmation of DIC/SIC or organ failure as the reason of death although pulmonary involvement with SARS-CoV-2 and bleeding phenomena were approved. The nature of the COVID-19 syndrome makes patients vulnerable to hemorrhagic events following anticoagulant administration which relatively causes or accelerates patient's expiration.

Risk and Management of Venous Thromboembolism in Patients with COVID-19

BACKGROUND

One of the most pronounced and poorly understood pathological features of COVID-19 infection has been high risk for venous and arterial thromboembolic complications. An increasing number of thromboembolic events are being reported almost on a daily basis, and the medical community has struggled to predict and mitigate this risk. We aimed to review available literature on the risk and management of COVID-19 related venous thromboembolism (VTE), and provide evidence-based guidance to manage these events.

METHODS

A literature review of VTE complications in patients with COVID-19 was performed, in addition to a summary of the societal guidelines and present pathways implemented at our institution for the management of both in- and outpatient COVID-19 related VTE.

RESULTS

Although a significant VTE risk has been confirmed in patients with COVID-19, literature addressing best ways to mitigate this risk is lacking. Furthermore, there has been very limited guidance provided by societal guidelines to help prevent and manage VTE associated with the COVID-19 infection. In light of the available data, we advise that all patients admitted with suspected or confirmed COVID-19 receive pharmacological prophylaxis if bleeding risk is acceptable. For patients with COVID-19 who have been discharged from the emergency department or hospital, we suggest extended thromboprophylaxis (up to 39 days) as long as bleeding risk is low.

CONCLUSIONS

We believe that this literature summary along with our center recommendations and algorithms provide valuable guidance to providers caring for patients with COVID-19 related VTE. More research is needed to standardize prophylaxis and management protocols for these patients.

Extended duration venous thromboembolism prophylaxis with betrixaban for patients re-admitted with venous thromboembolism

Patients hospitalized for an acute medical illness remain at risk of developing venous thromboembolism (VTE) post-discharge. Betrixaban, an oral direct Factor Xa inhibitor, is approved for extended VTE thromboprophylaxis in acutely ill medical patients. The primary objective of this study was to evaluate patients re-admitted with VTE within 30 days of discharge to determine if they would have been eligible for extended duration VTE prophylaxis during the index admission. We used three different sets of eligibility criteria: the APEX study criteria, the Bevyxxa® (betrixaban) package insert, and Mass General Brigham HealthCare System's Center for Drug Policy Guidelines. A secondary aim was to describe the reasons for ineligibility. Within 30 days of the index hospital admission, 226 patients were re-admitted with new VTE between January 2017 and December 2018. Of these, 134 (59%) were excluded based on pre-defined exclusion criteria. Of the remaining 92, 22 patients (23.9%) were eligible based on the APEX study criteria, 26 patients (28.2%) based on Mass General Brigham HealthCare System's Center for Drug Policy Guidelines, and 92 patients (100%) based on the Bevyxxa® package insert. There were 22 patients (23.9%) who were eligible for VTE prophylaxis with betrixaban based on all three criteria. Appropriate betrixaban use may have prevented some of the VTE events and re-admissions that occurred within 30 days of initial hospital discharge.

Impact of a clinical pharmacist on ultrasound-guided venous thromboembolism screening in hospitalized COVID-19 patients: a pilot prospective study

Background

The recognition, prevention and treatment of venous thromboembolism (VTE) remains a major challenge in the face of the recent COVID-19 pandemic which has been associated with significant cardiovascular, renal, respiratory and hematologic complications related to hypercoagulability. There has been little literature thus far on the utility of screening ultrasound and the role of the clinical pharmacist in treating these patients.

Methods

We present a prospective pilot program of thirty-one consecutive COVID-19 patients who were provided four extremity screening ultrasounds for VTE on admission. This was coordinated by a clinical pharmacist as part of a multidisciplinary approach. Quantitative and qualitative data were recorded with the goal of describing the utility of the clinical pharmacist in ultrasound screening. Data collected include demographics, information on clinical symptoms or signs at presentation, and laboratory and radiologic results during the hospitalization from each individual electronic medical record.

Results

Nine of the thirty-one patients presented with VTE. Of the nine patients, there were twenty-two total clotted vessels, all of which were asymptomatic. The clinical pharmacist, as the coordinator for a multidisciplinary COVID-19 associated coagulopathy management team, drafted a screening and treatment protocol for anticoagulation prophylaxis and therapy of VTE after ultrasound findings.

Conclusion

VTE screening of hospitalized COVID-19 patients reveals a significant number of asymptomatic VTEs and justifies diagnostic, prophylactic, and treatment measures coordinated by a clinical pharmacist.

Performance of the Wells score in predicting deep vein thrombosis in medical and surgical hospitalized patients with or without thromboprophylaxis: The R-WITT study

The Wells score had shown weak performance to determine pre-test probability of deep vein thrombosis (DVT) for inpatients. So, we evaluated the impact of thromboprophylaxis on the utility of the Wells score for risk stratification of inpatients with suspected DVT. This bicentric cross-sectional study from February 1, 2018 to January 31, 2019 included consecutive medical and surgical inpatients who underwent lower limb ultrasound study for suspected DVT. Wells score clinical predictors were assessed by both ordering and vascular physicians within 24 h after clinical suspicion of DVT. Primary outcome was the Wells score's accuracy for pre-test risk stratification of suspected DVT, accounting for anticoagulation (AC) treatment (thromboprophylaxis for ⩾ 72 hours or long-term anticoagulation). We compared prevalence of proximal DVT among the low, moderate and high pre-test probability groups. The discrimination accuracy was defined as area under the receiver operating characteristics (ROC) curve. Of the 415 included patients, 30 (7.2%) had proximal DVT. Prevalence of proximal DVT was lower than expected in all pre-test probability groups. The prevalence in low, moderate and high pre-test probability groups was 0.0%, 3.1% and 8.2% (p = 0.22) and 1.7%, 4.2% and 25.8% (p < 0.001) for inpatients with or without AC, respectively. Area under ROC curves for discriminatory accuracy of the Wells score, for risk of proximal DVT with or without AC, was 0.72 and 0.88, respectively. The Wells score performed poorly for discrimination of risk for proximal DVT in hospitalized patients with AC but performed reasonably well among patients without AC; and showed low inter-rater reliability between physicians. ClinicalTrials.gov Identifier: NCT03784937.

Post-hospital discharge venous thromboembolism prophylaxis in medically ill patients

There is a widely expressed concern about an unmet need for post hospitalization venous thromboembolism (VTE) prophylaxis in medically ill patients, however, physicians and hospitals have been slow to implement this measure. Recommendations against extended VTE prophylaxis in medical patients from the American Society of Hematology (ASH) in 2018 and the withholding of approval of betrixiban by the European Medicines Agency also in 2018 may have been influential in this regard. Furthermore, rivaroxaban the other drug approved for this indication in the U.S has not yet been approved in Europe. In addition, hospital administrators, those monitoring expenses in the U.S, have been reluctant to support a treatment which will mostly involve outpatients. Internal medicine physicians, hospitalists and nursing home physicians have not shared the fervor for post hospital VTE prophylaxis, whether with anticoagulants or aspirin, that their orthopedic surgery colleagues have, particularly in hip and knee arthroplasty. This is despite an increased risk of post hospital discharge thrombosis in both groups of patients. Enter hospitalized patients with COVID-19, a potentially severe medical illness with high hospitalization related thrombosis risk, and questions arise as to whether these medical patients, who are clearly more hypercoagulable during hospitalization than those in previous studies, should warrant post hospital discharge prophylaxis.

Prevention of Venous Thromboembolism in Acutely Ill Medical Patients: A New Era

Venous thromboembolism (VTE) is the leading preventable cause of death in hospitalized patients and data consistently show that acutely ill medical patients remain at increased risk for VTE-related morbidity and mortality in the post-hospital discharge period. Prescribing extended thromboprophylaxis for up to 45 days following an acute hospitalization in key patient subgroups that include more than one-quarter of hospitalized medically-ill patients represents a paradigm shift in the way hospital-based physicians think about VTE prevention. Advances in the field of primary thromboprophylaxis in acutely-ill medical patients using validated VTE and bleeding risk assessment models have established key patient subgroups at high risk of VTE and low risk of bleeding that may benefit from both in-hospital and extended thromboprophylaxis. The direct oral anticoagulants betrixaban and rivaroxaban are now U.S. Food and Drug Administration-approved for in-hospital and extended thromboprophylaxis in medically ill patients and provide net clinical benefit in these key subgroups. Coronavirus disease-2019 may predispose patients to VTE due to excessive inflammation, platelet activation, endothelial dysfunction, and hemostasis. The optimum preventive strategy for these patients requires further investigation. This article aims to review the latest concepts in predicting and preventing VTE and discuss the new era of extended thromboprophylaxis in hospitalized medically ill patients.

Extended duration of thromboprophylaxis for medically ill patients: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

The benefit of extended-duration thromboprophylaxis in patients hospitalised for acute medical illness beyond hospital stay remains controversial.

AIMS

To perform a meta-analysis of randomised controlled trials (RCT) in order to examine the efficacy and safety of extended-duration anticoagulation for venous-thromboembolism (VTE) prophylaxis in this high-risk population.

METHODS

An electronic database search was conducted to include all RCT comparing between extended-duration versus short-duration prophylactic anticoagulation in medically ill patients. The primary efficacy outcome was the composite events of asymptomatic deep vein thrombosis (DVT), symptomatic VTE and death from VTE-related causes.

RESULTS

Five RCT were included totalling 40 124 patients, with a mean age of 71 years and 51% were male. In comparison to standard-duration therapy, extended-duration thromboprophylaxis was associated with a significant reduction in the primary efficacy outcome (risk ratio (RR) 0.75; 95% confidence interval (CI) 0.67-0.85; P < 0.01), symptomatic VTE (RR 0.53; 95% CI 0.33-0.84; P < 0.01) and asymptomatic DVT (RR 0.81; 95% CI 0.71-0.94; P < 0.01). However, there were no significant differences between both groups with regard to VTE-related death (RR 0.81; 95% CI 0.60-1.10; P = 0.18) or all-cause death (RR 0.97; 95% CI 0.88-1.08; P = 0.64). In contrast, extended-duration thromboprophylaxis was associated with an increased risk of major bleeding (RR 2.04; 95% CI 1.42-2.91; P < 0.01) and non-major clinically relevant bleeding (RR 1.81; 95% CI 1.29-2.53; P < 0.01).

CONCLUSIONS

Among hospitalised medically ill patients, prolonging venous thromboprophylaxis was associated with a decreased risk of composite events of the primary efficacy outcome and increased risk of bleeding with no significant difference in VTE-related death.

Post-Discharge Prophylaxis With Rivaroxaban Reduces Fatal and Major Thromboembolic Events in Medically Ill Patients

Background

Hospitalized acutely ill medical patients are at risk for fatal and major thromboembolic events. Whether use of extended-duration primary thromboprophylaxis can prevent such events is unknown.

Objectives

The purpose of this study was to evaluate whether extended-duration rivaroxaban reduces the risk of venous and arterial fatal and major thromboembolic events without significantly increasing major bleeding in acutely ill medical patients after discharge.

Methods

MARINER (A Study of Rivaroxaban [JNJ-39039039] on the Venous Thromboembolic Risk in Post-Hospital Discharge Patients) studied acutely ill medical patients with additional risk factors for venous thromboembolism (VTE). Medically ill patients with a baseline creatinine clearance ≥50 ml/min were randomized in a double-blind fashion to rivaroxaban 10 mg or placebo daily at hospital discharge for 45 days. Exploratory efficacy analyses were performed with the intent-to-treat population including all data through day 45. Time-to-event curves were calculated using the Kaplan-Meier method. A blinded independent committee adjudicated all clinical events.

Results

In total, 4,909 patients were assigned to rivaroxaban and 4,913 patients to placebo. The mean age was 67.8 years, 55.5% were men, mean baseline creatinine clearance was 87.8 ml/min, and mean duration of hospitalization was 6.7 days. The pre-specified composite efficacy endpoint (symptomatic VTE, myocardial infarction, nonhemorrhagic stroke, and cardiovascular death) occurred in 1.28% and 1.77% of patients in the rivaroxaban and placebo groups, respectively (hazard ratio: 0.72; 95% confidence interval: 0.52 to 1.00; p = 0.049), whereas major bleeding occurred in 0.27% and 0.18% of patients in the rivaroxaban and placebo groups, respectively (hazard ratio: 1.44; 95% confidence interval: 0.62 to 3.37; p = 0.398).

Conclusions

Extended-duration rivaroxaban in hospitalized medically ill patients resulted in a 28% reduction in fatal and major thromboembolic events without a significant increase in major bleeding. (A Study of Rivaroxaban [JNJ-39039039] on the Venous Thromboembolic Risk in Post-Hospital Discharge Patients [MARINER]; NCT02111564)

Prevalence of asymptomatic deep vein thrombosis in patients hospitalized with SARS-CoV-2 pneumonia: a cross-sectional study

The association between coronavirus disease 2019 (COVID-19) pneumonia and venous thrombotic disorders is still unclear. We assessed the association between COVID-19 infection-related pneumonia and proximal deep-vein thrombosis (DVT) in a cohort of patients admitted to our hospital during the European outbreak in the front line of Cremona, Lombardy. In a single-center cross-sectional study, all patients hospitalized for more than 5 days in Internal Medicine Department with confirmed COVID-19 pneumonia received 2-point compressive ultrasound assessment (CUS) of the leg vein system during a single day. Ninety-four percent of patients received enoxaparin as standard pharmacological prophylaxis for venous thromboembolism. The presence of DVT was defined as incompressibility of popliteal or common femoral vein. Out of 121 patients with COVID-19 pneumonia (mean age 71.8, 66.3% males) hospitalized on March 31st, 70 stayed in hospital for over 5 days and 66 of them underwent CUS of deep venous system of the legs. The presence of asymptomatic DVT was found in 9 patients (13.6%). No symptomatic DVT was found. Patients with DVT showed mean age = 75.7 years, mean D-dimer levels = 4.02 ng/ml and all of them received enoxaparin for thromboprophylaxis, except one. Computed tomography pulmonary angiogram confirmed pulmonary embolism in five patients. One every seven patients with COVID-19-related pneumonia, hospitalized for more than 5 days, had asymptomatic proximal DVT and half of them had confirmed PE despite standard pharmacological thromboprophylaxis. This observational study suggests the need of an active surveillance through CUS in patients hospitalized with acute SARS-COV-2 and underline the need of a more intense thromboprophylaxis.

Postdischarge thrombosis and hemorrhage in patients with COVID-19

Coronavirus disease 2019 (COVID-19) is associated with a prothrombotic state with a high incidence of thrombotic events during hospitalization; however, data examining rates of thrombosis after discharge are limited. We conducted a retrospective observational cohort study of discharged patients with confirmed COVID-19 not receiving anticoagulation. The cohort included 163 patients with median time from discharge to last recorded follow-up of 30 days (interquartile range [IQR], 17-46 days). The median duration of index hospitalization was 6 days (IQR, 3-12 days) and 26% required intensive care. The cumulative incidence of thrombosis (including arterial and venous events) at day 30 following discharge was 2.5% (95% confidence interval [CI], 0.8-7.6); the cumulative incidence of venous thromboembolism alone at day 30 postdischarge was 0.6% (95% CI, 0.1-4.6). The 30-day cumulative incidence of major hemorrhage was 0.7% (95% CI, 0.1-5.1) and of clinically relevant nonmajor bleeds was 2.9% (95% CI, 1.0-9.1). We conclude that the rates of thrombosis and hemorrhage appear to be similar following hospital discharge for COVID-19, emphasizing the need for randomized data to inform recommendations for universal postdischarge thromboprophylaxis.

Factors Influencing Prescribers' Decision for Extending Venous Thromboembolism Prophylaxis in the Medical Patient Population following Hospitalization

Introduction  Venous thromboembolism (VTE) prophylaxis during hospitalization has clearly defined metrics for risk stratification and practice policy employed to ensure processes of adherence. However, acceptance for practice or even the level and timeline of risk is less clear during the immediate time after hospitalization. With emerging new oral anticoagulant agents, data are available that may influence prescribing in the outpatient setting following hospitalization. A survey was created to determine the level of acceptance or influences for practice surrounding continuation of anticoagulation following hospitalization.

Methods  This study was designed as a single-center survey of hospitalist and family medicine physician to assess influences to the physician's impression for risk of VTE prophylaxis and knowledge of therapy options.

Results  Physicians reported depending heavily on medical center protocols for determining anticoagulation at hospital discharge. Prescribing postdischarge anticoagulation was reported to be affected by lack of comfort with prescribing oral medications and concerns with risk of bleeding for all types of anticoagulation outweighing the perceived benefit. Additionally, the decision whether to prescribe these medications at discharge was reported to be related to perceived cost and other patient barriers such as concerns over route of administration.

Conclusion  Concerns for bleeding were an influence and likely resulted in shorter duration for VTE prophylaxis being prescribed posthospitalization.

Prevention, Diagnosis, and Treatment of VTE in Patients With Coronavirus Disease 2019: CHEST Guideline and Expert Panel Report

BACKGROUND

Emerging evidence shows that severe coronavirus disease 2019 (COVID-19) can be complicated by a significant coagulopathy, that likely manifests in the form of both microthrombosis and VTE. This recognition has led to the urgent need for practical guidance regarding prevention, diagnosis, and treatment of VTE.

METHODS

A group of approved panelists developed key clinical questions by using the PICO (Population, Intervention, Comparator, Outcome) format that addressed urgent clinical questions regarding the prevention, diagnosis, and treatment of VTE in patients with COVID-19. MEDLINE (via PubMed or Ovid), Embase, and Cochrane Controlled Register of Trials were systematically searched for relevant literature, and references were screened for inclusion. Validated evaluation tools were used to grade the level of evidence to support each recommendation. When evidence did not exist, guidance was developed based on consensus using the modified Delphi process.

RESULTS

The systematic review and critical analysis of the literature based on 13 Population, Intervention, Comparator, Outcome questions resulted in 22 statements. Very little evidence exists in the COVID-19 population. The panel thus used expert consensus and existing evidence-based guidelines to craft the guidance statements.

CONCLUSIONS

The evidence on the optimal strategies to prevent, diagnose, and treat VTE in patients with COVID-19 is sparse but rapidly evolving.

Venous Thromboembolism among Hospitalized Patients with COVID-19 Undergoing Thromboprophylaxis: A Systematic Review and Meta-Analysis

Background: Preliminary evidence indicates that prophylactic-dose thromboprophylaxis may be inadequate to control the increased risk of venous thromboembolism (VTE) in patients hospitalized for coronavirus disease 2019 (COVID-19) infection. Additionally, it remains unclear whether the D-dimer measurement is useful for VTE risk stratification among COVID-19 patients. This study aimed to offer benchmark data on the incidence of VTE and to examine the difference in D-dimer levels among anticoagulated COVID-19 patients with and without VTE incident. Methods: A comprehensive literature review of PubMed from inception to May 2020 was performed for original studies that reported the frequency of VTE and death among COVID-19 patients who received thromboprophylaxis on hospitalization. The endpoints included VTE (a composite of pulmonary embolism (PE) or deep vein thrombosis (DVT)), PE, DVT, and mortality. Results: A total of 11 cohort studies were included. Among hospitalized COVID-19 patients, 23.9% (95% confidence interval (CI), 16.2% to 33.7%; I² = 93%) developed VTE despite anticoagulation. PE and DVT were detected in 11.6% (95% CI, 7.5% to 17.5%; I² = 92%) and 11.9% (95% CI, 6.3% to 21.3%; I² = 93%) of patients, respectively. Patients in the intensive care unit (ICU) had a higher risk for VTE (30.4% )95% CI, 19.6% to 43.9%)) than those in the ward (13.0% (95% CI, 5.9% to 26.3%)). The mortality was estimated at 21.3% (95% CI, 17.0% to 26.4%; I² = 53%). COVID-19 patients who developed VTE had higher D-dimer levels than those who did not develop VTE (mean difference, 2.05 µg/mL; 95% CI, 0.30 to 3.80 µg/mL; P = 0.02). Conclusions: The heightened and heterogeneous risk of VTE in COVID-19 despite prophylactic anticoagulation calls into research on the pathogenesis of thromboembolic complications and strategy of thromboprophylaxis and risk stratification. Prominent elevation of D-dimer may be associated with VTE development and can be used to identify high-risk subsets.

Anticoagulation practice patterns in COVID-19: A global survey

Background

Best practice for prevention, diagnosis, and management of venous thromboembolism (VTE) in patients with coronavirus disease 2019 (COVID-19) is unknown due to limited published data in this population.

Objectives

We aimed to assess current global practice and experience in management of COVID-19-associated coagulopathy to identify information to guide prospective and randomized studies.

Methods

Physicians were queried about their current approach to prophylaxis, diagnosis, and treatment of VTE in patients with COVID-19 using an online survey tool distributed through multiple international organizations between April 10 and 14, 2020.

Results

Five hundred fifteen physicians from 41 countries responded. The majority of respondents (78%) recommended prophylactic anticoagulation for all hospitalized patients with COVID-19, with most recommending use of low-molecular-weight heparin or unfractionated heparin. Significant practice variation was found regarding the need for dose escalation of anticoagulation outside the setting of confirmed or suspected VTE. Respondents reported the use of bedside testing when unable to perform standard diagnostic imaging for diagnosis of VTE. Two hundred ninety-one respondents reported observing thrombotic complications in their patients, with 64% noting that the complication was pulmonary embolism. Of the 44% of respondents who estimated incidence of thrombosis in patients with COVID-19 in their hospital, estimates ranged widely from 1% to 50%. One hundred seventy-four respondents noted bleeding complications (34% minor bleeding, 14% clinically relevant nonmajor bleeding, and 12% major bleeding).

Conclusion

Well-designed epidemiologic studies are urgently needed to understand the incidence and risk factors of VTE and bleeding complications in patients with COVID-19. Randomized clinical trials addressing use of anticoagulation are also needed.

Prevention of Venous Thromboembolism in 2020 and Beyond

Venous thromboembolism (VTE) is the third most common cause of vascular mortality worldwide and comprises deep-vein thrombosis (DVT) and pulmonary embolism (PE). In this review, we discuss how an understanding of VTE epidemiology and the results of thromboprophylaxis trials have shaped the current approach to VTE prevention. We will discuss modern thromboprophylaxis as it pertains to genetic risk factors, exogenous hormonal therapies, pregnancy, surgery, medical hospitalization, cancer, and what is known thus far about VTE in COVID-19 infection.

How to Build the Plane While Flying: VTE/PE Thromboprophylaxis Clinical Guidelines for COVID-19 Patients

Over the years, the practice of medicine has evolved from authority-based to experience-based to evidence-based with the introduction of the scientific process, clinical trials, and outcomes-based data analysis (Tebala GD. Int J Med Sci. 2018;15(12):1397-1405). The time required to perform the necessary randomized controlled trials, a systematic literature review, and meta-analysis of these trials to then create, accept, promulgate, and educate the practicing clinicians to use the evidence-based clinical guidelines is typically measured in years. When the severe acute respiratory syndrome novel coronavirus-2 (SARS-nCoV-2) pandemic commenced in Wuhan, China at the end of 2019, there were few available clinical guidelines to deploy, let alone adapt and adopt to treat the surge of coronavirus disease 2019 (COVID-19) patients. The aim of this study is to first explain how clinical guidelines, on which bedside clinicians have grown accustomed, can be created in the midst of a pandemic, with an evolving scientific understanding of the pathophysiology of the hypercoagulable state. The second is to adapt and adopt current venous thromboembolism diagnostic and treatment guidelines, while relying on the limited available observational reporting of COVID-19 patients to create a comprehensive clinical guideline to treat COVID-19 patients.

Acute Venous Thromboembolism Risk Highest Within 60 Days After Discharge From the Hospital in Patients With Inflammatory Bowel Diseases

BACKGROUND & AIMS

Patients with inflammatory bowel diseases (IBDs) have a high risk of venous thromboembolism (VTE). We assessed the timing and risk factors associated with readmission to the hospital for VTE among patients with IBD.

METHODS

We collected data from the Nationwide Readmissions Database on IBD index admissions resulting in readmission to the hospital for VTE within 60 days, from 2010 through 2014. We used univariable and multivariable regression to assess risk factors associated with VTE readmission with unadjusted risk ratio (RR) and adjusted RR (aRR) as measures of effect. Time to VTE readmission was assessed in 10-day intervals, for up to 90 days.

RESULTS

We identified 872,122 index admissions of patients with IBD; 1160 resulted in readmission with VTE. More than 90% of readmissions occurred within 60 days of discharge from the index admission. Factors associated with hospital readmission with VTE included prior VTE, longer length of hospital stay, comorbidities, having a flexible sigmoidoscopy or colonoscopy at index admission, and age older than 18 years. Additional risk factors included Clostridium difficile infection at index admission (aRR, 1.47; 95% CI, 1.17-1.85) and discharge to a skilled nursing facility or intermediate care facility (aRR, 1.39; 95% CI, 1.14-1.70) or discharge with home health services (aRR, 1.65; 95% CI, 1.41-1.94).

CONCLUSIONS

Among patients admitted to the hospital with IBD, most readmissions with VTE occur within 60 days of discharge. Readmission with VTE is associated with C difficile infection and discharge to a skilled nursing facility, intermediate care facility, or with home health services. Studies are needed to evaluate the potential benefit of extending VTE prophylaxis for patients admitted to the hospital with IBD for up to 2 months after discharge, to minimize risk.

Extended Venous Thromboembolism Prophylaxis in Medically Ill Patients: An NATF Anticoagulation Action Initiative

Hospitalized patients with acute medical illnesses are at risk for venous thromboembolism (VTE) during and after a hospital stay. Risk factors include physical immobilization and underlying pathophysiologic processes that activate the coagulation pathway and are still present after discharge. Strategies for optimal pharmacologic VTE thromboprophylaxis are evolving, and recommendations for VTE prophylaxis can be further refined to protect high-risk patients after hospital discharge. An early study of extended VTE prophylaxis with a parenteral agent in medically ill patients yielded inconclusive results with regard to efficacy and bleeding. In the Acute Medically Ill VTE Prevention with Extended Duration Betrixaban (APEX) trial, extended use of betrixaban halved symptomatic VTE, decreased hospital readmission, and reduced stroke and major adverse cardiovascular events compared with standard enoxaparin prophylaxis. Based on findings from APEX, the Food and Drug Administration approved betrixaban in 2017 for extended VTE prophylaxis in acute medically ill patients. In the Reducing Post-Discharge Venous Thrombo-Embolism Risk (MARINER) study, extended use of rivaroxaban halved symptomatic VTE in high-risk medical patients compared with placebo. In 2019, rivaroxaban was approved for extended thromboprophylaxis in high-risk medical patients, thus making available a new strategy for in-hospital and post-discharge VTE prevention. To address the critical unmet need for VTE prophylaxis in medically ill patients at the time of hospital discharge, the North American Thrombosis Forum (NATF) is launching the Anticoagulation Action Initiative, a comprehensive consensus document that provides practical guidance and straightforward, patient-centered recommendations for VTE prevention during hospitalization and after discharge.

New Paradigms of Extended Thromboprophylaxis in Medically Ill Patients

Extended thromboprophylaxis given to medically ill patients for up to 45 days following an acute hospitalization remains an emerging topic among many hospital-based health care providers. Recent advancements in the field of extended thromboprophylaxis using risk stratification and careful patient selection criteria have led to an improved safety profile of direct oral anticoagulants (DOACs) and established net clinical benefit when given to key patient subgroups at high risk of venous thromboembolism (VTE) and low risk of bleeding. The Food and Drug Administration (FDA) has now approved the DOACs betrixaban and rivaroxaban for both in-hospital and extended thromboprophylaxis in medically ill patients in these key subgroups, which represents more than one-quarter of hospitalized medically ill patients. This has potential to significantly reduce VTE-related morbidity and mortality for these patients. Emerging data also supports reductions in the risk of arterial thromboembolism in medically ill patients with extended thromboprophylaxis post-hospital discharge using DOACs. This article aims to review the most recent concepts of predicting and preventing VTE and to discuss emerging paradigms of extended thromboprophylaxis in hospitalized medically ill patients utilizing an individualized, risk-adapted approach.