Incidence of deep vein thrombosis through an ultrasound surveillance protocol in patients with COVID-19 pneumonia in non-ICU setting: A multicenter prospective study

The Role of POCUS to Face COVID-19: A Narrative Review

COVID-19 has been a challenging outbreak to face, with millions of deaths among the globe. Acute respiratory failure due to interstitial pneumonia was the leading cause of death other than prothrombotic activation and complications. Lung ultrasound (LUS) and point-of-care ultrasound (POCUS) are widely used not only to triage, to identify, and to monitor lungs involvement but also to assess hemodynamic status and thrombotic and hemorrhagic complications, mainly in critically ill patients. POCUS has gained growing consideration due to its bedside utilization, reliability, and reproducibility even in emergency settings especially in unstable patients. In this narrative review, we aim to describe LUS and POCUS utilization in COVID-19 infection based on the literature found on this topic. We reported the LUS patterns of COVID-19 pulmonary infection, the diagnostic accuracy with respect to CT lung scan, its prognostic value, the variety of scores and protocols proposed, and the utilization of POCUS to investigate the extra-lung complications.

Exploring heterogeneity in reported venous thromboembolism risk in COVID-19 and comparison to other viral pneumonias: a systematic review and meta-regression

Background

Sources of heterogeneity in venous thromboembolism (VTE) risk in COVID-19 are unclear and comparisons to other viruses are lacking.

Objectives

To describe VTE risk in patients with COVID-19, explore sources of heterogeneity, and make comparisons with other viral pneumonia.

Methods

PubMed and Embase data were searched on March 14, 2021, for studies on VTE in adults hospitalized with viral pneumonia. VTE risk estimates were pooled in a random effects meta-analysis stratified by virus type. Heterogeneity in COVID-19 was explored in multivariable meta-regression.

Results

Seventy studies in COVID-19 (intensive care [ICU] [47] vs ward [23]), 4 studies in seasonal influenza (ICU [3] vs ward [1]), 2 ICU studies in H1N1 and 1 ICU study in SARS-CoV-1 were included. For COVID-19 ICU, pooled VTE risk was 19.6% (95% confidence interval [CI], 16.2%-23.5; I2 = 92.8%) for nonscreening studies and 30.0% (95% CI, 17.9%-45.7%; I2 = 81.9%) for screening studies. For COVID-19 ward, pooled VTE risk was 3.4% (95% CI, 2.4%-4.7%; I2 = 91.3%) and 22.5% (95% CI, 10.2%-42.7%; I2 = 91.6%) for nonscreening and screening studies, respectively. Higher sample size was associated with lower VTE risk. Pooled VTE risk in seasonal influenza and H1N1 at ICU were 9.0% (95% CI, 5.6%-14.2%; I2 = 39.7%) and 29.2% (95% CI, 8.7%-64.2%; I2 = 77.9%), respectively. At ward, VTE risk of seasonal influenza was 2.4% (95% CI, 2.1%-2.7%). In SARS-CoV-1, VTE risk was 47.8% (95% CI, 34.0-62.0).

Conclusion

Pooled risk estimates in COVID-19 should be interpreted cautiously as a high degree of heterogeneity is present, which hinders comparison to other viral pneumonia. The association of VTE risk in COVID-19 to sample size suggests publication bias.

Incidence of lower limb deep vein thrombosis in patients with COVID-19 pneumonia through different waves of SARS-CoV-2 pandemic: A multicenter prospective study

OBJECTIVE

The aim of this study was to evaluate the incidence of deep vein thrombosis (DVT) of the lower limbs in patients hospitalized with COVID-19 pneumonia in a non-ICU setting according to the different waves of the SARS-CoV-2 pandemic.

METHODS

Multicenter, prospective study of patients with COVID-19 pneumonia admitted to Internal Medicine units in Italy during the first (March-May 2020) and subsequent waves (November 2020 -April 2021) of the pandemic using a serial compression ultrasound (CUS) surveillance to detect DVT of the lower limbs.

RESULTS

Three-hundred-sixty-three consecutive patients were enrolled. The pooled incidence of DVT was 8%: 13.5% in the first wave, and 4.2% in the subsequent waves (p = 0.002). The proportion of patients with early (< 4 days) detection of DVT was higher in patients during the first wave with respect to those of subsequent waves (8.1% vs 1.9%; p = 0.004). Patients enrolled in different waves had similar clinical characteristics, and thrombotic risk profile. Less patients during the first wave received intermediate/high dose anticoagulation with respect to those of the subsequent waves (40.5% vs 54.5%; p = 0.005); there was a significant difference in anticoagulant regimen and initiation of thromboprophylaxis at home (8.1% vs 25.1%; p<0.001).

CONCLUSIONS

In acutely ill patients with COVID-19 pneumonia, the incidence of DVT of the lower limbs showed a 3-fold decrease during the first with respect to the subsequent waves of the pandemic. A significant increase in thromboprophylaxis initiation prior to hospitalization, and the increase of the intensity of anticoagulation during hospitalization, likely, played a relevant role to explain this observation.

Delayed onset phlegmasia cerulea dolens post-SARS-CoV-2 infection treated with minimally invasive clot retrieval technology

Coronavirus disease 2019 is associated with a significant venous thromboembolic risk. Phlegmasia cerulean dolens is a severe form of deep vein thrombosis that can lead to acute limb ischemia. In this report, we present a 58-year-old woman who developed a delayed-onset left lower extremity phlegmasia cerulean dolens 8 weeks after coronavirus disease 2019 onset that led to compartment syndrome and acute limb ischemia from external compression of the arterial vasculature from edematous muscle. The patient received an emergent minimally invasive percutaneous mechanical thrombectomy and four-compartment fasciotomy, resulting in adequate perfusion and ultimately made a full recovery.

High risk of secondary infections following thrombotic complications in patients with COVID-19

Background

This study’s primary aim was to evaluate the impact of thrombotic complications on the development of secondary infections. The secondary aim was to compare the etiology of secondary infections in patients with and without thrombotic complications.

Methods

This was a cohort study (NCT04318366) of coronavirus disease 2019 (COVID-19) patients hospitalized at IRCCS San Raffaele Hospital between February 25 and June 30, 2020. Incidence rates (IRs) were calculated by univariable Poisson regression as the number of cases per 1000 person-days of follow-up (PDFU) with 95% confidence intervals. The cumulative incidence functions of secondary infections according to thrombotic complications were compared with Gray's method accounting for competing risk of death. A multivariable Fine-Gray model was applied to assess factors associated with risk of secondary infections.

Results

Overall, 109/904 patients had 176 secondary infections (IR, 10.0; 95% CI, 8.8–11.5; per 1000-PDFU). The IRs of secondary infections among patients with or without thrombotic complications were 15.0 (95% CI, 10.7–21.0) and 9.3 (95% CI, 7.9–11.0) per 1000-PDFU, respectively (P = .017). At multivariable analysis, thrombotic complications were associated with the development of secondary infections (subdistribution hazard ratio, 1.788; 95% CI, 1.018–3.140; P = .043). The etiology of secondary infections was similar in patients with and without thrombotic complications.

Conclusions

In patients with COVID-19, thrombotic complications were associated with a high risk of secondary infections.

Compressive ultrasound can predict early pulmonary embolism onset in COVID patients

PURPOSE

To evaluate the usefulness of compressive ultrasound (CUS) for the diagnosis of deep vein thrombosis (DVT) in patients with SARS-CoV-2-related infection.

METHODS

112 hospitalized patients with confirmed SARS-CoV-2 infection were retrospectively enrolled. CUS was performed within 2 days of admission and consisted in the assessment of the proximal and distal deep venous systems. Lack of compressibility, or direct identification of an endoluminal thrombus, were the criteria used for the diagnosis of DVT. Pulmonary embolism (PE) events were investigated at computed tomography pulmonary angiography (CTPA) within 5 days of follow-up. Logistic binary regression was computed to determine which clinical and radiological parameters were independently associated with PE onset.

RESULTS

Overall, the incidence of DVT in our cohort was about 43%. The most common district involved was the left lower limb (68.7%) in comparison with the right one (58.3%) while the upper limbs were less frequently involved (4.2% the right one and 2.1% the left one, respectively). On both sides, the distal tract of the popliteal vein was the most common involved (50% right side and 45.8% left side). The presence of DVT in the distal tract of the right popliteal vein (OR = 2.444 95%CIs 1.084-16.624, p = 0.038), in the distal tract of the left popliteal vein (OR = 4.201 95%CIs 1.484-11.885, p = 0.007), and D-dimer values (OR = 2.122 95%CIs 1.030-5.495, p = 0.003) were independently associated with the onset on PE within 5 days.

CONCLUSIONS

CUS should be considered a useful tool to discriminate which category of patients can develop PE within 5 days from admission.

Venous Thromboembolism in Sepsis: From Bench to Bedside

Septic patients were commonly affected by coagulation disorders; thus, they are at high risk of thrombotic complications. In the last decades, novel knowledge has emerged about the interconnected and reciprocal influence of immune and coagulation systems. This phenomenon is called immunothrombosis, and it indicates an effective response whereby immune cells and the coagulation cascade cooperate to limit pathogen invasion and endothelial damage. When this network becomes dysregulated due to a systemic inflammatory activation, as occurs during sepsis, it can result in pathological thrombosis. Endothelium, platelets and neutrophils are the main characters involved in this process, together with the TF and coagulation cascade, playing a critical role in both the host defense and in thrombogenesis. A deeper understanding of this relationship may allow us to answer the growing need for clinical instruments to establish the thrombotic risk and treatments that consider more the connection between coagulation and inflammation. Heparin remains the principal therapeutical response to this phenomenon, although not sufficiently effective. To date, no other significant alternatives have been found yet. In this review, we discuss the role of sepsis-related inflammation in the development and resolution of venous thromboembolism and its clinical implications, from bench to bedside.

Utility of Thromboelastography and velocity curve derivative in diagnosing COVID-19 associated coagulopathy

Background

COVID‐19 associated coagulopathy (CAC) can either be localized or systemic hypercoagulable state with increased risk of thromboembolism. This study looked into the usefulness of Thromboelastography (TEG) and the velocity curve (V‐curve) derivative from TEG in diagnosing and differentiating different stages of CAC.

Materials and Methods

A prospective single cohort study of RT‐PCR confirmed COVID‐19 patients was carried out for 2 weeks. Severe COVID‐19 patients in the adult critical care units with a TEG report were recruited for the study. Citrated kaolin TEG was performed on the day of admission before anticoagulation. TEG parameters included were R and K time, alpha angle, maximum amplitude, clotting index, lysis at 30 min. The first‐degree velocity curve of TEG is plotted as V‐curve which extrapolates thrombus generation potential. Parameters analyzed were the maximum rate of thrombus generation as well as thrombus generated (TG).

Results

The study included 43 patients with an average age of 58.34 (±15.35). TEG as well as V‐curve of all the patients were hypercoagulable compared with age‐matched reference range. We had 79.06% of patients in hypercoagulable stage. The mortality rate was 32.56% and 30.23% developed thrombotic incidents. Patients who succumbed to death had prolonged PT, aPTT, MA, Ly30, with a reduced TG (p < .05). The presence of fibrinolysis was associated with thromboembolism (OR = 6.76, CI = 1.48–25.82). Repeat TEG was done randomly in 11 patients and revealed a persistent hypercoagulable stage with increasing fibrinolysis activity.

Conclusion

TEG is a useful tool in diagnosing and categorizing Coagulopathy associated with COVID‐19.

Effects of low molecular weight heparin and fondaparinux on mortality, hemorrhagic and thrombotic complications in COVID-19 patients

Background:

Coronavirus disease 2019 (COVID-19) is associated with increased thrombosis prevalence. However, there are insufficient data supporting the appropriate anticoagulation dose in COVID-19.

Objective:

We aim to systematically assess the currently available data regarding the effects of different dosing regimens of low molecular weight heparin and/or fondaparinux (LMWH/F) on mortality risk as well as the risk of arterial/venous thrombotic events and hemorrhagic complications in confirmed COVID-19 cases.

Design:

We conducted a living systematic review and meta-analysis on the effects of different LMWH/F doses on mortality, thrombotic and hemorrhagic events in COVID-19 patients.

Data Sources and Methods:

MEDLINE, Scopus, Embase, Cochrane Library, Cochrane COVID-19 study register, European Union Drug Regulating Authorities Clinical Trials Database, and ClinicalTrials.gov were searched to detect observational cohort studies and randomized-controlled clinical trials (RCTs) comparing difference doses of LMWH/F among confirmed COVID-19 cases.

Results:

Thirty-one eligible studies (6 RCTs and 25 cohort studies) with 11,430 hospitalized patients were included. No association was found between LMWH/F and mortality during the following comparisons: (1) no LMWH/F versus any LMWH/F; (2) prophylactic versus higher than prophylactic LMWH/F; (3) prophylactic versus therapeutic LMWH/F; (4) intermediate versus therapeutic LMWH/F; and (5) lower than therapeutic versus therapeutic LMWH/F. Mortality was higher in patients receiving prophylactic versus intermediate LMWH/F (OR = 2.01; 95% CI: 1.19–3.39). However, this effect was mostly driven by observational data. No associations were detected between the intensity of LMWH/F and the risk of thrombotic and hemorrhagic events, except the lower risk for hemorrhage in patients on prophylactic compared to higher LMWH/F doses.

Conclusion:

The risk for all-cause mortality was higher in patients receiving prophylactic LMWH/F compared to those on an intermediate dose of LMWH/F, based on observational data. These results should be interpreted in light of the moderate quality and heterogeneity of the included studies.

Registration:

The study protocol has been registered in the International Prospective Register of Ongoing Systematic Reviews PROSPERO (Registration number: CRD42021229771).

Screening for asymptomatic deep vein thrombosis in COVID-19 patients admitted to the medical ward: a cross-sectional study

Purpose

Patients with COVID-19 have an increased risk for venous thrombo-embolism (VTE), especially pulmonary embolism. The exact prevalence of asymptomatic DVT is not known, as is the usefulness of screening for DVT in patients admitted to ward with COVID-19. We have studied the prevalence of asymptomatic DVT.

Methods

We performed a cross-sectional observational multi-center study at four university medical centers in The Netherlands. All adult patients admitted with COVID-19 to a medical ward were eligible for inclusion, including patients who were transferred back from the ICU to the ward. The study protocol consisted of weekly cross-sectional rounds of compression ultrasound.

Results

In total, 125 patients were included in the study. A significant proportion of patients (N = 34 (27%)) had developed a VTE during their admission for COVID-19 before the study ultrasound was performed. In most VTE cases (N = 27 (79%)) this concerned pulmonary embolism. A new asymptomatic DVT was found in 5 of 125 patients (4.0%; 95% CI 1.3–9.1%) (Table 2). Nine patients (7.2%; 95% CI 3.3–13.2%) developed a VTE (all PE) diagnosed within 28 days after the screening US was performed.

Conclusion

We have shown a low prevalence (4%) of newly discovered asymptomatic DVT outside the ICU-setting in COVID-19 patients. Despite this low prevalence, nine patients developed PE (7%) within 28 days after ultrasound. This favors the hypothesis of local thrombus formation in the lungs. Based on our findings and literature, we do not recommend US-screening of asymptomatic patients with COVID-19 admitted to the ward.

Multiorgan Involvement in SARS-CoV-2 Infection: The Role of the Radiologist from Head to Toe

Radiology plays a crucial role for the diagnosis and management of COVID-19 patients during the different stages of the disease, allowing for early detection of manifestations and complications of COVID-19 in the different organs. Lungs are the most common organs involved by SARS-CoV-2 and chest computed tomography (CT) represents a reliable imaging-based tool in acute, subacute, and chronic settings for diagnosis, prognosis, and management of lung disease and the evaluation of acute and chronic complications. Cardiac involvement can be evaluated by using cardiac computed tomography angiography (CCTA), considered as the best choice to solve the differential diagnosis between the most common cardiac conditions: acute coronary syndrome, myocarditis, and cardiac dysrhythmia. By using compressive ultrasound it's possible to study the peripheral arteries and veins and to exclude the deep vein thrombosis, directly linked to the onset of pulmonary embolism. Moreover, CT and especially MRI can help to evaluate the gastrointestinal involvement and assess hepatic function, pancreas involvement, and exclude causes of lymphocytopenia, thrombocytopenia, and leukopenia, typical of COVID-19 patients. Finally, radiology plays a crucial role in the early identification of renal damage in COVID-19 patients, by using both CT and US. This narrative review aims to provide a comprehensive radiological analysis of commonly involved organs in patients with COVID-19 disease.

Factors Associated with Positive Thrombus Findings at Ultrasonography in Covid-19 Ward Patients who Underwent Imaging for Suspected DVT Under Prophylactic Anticoagulation

OBJECTIVE

The incidence of deep vein thrombosis (DVT) is increased in Covid-19 patients and its presence is associated with worse outcomes. Ultrasound (USG) examination of Covid-19 patients suspected DVT is challenging due to concerns with disease transmission, while timely initiation of therapeutic anticoagulation is essential. This study aimed to identify patient factors associated with positive thrombus findings at ultrasonography in Covid-19 ward patients who underwent imaging for suspected DVT.

METHOD

Patients that did not require intensive care unit treatment, who underwent ultrasound imaging for suspected DVT between March - December 2020 were retrospectively included. Patient demographics, comorbidities, modified Well's score, and D-Dimer results on the day of ultrasound were recorded. Parameters for a higher likelihood of a positive DVT result were determined by comparing patients with confirmed DVT at USG and patients with negative USG findings. To determine a cut-off for D-Dimer levels a ROC curve was constructed. The sensitivity and specificity of the determined high-risk factors in the prediction of positive USG results were calculated.

RESULTS

A positive history for DVT (25% vs 4%, p<0.001), thrombophilia (9% vs 2%, p=0.048), immobilization (53% vs 23%, p=0.001), and a Well's score ≥ 2 (50% vs 21%, p=0.001) were more frequent in patients with DVT. Mean D-Dimer levels were higher in patients with DVT (3871 ± 1805 vs 2075 ± 1543, p<0.001). The presence of either thrombophilia or D-Dimer > 2020 had a sensitivity of 93% and a specificity of 64%. The presence of either thrombophilia, D-Dimer > 2020, or a Well's score ≥ 2 had a sensitivity of 100% and a specificity of 51%.

CONCLUSION

Covid-19 patients with D-Dimer > 2020, a positive history for thrombophilia, and a Well's score ≥ 2 should undergo a timely ultrasound examination. The high risk of DVT should be remembered for all hospitalized Covid-19 patients.

Coagulopathy and Brain Injury Pathogenesis in Post-Covid-19 Syndrome

The post-COVID neurological syndrome has been coined, which describes the functional and structural sequelae of coronavirus infection disease-19 (COVID-19) in the brain. Mild/severe manifestations of the post-COVID neurological syndrome have been identified in approximately 33.00% of COVID-19 survivors. The presence of neurological complications after COVID allowed neuropathologists to investigate in-depth the role of viral infection in neurons. The pathophysiology of the post-COVID neurological syndrome involved the development of a systematic response, including coagulopathy characterized by the formation of microthrombi. Coagulopathy, an old term for a new disease, describes the discrepancy between pro-coagulant and anticoagulant systems due to overexpression of pro-coagulant substances and or their receptors in addition to suppression of the anticoagulant molecules and or their receptors. Vascular endothelial cells and hepatocytes play a central role in the regulation of hemostasis that is disrupted during the acute phase response (APR) of coronavirus-19 (COVID-19). Currently, coagulopathy and inflammation are termed together since both form a complementary system, indicated by the elevation of inflammatory biomarkers (APR) and fibrinolysis biomarkers (D-dimer/fibrin). The later events of the post-COVID neurological syndrome are primarily induced by coagulopathy and direct viral tropism. Therefore, the paper introduces the hypothesis of coagulopathy induced post-COVID neurological syndrome.

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.

COVID and venous thrombosis: systematic review of literature

INTRODUCTION

We aimed to review the prevalence, the risk factors and the outcomes of venous thrombosis (VT) in patients hospitalized for COronaVirus Disease 19 (COVID-19).

METHODS

Electronic bibliographic databases were searched using the words "COVID venous thrombosis". The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement standards.

RESULTS

The search of the Literature retrieved 877 results. After assessment of full texts, 69 papers were included in the qualitative analysis and 23 of them in the quantitative evaluation. The analyzed studies included a total of 106838 patients hospitalized for COVID-19 from 01/2020 to 12/2020. The pooled reported prevalence rate of VT was in median 16.7% (IQR 5.8%-30%), being higher in ICU patients (60.8%-85.4%). VT events were reported in about 75% of cases in the popliteal and calf veins. Signs and symptoms were present in 6.1% of cases. At quantitative evaluation, older age, D-dimer and obesity increased the odds to experience a VT (OR 3.54, 95%CI 0.65-6.43, P=0.01; OR=956.86, 95%CI 225.67-1668.05, P=0.01; OR 1.42, 95%CI 1.01-1.99, P=0.03 respectively). Female sex seemed to be protective against the odds of VT (OR 0.77, 95%CI 0.63-0.93, P=0.007).

CONCLUSIONS

Among patients hospitalized for COVID-19, VT is a relatively common finding, with higher prevalence rates in ICU patients. VT occurs mostly in the distal regions of the lower limb and is asymptomatic in most cases. Older age, obesity and higher D-dimer values on admission increased the odds of VT, while female sex was protective against the odds of VT.