High-Dose Prophylactic Anticoagulation for COVID-19 Pneumonia: A Review of Benefits and Risks

The COVID-19 pandemic has had a devastating impact on a global scale, causing significant morbidity and mortality. The virus affects multiple organ systems, including the respiratory, cardiovascular, and coagulation systems, leading to severe pneumonia in some patients. Moreover, COVID-19 patients with severe pneumonia have a high incidence of thrombotic events, which can result in significant morbidity and mortality. Given the potential benefits of anticoagulation therapy in COVID-19 patients with thrombotic complications, recent studies have proposed high-dose prophylactic anticoagulation (HD-PA) therapy as a potential treatment option. In fact, some studies have suggested that HD-PA therapy may be more effective in reducing thrombotic events and mortality rates than other treatment options. This review aims to provide a comprehensive overview of the benefits and risks of HD-PA therapy for COVID-19 pneumonia patients. By synthesizing and analyzing the latest available research, we highlight patient selection criteria and discuss the optimal dosage, duration, and timing of therapy. Additionally, we review the potential risks associated with HD-PA therapy and provide recommendations for clinical practice. Ultimately, this review provides valuable insights into the use of HD-PA therapy in COVID-19 pneumonia patients and paves the way for further research in this critical area. By exploring the benefits and risks of this treatment option, we hope to provide healthcare professionals with the information they need to make informed decisions about the best course of treatment for their patients.

Safety and efficacy of prophylactic anticoagulation versus therapeutic anticoagulation in hospital-admitted COVID-19 patients: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

COVID-19 disease-related coagulopathy and thromboembolic complication, an important aspect of the disease pathophysiology, are frequent and associated with poor outcomes, particularly significant in hospitalized patients. Undoubtedly, anticoagulation forms a cornerstone for the management of hospitalized COVID-19 patients, but the appropriate dosing has been inconclusive and a subject of research. We aim to review existing literature and compare safety and efficacy outcomes of prophylactic and therapeutic dose anticoagulation in such patients.

METHODS

We did a systematic review and meta-analysis to compare the efficacy and safety of prophylactic dose anticoagulation when compared with therapeutic dosing in hospitalized COVID-19 patients. We searched PubMed, Google Scholar, EMBASE and COCHRANE databases from 2019 to 2021, without any restriction by language. We screened records, extracted data and assessed the risk of bias in the studies. RCTs that directly compare therapeutic and prophylactic anticoagulants dosing and are not placebo-controlled trials were included. Analyses of data were conducted using the Mantel-Haenszel random-effects model (DerSimonian-Laird analysis). The study is registered with PROSPERO (CRD42021265948).

RESULTS

We included three studies in the final quantitative analysis. The incidence of thromboembolic events in therapeutic anticoagulation was lower in comparison with prophylactic anticoagulation in hospitalized COVID-19 patients and reached statistical significance [RR 1·45, 95% CI (1.07, 1.97) I² -0%], whereas major bleeding as an adverse event was found lower in prophylactic anticoagulation in comparison with therapeutic anticoagulation that was statistically significant [RR 0·42, 95% CI(0.19, 0.93) I² -0%].

CONCLUSION

Our study shows that therapeutic dose anticoagulation is more effective in preventing thromboembolic events than prophylactic dose but significantly increases the risk of major bleeding as an adverse event. So, the risk-benefit ratio must be considered while using either of them.

低分子肝素联合阿司匹林预防脾破裂并下肢骨折患者围术期静脉血栓形成

OBJECTIVE

To investigate the effectiveness and safety of low molecular weight heparin combined with aspirin for perioperative prophylactic anticoagulation in patients with lower extremity fracture after splenectomy.

METHODS

The clinical data of 50 patients with splenic rupture combined with lower extremity fracture between January 2009 and June 2022 were retrospectively analyzed. All patients were given enoxaparin sodium at 48 hours after splenectomy, and stopped at 24 hours before fracture surgery. After fracture surgery, the patients were divided into aspirin group (group A, 15 cases), low molecular weight heparin group (group B, 16 cases), and low molecular weight heparin combined with aspirin group (group C, 19 cases) according to different anticoagulation regimens. The treatment course was 28 days. There was no significant difference in gender, age, body mass index, cause of injury, fracture site, time from injury to operation, complications, and other general data between groups ( P>0.05). The occurrence of venous thromboembolism (VTE) was observed; hemoglobin (Hb), platelet (PLT), D-D dimer, and fibrinogen degradation product (FDP) were recorded before operation and at 1, 3, and 7 days after operation, and the effect of anticoagulation regimen on coagulation function was observed. The incidences of wound complications and bleeding related complications were recorded, and the total perioperative blood loss, hidden blood loss, and overt blood loss were calculated.

RESULTS

The incidences of VTE in groups A, B, and C were 13.33% (2/15), 12.50% (2/16), and 5.26% (1/19), respectively, and there was no significant difference between groups ( χ ²=0.770, P=0.680). There was no portal vein thrombosis and no VTE-related death in the 3 groups. There was no significant difference in the levels of Hb, PLT, D-D dimer, and FDP between groups before and after operation ( P>0.05); and there was no significant difference in total perioperative blood loss, hidden blood loss, and overt blood loss between groups ( P>0.05). No local skin necrosis was found in all patients. In group A, 1 case occurred redness and swelling of incision; in group B, 1 case had incision discharge, redness, and swelling, and 1 case had fat liquefaction; in group C, 1 case had repeated incision exudation accompanied by local tissue redness and swelling, and 1 case had local hematoma. The incidences of adverse incision in groups A, B, and C were 6.66% (1/15), 12.50% (2/16), and 11.76% (2/19), respectively, with no significant difference ( χ ²=0.302, P=0.860). There were 4 cases of bleeding related complications, including 1 case of incision ecchymosis in groups A and B respectively, with the incidence of 6.66% and 6.25%, respectively; there was 1 case of incision hematoma and 1 case of bleeding in group C, with the incidence of 11.76%; showing no significant difference in the incidence of bleeding related complications between groups ( χ ²=0.268, P=0.875).

CONCLUSION

Perioperative combined use of low molecular weight heparin and aspirin for prevention of anticoagulation in patients with splenic rupture and lower extremity fracture can effectively prevent the occurrence of VTE without increasing the incidence of complications, which is an effective and safe treatment method. However, whether the incidence of VTE can be reduced needs to be further studied by expanding the sample size.

Coagulation Abnormalities and Management in Hospitalized Pediatric Patients With COVID-19

BACKGROUND

The incidence and severity of coagulation abnormalities have not been extensively studied in pediatric populations with coronavirus disease 2019 (COVID-19). Moreover, their association with an increased risk for thromboembolic events remains unclear, and there is a lack of evidence for optimal prophylactic antithrombotic management. The aim of our study was to present our experience in evaluation, management, and long-term outcomes of coagulation abnormalities in pediatric hospitalized patients with COVID-19.

METHODS

A prospective study was performed in all children hospitalized for COVID-19 during a 6-month period focusing on patients' coagulation abnormalities, the normalization of the coagulation profile with or without anticoagulation prophylaxis and the clinical outcome of the disease.

RESULTS

Two hundred twenty-three patients (median age: 11.4 months) were enrolled in the study. Coagulation abnormalities were detected in 92.4% of patients with increased D-dimer levels to be the most common abnormality detected in 84.3% of patients. Prophylactic anticoagulation was initiated only in 7 (3.1%) selected patients with severe COVID-19 and at least 2 risk factors for venous thromboembolism (VTE) and in all patients with previous history of VTE. Follow-up coagulation profile in 85 patients showed that changes over time had a tendency towards normalization irrespectively of the initiation of anticoagulant thromboprophylaxis. No thrombotic complications were observed 3 months upon discharge.

CONCLUSIONS

Although abnormal findings in coagulation profile were very common, they were not associated with risk for VTE even in severe cases. A trend of normalization early in the course of the disease was observed regardless of the use of anticoagulant thromboprophylaxis.

Prophylactic Rivaroxaban Therapy for Left Ventricular Thrombus After Anterior ST-Segment Elevation Myocardial Infarction

OBJECTIVES

The aim of this study was to investigate the effects of rivaroxaban on left ventricle thromboprophylaxis in patients with anterior ST-segment elevation myocardial infarction (STEMI).

BACKGROUND

Anterior STEMI is associated with an increased risk of left ventricular thrombus (LVT) formation. The contemporary role of prophylactic rivaroxaban therapy remains unclear.

METHODS

We randomly assigned 279 patients with anterior STEMI who had undergone primary percutaneous coronary intervention to receive, in a 1:1 ratio, low-dose rivaroxaban (2.5 mg twice daily for 30 days) and dual antiplatelet therapy (DAPT) or only DAPT. The primary efficacy outcome was the LVT formation within 30 days. Net clinical adverse events were assessed at 30 days and 180 days, including all-cause mortality, LVT, systemic embolism, rehospitalization for cardiovascular events, and bleeding.

RESULTS

The addition of low-dose rivaroxaban to DAPT reduced LVT formation within 30 days compared with only DAPT (0.7% vs 8.6%; HR: 0.08; 95% CI: 0.01-0.62; P = 0.015; P < 0.001 for superiority). Net clinical adverse events were lower within 30 days in the rivaroxaban group versus those in the only DAPT group and remained relatively low throughout the follow-up period. There were no significant differences in bleeding events between the 2 groups in 30 days and 180 days. However, 1 case of intracranial hemorrhage (major bleeding) occurred in the rivaroxaban group within 30 days.

CONCLUSIONS

Our results supported that the short-duration addition of low-dose rivaroxaban to DAPT could prevent LVT formation in patients with anterior STEMI following primary percutaneous coronary intervention. A larger multiple-institution study is necessary to determine the generalizability.

Asymptomatic Venous Thromboembolism After Hepatobiliary-Pancreatic Surgery: Early Detection Using D-dimer and Soluble Fibrin Monomer Complex Levels

AIM

The aim was to investigate the usefulness of a preemptive management strategy that includes monitoring serum D-dimer (DD) and soluble fibrin monomer complex (SFMC) levels for early detection and treatment of venous thromboembolism (VTE) after hepatobiliary-pancreatic (HBP) surgery.

METHODS

Overall, 678 patients who underwent HBP surgery between January 2010 and March 2020 were enrolled. Patients with increased postoperative serum DD or SFMC levels underwent contrast-enhanced computed tomography, and those with VTE received anticoagulant agents. The VTE risk factors were investigated using multivariable analysis. Postoperative changes in DD and SFMC levels were verified, and their ability to identify VTE was evaluated using receiver operating characteristic (ROC) analysis.

RESULTS

VTE developed in 83 patients (12.2%), and no symptomatic VTE or death due to VTE was observed. Multivariable analysis identified female sex (odds ratio [OR] 2.26; 95% confidence interval [CI] 1.41-3.60; P < .001) and surgery duration of ≥401 min (OR 2.07; 95% CI 1.27-3.35; P < .001) as independent risk factors for VTE. Maximum serum DD and SFMC levels in patients who developed VTE were significantly higher than those in patients without VTE (DD, 15.1 vs 8.9 μg/mL, P < .001; SFMC, 18.0 vs 10.2 μg/mL, P < .001, respectively). Both DD (n = 678) and the combination of DD and SFMC levels (n = 230) showed a good ability to detect VTE (area under the ROC curve, 0.804 and 0.761, respectively).

CONCLUSION

Our preemptive strategy of monitoring serum DD and SFMC levels enables early detection and treatment intervention of VTE after HBP surgery.

Primary Thromboprophylaxis in Patients with Malignancies: Daily Practice Recommendations by the Hemostasis Working Party of the German Society of Hematology and Medical Oncology (DGHO), the Society of Thrombosis and Hemostasis Research (GTH), and the Austrian Society of Hematology and Oncology (ÖGHO)

Patients with cancer, both hematologic and solid malignancies, are at increased risk for thrombosis and thromboembolism. In addition to general risk factors such as immobility and major surgery, shared by non-cancer patients, cancer patients are exposed to specific thrombotic risk factors. These include, among other factors, cancer-induced hypercoagulation, and chemotherapy-mediated endothelial dysfunction as well as tumor-cell-derived microparticles. After an episode of thrombosis in a cancer patient, secondary thromboprophylaxis to prevent recurrent thromboembolism has long been established and is typically continued as long as the cancer is active or actively treated. On the other hand, primary prophylaxis, even though firmly established in hospitalized cancer patients, has only recently been studied in ambulatory patients. This recent change is mostly due to the emergence of direct oral anticoagulants (DOACs). DOACs have a shorter half-life than vitamin K antagonists (VKA), and they overcome the need for parenteral application, the latter of which is associated with low-molecular-weight heparins (LMWH) and can be difficult for the patient to endure in the long term. Here, first, we discuss the clinical trials of primary thromboprophylaxis in the population of cancer patients in general, including the use of VKA, LMWH, and DOACs, and the potential drug interactions with pre-existing medications that need to be taken into account. Second, we focus on special situations in cancer patients where primary prophylactic anticoagulation should be considered, including myeloma, major surgery, indwelling catheters, or immobilization, concomitant diseases such as renal insufficiency, liver disease, or thrombophilia, as well as situations with a high bleeding risk, particularly thrombocytopenia, and specific drugs that may require primary thromboprophylaxis. We provide a novel algorithm intended to aid specialists but also family practitioners and nurses who care for cancer patients in the decision process of primary thromboprophylaxis in the individual patient.

Central pulmonary embolism in patients with Covid-19

BACKGROUND

The purpose was to evaluate central pulmonary embolism (PE) in patients with Covid-19. The association with severe radiological pulmonary changes, prophylactic anticoagulation and ICU care was assessed.

METHODS

From 1 March until 31 May 2020, all in-hospital patients with a positive PCR for SARS-CoV-2-RNA and PE diagnosed with computed tomography pulmonary angiography were identified through diagnostic codes in medical charts. PE was characterised as central/peripheral and unilateral/bilateral. Covid-19 related lung changes were evaluated scoring the proportion of affected lung (max-score score 25) for all five lobes in both lungs. ICU and non-ICU patients were included and anticoagulant regimens were assessed.

RESULTS

Of 1162 patients with Covid-19, 41 were diagnosed with PE (cumulative incidence 3.5%), and of these 63.4% (=overall 2.2%) had central PE. PE on admission was present in 46.3%. No differences were seen in the distribution of central vs. peripheral PE in relation to prophylactic anticoagulation (p=.317). Of ICU patients 82.4% were diagnosed with central PE compared to 50.0% among non-ICU patients (p=.05). No association was observed between the presence of central PE and the extent of radiological Covid-19 changes (p=.451). Mild (0-12 p) and severe (13-25 p) pulmonary changes were seen in 63.4% and 36.6% of patients respectively.

CONCLUSIONS

Overall, and especially in ICU-patients, a high proportion of central PE was seen and many were diagnosed at admission. No association between central PE and prophylactic anticoagulation, or the extent of pulmonary Covid-19 changes was observed.

Prophylactic anticoagulation for preterm premature rupture of membranes: a decision analysis

BACKGROUND

The current standard of care in the setting of preterm premature rupture of membranes involves antenatal hospitalization until delivery. The reduced physical activity during this time compounds the heightened risk for venous thromboembolism in pregnancy. Prophylactic anticoagulation can decrease this risk of venous thromboembolism; however, this benefit must be balanced against the risks of precluding neuraxial analgesia or increasing the risk of postpartum hemorrhage.

OBJECTIVE

The objective of this study was to determine the optimal modality for venous thromboembolism prophylaxis during hospitalization for preterm premature rupture of membranes using a decision analysis model.

STUDY DESIGN

A decision-analytical Markov model was constructed using the TreeAge software comparing the use of unfractionated heparin, low-molecular-weight heparin or no anticoagulation in women with a singleton pregnancy who were hospitalized for preterm premature rupture of membranes after 24 weeks and remained hospitalized until delivery. Maternal outcomes examined included attainment of neuraxial analgesia (vs no analgesia for vaginal delivery or general anesthesia for cesarean delivery), venous thromboembolism, postpartum hemorrhage, and maternal death. Probabilities and utilities were derived from existing literature. Sensitivity analyses were performed to interrogate model assumptions, and a Monte Carlo probabilistic sensitivity analysis was performed to examine the robustness of the model.

RESULTS

In this decision-analytical model, no prophylactic anticoagulation maximized maternal utilities. Clinical outcomes among a theoretical cohort of 100,000 women are shown in the Table. The 1- and 2-way sensitivity analyses supported this conclusion. Monte Carlo probabilistic sensitivity analysis indicated that no prophylaxis was the preferred choice in 56% of simulations, unfractionated heparin in 34% of simulations, and low-molecular-weight heparin in 10% of simulations.

CONCLUSION

Our results do not support the routine use of prophylactic anticoagulation in women admitted to the hospital for preterm premature rupture of membranes. These findings can be used to inform clinical decisions when admitting low-risk singleton pregnancies to the hospital in the setting of preterm premature rupture of membranes.

A Prospective Pilot Trial to Assess the Efficacy of Argatroban (Argatra®) in Critically Ill Patients with Heparin Resistance

The current study aims to evaluate whether prophylactic anticoagulation using argatroban or an increased dose of unfractionated heparin (UFH) is effective in achieving the targeted activated partial thromboplastin time (aPTT) of more than 45 s in critically ill heparin-resistant (HR) patients. Patients were randomized either to continue receiving an increased dose of UFH, or to be treated with argatroban. The endpoints were defined as achieving an aPTT target of more than 45 s at 7 h and 24 h. This clinical trial was registered on clinicaltrials.gov (NCT01734252) and on EudraCT (2012-000487-23). A total of 42 patients, 20 patients in the heparin and 22 in the argatroban group, were included. Of the patients with continued heparin treatment 55% achieved the target aPTT at 7 h, while only 40% of this group maintained the target aPTT after 24 h. Of the argatroban group 59% reached the target aPTT at 7 h, while at 24 h 86% of these patients maintained the targeted aPTT. Treatment success at 7 h did not differ between the groups (p = 0.1000), whereas at 24 h argatroban showed significantly greater efficacy (p = 0.0021) than did heparin. Argatroban also worked better in maintaining adequate anticoagulation in the further course of the study. There was no significant difference in the occurrence of bleeding or thromboembolic complications between the treatment groups. In the case of heparin-resistant critically ill patients, argatroban showed greater efficacy than did an increased dose of heparin in achieving adequate anticoagulation at 24 h and in maintaining the targeted aPTT goal throughout the treatment phase.

Do we need prophylactic anticoagulation in ambulatory patients with lung cancer? A review

Venous thromboembolism is a common complication of malignancy. Lung cancer is considered one of the most thrombogenic cancer types. Primary thromboprophylaxis is not currently recommended for all ambulatory patients with active cancer. In the present narrative review we aim to summarize recent data on the safety and efficacy of primary thromboprophylaxis as well as on venous thromboembolism risk assessment, focusing on ambulatory patients with lung cancer. A potential benefit from prophylactic anticoagulation with low molecular weight heparins in terms of venous thromboembolism risk reduction and increased overall survival in patients with lung cancer, without a significant increase in bleeding risk, has been reported in several studies. Recent studies also reveal promising results of direct oral anticoagulants regarding their efficacy as primary thromboprophylaxis in patients with cancer, including those with lung cancer. However, the use of different study methodologies and the heterogeneity of study populations among the trials limit the extraction of definite results. More randomized, controlled trials, restricted to a well-characterized population of patients with lung cancer, are greatly anticipated. The use of risk assessment tools for stratification of venous thromboembolic risk is warranted. The development of an accurate and practical risk assessment model for patients with lung cancer represents an unmet need.

Acquired von Willebrand Syndrome Complicating Nephrotic Syndrome: A Case of a Patient With Membranous Nephropathy

Acquired von Willebrand syndrome (AVWS) is a rare clinical entity presenting with heterogeneous hemorrhagic manifestations, although some subsets of patients with AVWS may be asymptomatic until they are exposed to major trauma, an invasive procedure, or surgery. We herein report one such case in a 73-year-old male patient with nephrotic syndrome with a prolonged active partial thromboplastin time. We initially did not deal with this distinct abnormal clotting profile seriously, but persistent bleeding after a retroperitoneoscopic-assisted renal biopsy that allowed us to ascribe his nephrotic syndrome to membranous nephropathy fortuitously led to the discovery of concurrent AVWS. We feel that an accurate and prompt diagnosis as well as awareness of the disease remain a challenge for physicians and therefore strongly recommend the further accumulation of experiences similar to our own in a prospective manner. This report underscores the pitfalls associated with determining the bleeding risk, including an insufficient assessment and improper weighting of an abnormal clotting profile prior to the invasive procedure. Several management concerns that emerged in the current case are also discussed.

Retroperitoneal Bleeding: An Experience During Prophylactic Anticoagulation in a Patient With Nephrotic Syndrome

The association between nephrotic syndrome (NS) and a hypercoagulable state has been demonstrated. Controlling the blood clotting activity may therefore be attractive for patients with nephrosis in terms of thromboembolism prophylaxis. We herein report a 75-year-old woman with minimal change disease who developed pains in the right back, groin, and thigh because of retroperitoneal bleeding during prophylactic anticoagulation with unfractionated heparin. Although this procedure has not been accepted as the standard of care for patients with nephrosis, pharmacologic prophylaxis may already be practiced empirically, as in the present patient. We believe that our experience highlights the pitfalls of such a management in patients with nephrosis, implying the need for a diagnostic strategy for identifying those patients with NS who can benefit from prophylactic anticoagulation. Several concerns that emerged in this case are also discussed.

Presumed paradoxical embolus in a patient with diabetic ketoacidosis

Thrombotic complications figure among the most frequent causes of mortality in diabetic ketoacidosis (DKA) and hyperosmolar state. We report the case of a 55-year-old woman presenting with DKA whereby a newly discovered patent foramen ovale was found due in part to the observation of bilateral deep vein thrombosis in legs, bilateral multiple pulmonary embolisms, and left subclavian acute artery thrombosis. Diabetes is known as a hypercoagulability state, and DKA is rising as a risk factor for vascular events. The importance of prophylactic anticoagulation should be emphasized in this setting.

Pulmonary embolism in intensive care unit: Predictive factors, clinical manifestations and outcome

OBJECTIVE:

To determine predictive factors, clinical and demographics characteristics of patients with pulmonary embolism (PE) in ICU, and to identify factors associated with poor outcome in the hospital and in the ICU.

METHODS:

During a four-year prospective study, a medical committee of six ICU physicians prospectively examined all available data for each patient in order to classify patients according to the level of clinical suspicion of pulmonary thromboembolism. During the study periods, all patients admitted to our ICU were classified into four groups. The first group includes all patients with confirmed PE; the second group includes some patients without clinical manifestations of PE; the third group includes patients with suspected and not confirmed PE and the fourth group includes all patients with only deep vein thromboses (DVTs) without suspicion of PE. The diagnosis of PE was confirmed either by a high-probability ventilation/perfusion (V/Q) scan or by a spiral computed tomography (CT) scan showing one or more filling defects in the pulmonary artery or in its branches. The diagnosis was also confirmed by echocardiography when a thrombus in the pulmonary artery was observed.

RESULTS:

During the study periods, 4408 patients were admitted in our ICU. The diagnosis of PE was confirmed in 87 patients (1.9%). The mean delay of development of PE was 7.8 ± 9.5 days. On the day of PE diagnosis, clinical examination showed that 50 patients (57.5%) were hypotensive, 63 (72.4%) have SIRS, 15 (17.2%) have clinical manifestations of DVT and 71 (81.6%) have respiratory distress requiring mechanical ventilation. In our study, intravenous unfractionated heparin was used in 81 cases (93.1%) and low molecular weight heparins were used in 4 cases (4.6%). The mean ICU stay was 20.2 ± 25.3 days and the mean hospital stay was 25.5 ± 25 days. The mortality rate in ICU was 47.1% and the in-hospital mortality rate was 52.9%. Multivariate analysis showed that factors associated with a poor prognosis in ICU are the use of norepinephrine and epinephrine. Furthermore, factors associated with in-hospital poor outcome in multivariate analysis were a number of organ failure associated with PE ≥ 3.

Moreover, comparison between patients with and without pe showed that predictive factors of pe are: acute medical illness, the presence of meningeal hemorrhage, the presence of spine fracture, hypoxemia with PaO₂/FiO₂ ratio <300 and the absence of pharmacological prevention of venous thromboembolism.

CONCLUSION:

Despite the high frequency of DVT in critically ill patients, symptomatic PE remains not frequently observed, because systematic screening is not performed. Pulmonary embolism is associated with a high ICU and in-hospital mortality rate. Predictive factors of PE are acute medical illness, the presence of meningeal hemorrhage, the presence of spine fracture, hypoxemia with PaO₂/FiO₂ < 300 and the absence of pharmacological prevention of venous thromboembolism.