Fondaparinux Sodium: Recent Advances in the Management of Thrombosis.

Fondaparinux sodium is a chemically synthesized selective factor Xa inhibitor approved for the prevention and treatment of venous thromboembolic events, that is, deep vein thrombosis, pulmonary embolism, and superficial vein thrombosis, in acutely ill (including those affected by COVID-19 or cancer patients) and those undergoing surgeries. Since its approval in 2002, the efficacy and safety of fondaparinux is well demonstrated by many clinical studies, establishing the value of fondaparinux in clinical practice. Some of the advantages with fondaparinux are its chemical nature of synthesis, minimal risk of contamination, 100% absolute bioavailability subcutaneously, instant onset of action, a long half-life, direct renal excretion, fewer adverse reactions when compared with direct oral anticoagulants, and being an ideal alternative in conditions where oral anticoagulants are not approved for use or in patients intolerant to low molecular weight heparins (LMWH). In the last decade, the real-world use of fondaparinux has been explored in other conditions such as acute coronary syndromes, bariatric surgery, in patients developing vaccine-induced immune thrombotic thrombocytopenia (VITT) and in pregnant women with heparin-induced thrombocytopenia (HIT), or those intolerant to LMWH. The emerging data from these studies have culminated in recent updates in the guidelines that recommend the use of fondaparinux under various conditions. This paper aims to review the recent data and the subsequent updates in the recommendations of various guidelines on the use of fondaparinux sodium.

Efficacy and Safety of Direct Oral Anticoagulants Compared With Heparin for Preventing Thromboembolism in Hospitalized Patients With COVID-19: A Systematic Review and Meta-Analysis.

A high rate of thromboembolism and a high risk of death have been reported regarding hospitalized patients with coronavirus disease 2019 (COVID-19). Recently, we noticed that clinicians in some comparative studies used direct oral anticoagulants (DOACs) to prevent thromboembolism in patients with COVID-19. However, it is uncertain whether DOACs are better than recommended heparin for hospitalized patients with COVID-19. Therefore, a direct comparison of the prophylactic effects and safety between DOACs and heparin is needed. We systematically searched PubMed, Embase, Web of Science, and the Cochrane Library from 2019 to December 1, 2022. Randomized controlled trials or retrospective studies comparing the efficacy or safety of DOACs with that of heparin in preventing thromboembolism for hospitalized patients with COVID-19 were included. We assessed endpoints and publication bias using Stata 14.0. Five studies comprising 1360 hospitalized COVID-19 patients with mild to moderate cases were identified in the databases. Comparing the embolism incidence, we found that DOACs had a better effect than heparin, mainly low-molecular-weight heparin (LMWH), in preventing thromboembolism (risk ratio [RR] = 0.63, 95% confidence interval [CI] [0.43-0.91], P = 0.014). Considering safety, DOACs resulted in less bleeding than heparin during hospitalization (RR = 0.52, 95% CI [0.11-2.44], P = 0.411). Similar mortality was discovered in the 2 groups (RR = 0.94, 95% CI [0.59-1.51], P = 0.797). In noncritically hospitalized patients with COVID-19, DOACs are superior to heparin, even LMWH, in preventing thromboembolism. Compared with heparin, DOACs have a lower trend of bleeding and yield a similar mortality rate. Therefore, DOACs may be a better alternative for patients with mild to moderate COVID-19.

Bleeding and thrombosis outcomes in hospitalised COVID-19 patients on low-molecular-weight heparin and antiplatelet therapy.

BACKGROUND: An increased incidence of thromboembolic events in hospitalised COVID­19 patients has been demonstrated despite the use of low-molecular-weight heparin (LMWH). Antiplatelet therapy prior to admission and early in the disease course has been hypothesised to be protective against thrombosis. OBJECTIVES: To describe the bleeding and thrombosis outcomes in hospitalised patients with confirmed COVID­19 receiving LMWH, with and without concomitant antiplatelet therapy. Secondary objectives were to explore predictors of bleeding and thrombosis outcomes, and dosing practices of antiplatelet therapy and LMWH. METHODS: We conducted a descriptive, cross-sectional study of bleeding and thrombosis outcomes at Tygerberg Academic Hospital, Cape Town, South Africa, during the first COVID­19 wave, in 808 hospitalised patients with confirmed COVID­19 receiving LMWH with and without concomitant antiplatelet therapy. Multivariate logistic regression analysis was performed if predictors were deemed statistically and clinically significant. RESULTS: Patients receiving both LMWH and antiplatelet therapy had similar bleeding outcomes compared with patients only receiving LMWH (odds ratio (OR) 1.5; 95% confidence interval (CI) 0.6 - 4.0). Patients receiving both LMWH and antiplatelet therapy had increased odds of developing thrombosis compared with patients only receiving LMWH (OR 4.8; 95% CI 2.1 - 10.7). CONCLUSION: The bleeding risk in COVID­19 patients receiving both LMWH and antiplatelet therapy was not significantly increased. A potentially higher risk of thrombosis in patients receiving LMWH and antiplatelet therapy was observed. However, this could reflect confounding by indication. Randomised studies are required to further evaluate the use of antiplatelet therapy to treat hospitalised patients with COVID­19.

The pharmacology of anticoagulant drug treatment options in COVID-19 patients: reviewing real-world evidence in clinical practice.

INTRODUCTION: The optimal anticoagulation strategy for venous thromboembolism (VTE) prevention among COVID-19 patients, hospitalized or in the community setting, is still challenging and largely based on real-world evidence. AREAS COVERED: We analyzed real-world data regarding the safety and effectiveness of anticoagulant treatment, both parenteral and oral, for VTE prevention or atrial fibrillation (AF)/VTE treatment among COVID-19 patients. EXPERT OPINION: The efficacy of low-molecular-weight heparin (LMWH) doses for VTE prevention correlates with COVID-19 disease status. LMWH prophylactic dose may be useful in COVID-19 patients at the early stage of the disease. LMWH intermediate or therapeutic dose is recommended in COVID-19 patients with an advanced stage of the disease. COVID-19 patients on VKA therapy for atrial fibrillation (AF) and VTE should switch to NOACs in the community setting or LMWH in the hospital setting. No definitive data on de-novo starting of NOACs or VKA therapy for VTE prevention in COVID-19 outpatients are available. In patients at high risk discharged after hospitalization due to COVID-19, thromboprophylaxis with NOACs may be considered.

Anticoagulants for thrombosis prophylaxis in acutely ill patients admitted to hospital: systematic review and network meta-analysis.

OBJECTIVE: To assess the benefits and harms of different types and doses of anticoagulant drugs for the prevention of venous thromboembolism in patients who are acutely ill and admitted to hospital. DESIGN: Systematic review and network meta-analysis. DATA SOURCES: Cochrane CENTRAL, PubMed/Medline, Embase, Web of Science, clinical trial registries, and national health authority databases. The search was last updated on 16 November 2021. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Published and unpublished randomised controlled trials that evaluated low or intermediate dose low-molecular-weight heparin, low or intermediate dose unfractionated heparin, direct oral anticoagulants, pentasaccharides, placebo, or no intervention for the prevention of venous thromboembolism in acutely ill adult patients in hospital. MAIN OUTCOME MEASURES: Random effects, bayesian network meta-analyses used four co-primary outcomes: all cause mortality, symptomatic venous thromboembolism, major bleeding, and serious adverse events at or closest timing to 90 days. Risk of bias was also assessed using the Cochrane risk-of-bias 2.0 tool. The quality of evidence was graded using the Confidence in Network Meta-Analysis framework. RESULTS: 44 randomised controlled trials that randomly assigned 90 095 participants were included in the main analysis. Evidence of low to moderate quality suggested none of the interventions reduced all cause mortality compared with placebo. Pentasaccharides (odds ratio 0.32, 95% credible interval 0.08 to 1.07), intermediate dose low-molecular-weight heparin (0.66, 0.46 to 0.93), direct oral anticoagulants (0.68, 0.33 to 1.34), and intermediate dose unfractionated heparin (0.71, 0.43 to 1.19) were most likely to reduce symptomatic venous thromboembolism (very low to low quality evidence). Intermediate dose unfractionated heparin (2.63, 1.00 to 6.21) and direct oral anticoagulants (2.31, 0.82 to 6.47) were most likely to increase major bleeding (low to moderate quality evidence). No conclusive differences were noted between interventions regarding serious adverse events (very low to low quality evidence). When compared with no intervention instead of placebo, all active interventions did more favourably with regard to risk of venous thromboembolism and mortality, and less favourably with regard to risk of major bleeding. The results were robust in prespecified sensitivity and subgroup analyses. CONCLUSIONS: Low-molecular-weight heparin in an intermediate dose appears to confer the best balance of benefits and harms for prevention of venous thromboembolism. Unfractionated heparin, in particular the intermediate dose, and direct oral anticoagulants had the least favourable profile. A systematic discrepancy was noted in intervention effects that depended on whether placebo or no intervention was the reference treatment. Main limitations of this study include the quality of the evidence, which was generally low to moderate due to imprecision and within-study bias, and statistical inconsistency, which was addressed post hoc. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42020173088.

Low-molecular-weight heparin compared with unfractionated heparin in critically ill COVID-19 patients.

BACKGROUND: Thrombosis in COVID-19 worsens mortality. In our study, we sought to investigate how the dose and type of anticoagulation (AC) can influence patient outcomes. METHODS: This is a single-center retrospective analysis of critically ill intubated patients with COVID-19, comparing low-molecular-weight heparin (LMWH) and unfractionated heparin (UFH) at therapeutic and prophylactic doses. Of 218 patients, 135 received LMWH (70 prophylactic, 65 therapeutic) and 83 UFH (11 prophylactic, 72 therapeutic). The primary outcome was mortality. Secondary outcomes were thromboembolic complications confirmed on imaging and major bleeding complications. Cox proportional-hazards regression models were used to determine whether the type and dose of AC were independent predictors of survival. We performed Kaplan-Meier survival analysis to compare the cumulative survivals. RESULTS: Overall, therapeutic AC, with either LMWH (65% vs 79%, P = .09) or UFH (32% vs 46%, P = .73), conveyed no survival benefit over prophylactic AC. UFH was associated with a higher mortality rate than LMWH (66% vs 28%, P = .001), which was also evident in the multivariable analysis (LMWH vs UFH mortality, hazard ratio: 0.47, P = .001) and in the Kaplan-Meier survival analysis. Thrombotic and bleeding complications did not depend on the AC type (prophylactic LMWH vs UFH: thrombosis P = .49, bleeding P = .075; therapeutic LMWH vs UFH: thrombosis P = .5, bleeding P = .17). When comparing prophylactic with therapeutic AC, the rate of both thrombotic and bleeding complications was higher with the use of LMWH compared with UFH. In addition, transfusion requirements were significantly higher with both therapeutic LMWH and UFH. CONCLUSIONS: Among intubated critically ill COVID-19 intensive care unit patients, therapeutic AC, with either LMWH or UFH, conveyed no survival benefit over prophylactic AC. AC with LMWH was associated with higher cumulative survival compared with AC with UFH.

Retroperitoneal hematoma in COVID-19 patients - case series.

COVID-19 patients, particularly those with severe pulmonary involvement, are at an increased thromboembolic risk related, among various causes, to the cytokine storm and excessive activation of the coagulation cascade and platelets. Different intensity of anticoagulation for them is proposed, mainly with low molecular weight heparins (LMWHs); in a confirmed pulmonary embolism (PE) the therapeutic dose of LMWH is routinely used. Some authors suggest that hemorrhagic complications in COVID-19 patients are rare. At the same time, one can find reports on internal bleeding, including retroperitoneal hematoma (RPH) and other abdominal hematomas. CASE REPORTS: The authors describe 5 cases (3 of those aged more than 80 years) with giant RPHs and with moderate/severe COVID-19 pneumonia, treated before RPH diagnosis with different enoxaparin doses. The therapeutic dose was given to the male with verified PE limited to the segmental/subsegmental pulmonary arteries and initially to the female in whom echocardiography was strongly suggestive of PE, yet this diagnosis was excluded on CT angiography. In one patient, the enoxaparin dose was escalated from 40 mg bd to 60 mg bd after the D-dimer increase. Two patients had bleeding complications despite the enoxaparin dose restricted to 40 mg/daily or bd. Two males had a coexistent psoas hematoma while in only one female there was a coexistent femoral hematoma. RPHs occurred between day 4 and 14 of hospitalization and all were treated conservatively. Three patients who died were particularly charged, so their deaths were not merely directly associated with RPH, which was closely analyzed in one autopsy performed. The authors underline that the choice of anticoagulation intensity in patients with COVID-19 pneumonia without venous thromboembolism seems sometimes difficult but recent publications indicate the low prophylactic enoxaparin dose as an optimal option. Anticoagulation dose escalation based only on the D-dimer level may not be appropriate for certain patients; moreover, the D-dimer increase is commonly observed during internal bleeding.

Slow versus fast subcutaneous heparin injections for prevention of bruising and site pain intensity.

BACKGROUND: Heparin is an anticoagulant medication that is usually injected subcutaneously. Subcutaneous administration of heparin may result in complications such as bruising, haematoma, and pain at the injection site. One of the factors that may affect pain, haematoma, and bruising is injection speed. Several studies have been carried out to determine if speed of injection affects the amount of pain and bruising where the injection is given; however, the results of these studies have differed, and study authors have not reached a clear final conclusion. This is the second update of a review first published in 2014. OBJECTIVES: To assess the effects of duration (speed) of subcutaneous heparin injection on pain and bruising at the injection site in people admitted to hospitals or clinics who require treatment with unfractionated heparin (UFH) or low molecular weight heparin (LMWH). We also looked at haematoma at the injection site. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 22 June 2020. We undertook reference checking of included studies to identify additional studies. SELECTION CRITERIA: We searched for randomised controlled trials (RCTs) comparing the effects of different durations of subcutaneous injection of heparin on pain, bruising, and haematoma at the injection site. DATA COLLECTION AND ANALYSIS: For this update, two review authors independently selected studies and extracted data via Covidence software and assessed methodological quality using Cochrane's risk of bias tool. The primary outcomes of interest were pain intensity at injection site and size and incidence of bruising. The secondary outcomes of interest were size and incidence of haematoma at injection site. We calculated the odds ratio (OR), mean difference (MD), or standardised mean difference (SMD) with corresponding 95% confidence intervals (CIs). We assessed the certainty of the evidence using GRADE criteria. MAIN RESULTS: We identified one new study for this update, resulting in a total of five included studies with 503 participants who received subcutaneous injections of LMWH into the abdomen. Given the nature of the intervention, it was not possible to blind participants and caregivers (personnel) in any of the included studies. Two studies described blinding of outcome assessors. Overall, the methodological quality of included studies was moderate. The duration of the fast injection was 10 seconds, and the duration of the slow injection was 30 seconds in all included studies. Four studies reported site pain intensity after each injection at different time points. Two studies assessed site pain intensity immediately after each injection; meta-analysis showed no evidence of a difference in site pain intensity immediately after slow injection when compared to fast injection (MD -1.52, 95% CI -3.56 to 0.53; 140 participants; low-certainty evidence). Meta-analysis of three studies indicated that site pain intensity may be slightly reduced 48 hours after the slow heparin injection compared to fast injection (MD -1.60, 95% CI -2.69 to -0.51; 103 participants; low-certainty evidence). Five studies assessed bruise size at 48 hours, and two studies assessed bruise size at 60 hours. Meta-analysis showed there may be a reduction in bruise size 48 hours (SMD -0.54, 95% CI -1.05 to -0.02; 503 participants; 5 studies; very low-certainty evidence) and 60 hours (SMD -0.49, 95% CI -0.93 to -0.06; 84 participants; 2 studies; low-certainty evidence) after slow injection compared to fast injection. There was no evidence of a difference in bruise size 72 hours after slow injection compared to fast injection (SMD -0.27, 95% CI -0.61 to 0.06; 140 participants; 2 studies; low-certainty evidence). Three studies evaluated incidence of bruising and showed there may be a reduction in bruise incidence 48 hours (OR 0.39, 95% CI 0.26 to 0.60; 444 participants; low-certainty evidence) and 60 hours (OR 0.25, 95% CI 0.10 to 0.65; 84 participants; 2 studies; low-certainty evidence) after slow injection compared to fast injection. We downgraded the certainty of the evidence due to risk of bias concerns, imprecision, and inconsistency. None of the included studies measured size or incidence of haematoma. AUTHORS' CONCLUSIONS: Administering medication safely and enhancing patient comfort are the main aims of clinical nurses. In this review, we identified five RCTs that evaluated the effect of subcutaneous heparin injection duration on pain intensity, bruise size and incidence. We found that pain may be slightly reduced 48 hours after slow injection. Similarly, there may be a reduction in bruise size and incidence after slow injection compared to fast injection 48 and 60 hours postinjection. We downgraded the certainty of the evidence for all outcomes to low or very low due to risk of bias concerns, imprecision, and inconsistency. Accordingly, new trials with a more robust design, more participants, and a focus on different injection speeds will be useful in strengthening the certainty of the available evidence.

Anticoagulation for COVID-19 Patients: A Bird's-Eye View.

Coronavirus disease 2019 (COVID-19) is a systemic disease that can be life-threatening involving immune and inflammatory responses, and that can result in potentially lethal complications, including venous thrombo-embolism (VTE). Forming an integrative approach to thrombo-prophylaxis and coagulation treatment for COVID-19 patients ensues. We aim at reviewing the literature for anticoagulation in the setting of COVID-19 infection to provide a summary on anticoagulation for this patient population. COVID-19 infection is associated with a state of continuous inflammation, which results in macrophage activation syndrome and an increased rate of thrombosis. Risk assessment models to predict the risk of thrombosis in critically ill patients have not yet been validated. Currently published guidelines suggest the use of prophylactic intensity over intermediate intensity or therapeutic intensity anticoagulant for patients with critical illness or acute illness related to COVID-19 infection. Critically ill COVID-19 patients who are diagnosed with acute VTE are considered to have a provoking factor, and, therefore, treatment duration should be at least 3 months. Patients with proximal deep venous thrombosis or pulmonary embolism should receive parenteral over oral anticoagulants with low-molecular-weight heparin or fondaparinux preferred over unfractionated heparin. In patients with impending hemodynamic compromise due to PE, and who are not at increased risk for bleeding, reperfusion may be necessary. Internists should remain updated on new emerging evidence regarding anticoagulation for COVID-19 patients. Awaiting these findings, we invite internists to perform individualized decisions that are unique for every patient and to base them on clinical judgment for risk assessment.

Use of low-molecular weight heparin, transfusion and mortality in COVID-19 patients not requiring ventilation.

It is still debated whether prophylactic doses of low-molecular- weight heparin (LMWH) are always effective in preventing Venous Thromboembolism (VTE) and mortality in COVID-19. Furthermore, there is paucity of data for those patients not requiring ventilation. We explored mortality and the safety/efficacy profile of LMWH in a cohort of Italian patients with COVID-19 who did not undergo ventilation. From the initial cohort of 422 patients, 264 were enrolled. Most (n = 156, 87.7%) received standard LMWH prophylaxis during hospitalization, with no significant difference between medical wards and Intensive Care Unit (ICU). Major or not major but clinically relevant hemorrhages were recorded in 13 (4.9%) patients: twelve in those taking prophylactic LMWH and one in a patient taking oral anticoagulants (p: n.s.). Thirty-nine patients (14.8%) with median age 75 years. were transfused. Hemoglobin (Hb) at admission was significantly lower in transfused patients and Hb at admission inversely correlated with the number of red blood cells units transfused (p < 0.001). In-hospital mortality occurred in 76 (28.8%) patients, 46 (24.3%) of whom admitted to medical wards. Furthermore, Hb levels at admittance were significantly lower in fatalities (g/dl 12.3; IQR 2.4 vs. 13.3; IQR 2.8; Mann-Whitney U-test; p = 0.001). After the exclusion of patients treated by LMWH intermediate or therapeutic doses (n = 32), the logistic regression showed that prophylaxis significantly and independently reduced mortality (OR 0.31, 95% CI 0.13-0.85). Present data show that COVID-19 patients who do not require ventilation benefit from prophylactic doses of LMWH.

[Learning with COVID-19: what about anticoagulation?]

Infection caused by SARS-CoV-2 (COVID-19) is associated with an increased risk of thromboembolic disease. So-me authors recommend anticoagulation at therapeutic doses for, at least, the most severely ill patients; this practice is not free of risks, which is why only thromboembolic prophylaxis is recommended by other consensuses. In the case of previously anticoagulated patients, changing the oral anticoagulant for a low molecular weight heparin (LMWH) is generally recommended. We present the cases of two patients admitted due to COVID-19, without serious clinical data, in whom anticoagulation (acenocoumarol and rivaroxaban, respectively) was replaced by LMWH at therapeutic doses, both presenting abdominal bleeding. This type of bleeding is an infrequent complication in anticoagulated patients, but the concurrence of two cases in a short period of time in the context of the COVID-19 pandemic leads us to consider that there is not yet any clear evidence on therapeutic anticoagulation in SARS-CoV-2 infection.

The Association of Low Molecular Weight Heparin Use and In-hospital Mortality Among Patients Hospitalized with COVID-19.

PURPOSE: To determine the association between low molecular weight heparin (LMWH) use and mortality in hospitalized COVID-19 patients. METHODS: We conducted a retrospective study of patients consecutively enrolled from two major academic hospitals exclusively for COVID-19 in Wuhan, China, from January 26, 2020, to March 26, 2020. The primary outcome was adjusted in-hospital mortality in the LMWH group compared with the non-LMWH group using the propensity score. RESULTS: Overall, 525 patients with COVID-19 enrolled with a median age of 64 years (IQR 19), and 49.33% men. Among these, 120 (22.86%) were treated with LMWH. Compared with the non-LMWH group, the LMWH group was more likely to be older and male; had a history of hypertension, diabetes, coronary heart disease (CHD), or stroke; and had more severe COVID-19 parameters such as higher inflammatory cytokines or D-dimer. Compared with non-LMWH group, LMWH group had a higher unadjusted in-hospital mortality rate (21.70% vs. 11.10%; p = 0.004), but a lower adjusted mortality risk (adjusted odds ratio [OR], 0.20; 95% CI, 0.09-0.46). A propensity score-weighting analysis demonstrated similar findings (adjusted OR, 0.18; 95% CI, 0.10-0.30). Subgroup analysis showed a significant survival benefit among those who were severely (adjusted OR, 0.07; 95% CI, 0.02-0.23) and critically ill (adjusted OR, 0.32; 95% CI, 0.15-0.65), as well as among the elderly patients' age > 65, IL-6 > 10 times upper limit level, and D-dimer > 5 times upper limit level. CONCLUSIONS: Among hospitalized COVID-19 patients, LMWH use was associated with lower all-cause in-hospital mortality than non-LMWH users. The survival benefit was particularly significant among more severely ill patients.

Severe Bleeding Complications Resulting in Death Following Anticoagulant Treatment in COVID-19 Surgical Patients.

Microthrombi formation in the pulmonary circulation is one of the main pathophysiological mechanisms responsible for the unfavorable respiratory evolution of CoViD-19 patients. Low molecular weight heparin (LMWH) anticoagulant therapy is a major pillar of treatment. But sometimes LMWH causes severe complications that can result in death. This is a retrospective, descriptive study, covering September 2020 and presenting 3 cases of severe hemorrhages followed by death in COVID-19 anticoagulated patients in therapeutic doses with LMWH in the hospital units of origin. Patients had hematomas of the rectus abdominal muscles and hemoperitoneum (2 cases) respectively hematoma of left gluteal muscles (1 case). The 2 patients with hematoma of rectus abdominal muscles were operated. The death occurred between 1-4 days after hospitalization.

Therapeutic dosing of low-molecular-weight heparin may decrease mortality in patients with severe COVID-19 infection.

BACKGROUND: Venous thromboembolism or extensive thrombosis is relatively common in patients with severe COVID-19 infection and has been associated with increased mortality. During the current COVID-19 pandemic, several prophylactic doses and types of low-molecular-weight heparin (LMWH) are being used worldwide; however, there are no high-quality studies or recommendations for an optimal prophylactic LMWH dose. OBJECTIVES: Investigate the relationship between coagulation parameters and the LMWH dose, and mortality and ICU admission in hospitalized patients with severe COVID-19 pneumonia. DESIGN: Retrospective. SETTING: Tertiary care hospital. PATIENTS AND METHODS: Data on clinical features, coagulation parameters and anticoagulant medications of inpatients with severe COVID-19 were collected for the period between 11 March 2020 and 31 April 2020. MAIN OUTCOME MEASURES: Mortality and ICU admission for prophylactic dose LMWH (0.5 mg/kg twice daily) and therapeutic dose LMWH (1 mg/kg twice daily). SAMPLE SIZE: 154 cases. RESULTS: Ninety-eight (63.6%) patients were treated with the LMWH prophylactic dose and 56 (36.4%) patients were treated with the therapeutic dose. Forty-four (44.9%) of 98 patients using the prophylactic dose LMWH died, while 10 (17.9%) of 56 patients using the therapeutic dose LMWH died (P=.001). Mortality was 6.4-fold higher in the prophylactic dose LMWH users than in the therapeutic dose LMWH users (OR=6.5, 95% CI: 2.4-17.6, P<.001). CONCLUSIONS: Therapeutic dosing of LMWH may decrease mortality in patients with severe COVID-19 infected pneumonia. More aggressive thromboprophylaxis regimens using higher doses of heparin should be evaluated in prospective studies. LIMITATIONS: Lack of information about bleeding complications. LMWH was not compared with other anticoagulant therapies. There was no comparison between our two groups on the APACHE score. Used different doses of LMWH in different clinics in our hospital. Single-center, retrospective study. CONFLICT OF INTEREST: None.

Venous thromboembolism and bleeding in critically ill COVID-19 patients treated with higher than standard low molecular weight heparin doses and aspirin: A call to action.

BACKGROUND: Critically ill COVID-19 patients have a clear pattern of inflammation and hypercoagulable state. The main aim of the study was to evaluate the outcome of severe COVID-19 patients basing on prothrombotic risk factors (i.e. D-dimer). We also evaluated the impact of different doses of low molecular weight heparin (LMWH) on the incidence of bleedings. METHODS: The data of forty-two patients admitted to the Intensive Care Unit (ICU) were retrospectively analyzed. On ICU admission, patients with D-dimer < 3000 ng/mL (Group 1) received enoxaparin 4000 UI (6000 UI, if body mass index >35) subcutaneously b.i.d. and patients with D-dimer ≥ 3000 ng/mL (Group 2) received enoxaparin 100 UI/kg every 12 h. Aspirin was administered to all patients once a day. RESULTS: Both groups presented a high incidence of perivascular thrombosis (40.9% in Group 1 and 30% in Group 2). Patients of Group 2 suffered a higher incidence of venous thromboembolism (VTE) than Group 1 (65% vs 13.6%, p = 0.001). One patient (4.5%) of Group 1 and three patients (15%) of Group 2 suffered from minor bleeding; no patient had major bleeding. Group 2 had a longer ICU and hospital stay than Group 1 (11.5 ±â€¯5.6 vs 9.0 ±â€¯4.8 and 30 ±â€¯4.9 vs 21 ±â€¯2.3, p < 0.05, respectively) as well as increased ICU mortality (25% vs 9.1%). CONCLUSIONS: More severe critically ill COVID-19 patients have a high incidence of VTE and worse outcome, despite the use of heparin at the therapeutic dose. However, the use of heparin did not increase the incidence of bleeding complications.

Applicability of bedside ultrasonography for the diagnosis of deep venous thrombosis in patients with COVID-19 and treatment with low molecular weight heparin.

PURPOSE: The aim of this study was to evaluate the applicability of bedside ultrasonography for the diagnosis of deep venous thrombosis (DVT) in patients infected with corona virus disease 2019 (COVID-19) with and without treatment with low molecular weight heparin (LMWH). METHODS: We retrospectively analyzed the records of deceased and surviving patients in whom ultrasonography detected or not a DVT, and in whom LMWH was or not prescribed. RESULTS: The incidence of DVT is higher in the deceased (33/35) than in the surviving (22/46) patients. LMWH was administered in a larger proportion of surviving (18/22) than of deceased (18/33) patients. D-dimer concentrations decreased in patients who received LMWH in both groups. CONCLUSIONS: There was a high incidence of DVT in patients who succumbed to COVID-19. Bedside ultrasonography can detect the presence of DVT as early as possible and help assessing the risk of venous thromboembolism, allowing early and reasonable use of LMWH.