The Impact of Anticoagulation on COVID-19 (SARS CoV-2) Patient Outcomes: A Systematic Review.

Background: Emerging data suggest that coagulopathy, cytokine storm, and acute respiratory distress syndrome are associated with the 2019 coronavirus disease (COVID-19). The prevalence of hypercoagulable state in these patients is unknown, but appears to be higher compared to those with other critically ill patients. Elevated D-dimer, large blood vessels clots, deep vein thrombosis, pulmonary embolism and disseminated intravascular coagulation have been reported in patients diagnosed with COVID-19 either on admission or during hospitalization and may be predictors of poor outcomes.

Methods: We performed a comprehensive literature review using the search terms of COVID-19; severe acute respiratory syndrome coronavirus-2, coagulopathy, thrombosis and anticoagulation in PubMed, Ovid, google scholar, Medline and EMBASE databases from December 2019 to May 30, 2020.

Results: A total of 64 relevant studies were reviewed; of which, 4 studies met the inclusion criteria and were included for analysis. The majority of the studies were retrospective involving 525 critically ill COVID-19 patients. The most commonly studied anticoagulant administered was low molecular weight heparins. Anticoagulation dosing varied throughout the studies and may be classified as standard venous thromboembolism prophylaxis, intermediate dosing, or full dose anticoagulation. The most studied objective was improvement in coagulopathy. Significant reduction in D-dimer, improvement in coagulopathy markers such as Interlukin-6, fibrinogen degradation product level, as well as lymphocyte count were reported.

Conclusion: Despite the limited quality of studies analyzed, prophylaxis and higher intensity dosed anticoagulation is associated with improved pulmonary oxygenation, decreased coagulopathy markers and decreased mortality in COVID-19 patients.