Introduction
COVID-191 has spread around the world. With the efforts of various countries and international organizations, the epidemic has gradually controlled, but there are still no specific drugs for COVID-19. Improving symptoms and preventing further exacerbation of the disease has become critical to clinical treatment.
Most of studies have shown that D-Dimer levels in death with COVID-19 are increased significantly2, suggesting a possibility of the complication of venous thromboembolism (VTE). Autopsy found many microscopic lung thrombis3 and deep vein thrombosis (DVT) rates up to 25% in severe COVID-19 clinical findings4 indicating the risk of VTE is high in COVID-19. The COVID-19 is highly infectious and pathogenic which has increased health care workers’ exposure risk in traditional approach for VTE diagnosis. In this special period, increasing the clinical awareness and diagnosis of VTE, focusing on the occurrence of early-stage clinical symptoms, using available laboratory test to evaluate the condition, and beginning anticoagulant therapy early5 while ensuring the safety is of great importance.
Current studies conducted that anticoagulant therapy can reduce COVID-19 mortality and improve patient prognosis6, but there are separate opinions about the timing of preventive anticoagulant therapy. Through the retrospective study, our team analyzed the dynamic changes of D-dimer under different illness conditions and the prognosis of anticoagulant therapy at different D-dimer levels. The aim of our study was to analyze the clinical significance of D-Dimer in predicting illness severity and guiding anticoagulant therapy in COVID-19.