ABSTRACT
INTRODUCTION: COVID-19 disease is associated with a high risk of thromboembolic events, especially in patients with a severe course of the disease. At the same time, however, there is a risk of bleeding. These complications have a significant impact on patient morbidity and mortality. Thus, determining an optimal approach to thromboembolic disease prophylaxis can be challenging. CASE REPORTS: This paper presents two cases of polymorbid female patients suffering from COVID-19. Both patients experienced retroperitoneal hemorrhage while on low molecular weight heparins in the process of deintensification of the treatment of their moderate to severe disease. Although both patients were treated surgically with a good local effect on the hemorrhage, their deterioration progressed, finally resulting in death in both the cases. CONCLUSION: Despite the proven benefit of prophylaxis of thromboembolic events using low molecular weight heparins in patients with COVID-19, care should be taken to monitor coagulation laboratory parameters in proper time intervals. The risk of a fatal course of bleeding complications is extremely high in critically ill patients and patients with multiple comorbidities.