Machine Learning to Calculate Heparin Dose in COVID-19 Patients with Active Cancer

To realize a machine learning (ML) model to estimate the dose of low molecular weight heparin to be administered, preventing thromboembolism events in COVID-19 patients with active cancer. Methods: We used a dataset comprising 131 patients with active cancer and COVID-19. We considered five ML models: logistic regression, decision tree, random forest, support vector machine and Gaussian naive Bayes. We decided to implement the logistic regression model for our study. A model with 19 variables was analyzed. Data were randomly split into training (70%) and testing (30%) sets. Model performance was assessed by confusion matrix metrics on the testing data for each model as positive predictive value, sensitivity and F1-score. Results: We showed that the five selected models outperformed classical statistical methods of predictive validity and logistic regression was the most effective, being able to classify with an accuracy of 81%. The most relevant result was finding a patient-proof where python function was able to obtain the exact dose of low weight molecular heparin to be administered and thereby to prevent the occurrence of VTE. Conclusions: The world of machine learning and artificial intelligence is constantly developing. The identification of a specific LMWH dose for preventing VTE in very high-risk populations, such as the COVID-19 and active cancer population, might improve with the use of new training ML-based algorithms. Larger studies are needed to confirm our exploratory results.

Acute Pulmonary Embolism Post COVID-19 Pneumonia – A Case Report

COVID-19 has been associated with multiple venous thromboembolism events such as pulmonary embolism and deep vein thrombosis. Here we report a 64-year male with COVID-19 pneumonia who developed pulmonary thromboembolism following the COVID illness. This patient developed VTE complication in spite of receiving anti-coagulation therapy during admission. This case brings out the need for evidence-based post-discharge VTE prophylaxis approach and guidelines in patients who recover from COVID-19.

Venous thromboembolism events in patients with advanced cancer on immune checkpoint inhibitors

Aim: To evaluate the correlation between venous thromboembolism events (VTEs) and immune checkpoint inhibitor (ICI)-based regimens. Methods: This is a retrospective study of 403 patients with advanced cancer on ICI-based regimens. Results: We report 8% VTE incidence post-ICI initiation over a median of 11.1 months of follow-up. Compared with single-agent ICI, dual-ICI was significantly correlated with higher incidence of VTE (odds ratio [OR]: 4.196, 95% CI: 1.527–11.529, p = 0.005), but chemotherapy–immuno-oncology combination was not (OR: 1.374, 95% CI: 0.285–6.632, p = 0.693). Subsequent systemic therapy post-ICI was also independently associated with higher VTE incidence (OR: 2.599, 95% CI: 1.169–5.777, p = 0.019). Conclusion: Our findings suggest potential underreporting of VTE incidence in ICI clinical trials. As dual-ICI is becoming more prevalent in cancer management, clinicians should maintain vigilance regarding VTE in patients with advanced cancer on ICI-based regimens.

Blood transfusions increase the risk for venous thromboembolism events following total joint arthroplasty

The association between blood transfusions and thromboembolic events (VTE) following total joint arthroplasty (TJA) remains debatable. Using contemporary institutional data, this study aimed to determine whether blood transfusions increase the risk of VTE following primary and revision TJA. This was a single institution, retrospective cohort study. The clinical records of all patients (n = 34,824) undergoing primary and revision TJA between 2009 and 2020 were reviewed. Demographic variables, co-morbidities, type of chemoprophylaxis and intraoperative factors such as use of tranexamic acid were collected. Clinical notes, hospital orders, and discharge summaries were reviewed to determine if a patient received a blood transfusion. Comprehensive queries utilizing keywords for VTE were conducted in clinical notes, physician dictations, and patient-provider phone-call logs. Propensity score matching as well as adjusted mixed models were performed. After adjusting for various confounders, results from regression analysis showed a significant association between allogenic blood transfusions and risk for developing VTE following primary and revision TJA (OR 4.11, 95% CI 2.53–6.69 and OR 2.15, 95% CI 1.12–4.13, respectively). While this strong association remained significant for PE in both primary (p < 0.001) and revision (p < 0.001) matched cohorts, it was no longer statistically significant for DVT (p = 0.802 and p = 0.65, respectively). These findings suggest that the risk of VTE is increased by approximately three-folds when blood transfusions are prescribed. This association was mainly due to higher symptomatic PE events which makes it even more worrisome. Surgeons should be aware of this association, revisit criteria for blood transfusions and use all means available in the perioperative period to optimize the patients and avoid transfusion.

COVID-19: Impact in endothelial function and therapy with Mesenchymal Stromal Cells

The new pandemic of SARS-CoV-2 Betacoronavirus, has spread worldwide, and infected millions of individuals causing the disease denominated of COVID-19. Further on flu symptoms, due to the high tropism of virus, has most been observed in the COVID-19 pathophysiology: acute heart failure, thromboembolism events, acute renal failure, neurological and liver damage, and multiple organ failure, with special attention to endothelial disfunction. Hence, elucidate whether virus target the endothelium is a crucial step to understand COVID-19 pathogenesis. However, the permissiveness of blood vessels during SARS-CoV-2 infection remains unclear, but regardless endothelial infection, the vascular disfunction may occurred in response to molecular inflammatory signaling triggered by immune cells that attempt to limit infection. Thus, alternative therapies using mesenchymal stromal cells (MSCs) can change this scenario and help critically ill patients. In this reflection, we attempt to discuss COVID-19 pathophysiology with impact in endothelial function and explore the applicability of MSC-based therapies as alternative treatment.

Venous thromboembolism in COVID-19: A systematic review and meta-analysis

Severe coronavirus disease 2019 (COVID-19) is associated with increased risk of venous thromboembolism events (VTE). This study performed a systematic review in PubMed/EMBASE of studies reporting the prevalence of VTE in patients with COVID-19 who were totally screened/assessed for deep vein thrombosis (DVT) and/or for pulmonary embolism (PE). Among 47 candidate studies ( n = 6459; 33 in Europe), 17 studies ( n = 3973; weighted age 63.0 years, males 60%, intensive care unit (ICU) 16%) reported the prevalence of PE with a pooled estimate of 32% (95% CI: 25, 40%), and 32 studies ( n = 2552; weighted age 62.6 years, males 57%, ICU 49%) reported the prevalence of DVT with a pooled estimate of 27% (95% CI: 21, 34%). A total of 36 studies reported the use of at least prophylactic antithrombotic treatment in the majority of their patients. Meta-regression analysis showed that the prevalence of VTE was higher across studies with a higher percentage of ICU patients and higher study population mean D-dimer values, and lower in studies with mixed dosing of anticoagulation in ⩾ 50% of the population compared to studies with standard prophylactic dosing of anticoagulation in < 50% of the population. The pooled odds ratio for death in patients with COVID-19 and VTE versus those without VTE (17 studies, n = 2882) was 2.1 (95% CI: 1.2, 3.6). Hospitalized patients with severe COVID-19 are at high VTE risk despite prophylactic anticoagulation. Further research should investigate the individualized VTE risk of patients with COVID-19 and the optimal preventive antithrombotic therapy. PROSPERO Registration No.: CRD42020185543.