Viral infections provoke the systemic inflammatory response and cause an imbalance between the procoagulant and anticoagulant homeostatic mechanisms. Multiple pathogenic mechanisms are involved, including endothelial dysfunction, increased von Willebrand factor, Toll receptor activation, and tissue factor pathway activation. D-dimer levels greater than 1000 ng / mL are associated with an 18-fold increased risk of mortality. In this context, many patients may require prophylaxis or antithrombotic treatment with low molecular weight heparins. Currently, there is no validated scheme on the dose and timing of the use of antithrombotic drugs.

The study aims to identify the effect of two anticoagulant strategies (prophylactic and therapeutic) on the progression to ventilatory support or death in patients with COVID-19 infection who require hospital care.

Randomized clinical trial in patients with a confirmed infection by COVID-19 who require hospital treatment and subsequent ambulatory surveillance.

Study population. Patients with a diagnosis by PCR of COVID 19, over 18 years of age from the High Specialty Hospital of Ixtapaluca, who meet the inclusion criteria.

Statistic analysis. The student's T-test was carried out to identify the difference in the means of the quantitative variables between the groups. A value of P ≤ 0.05, 95% CI will be considered significant. For the hypothesis test, the chi-square test will be performed, considering a p≤ 0.05, 95% CI value to be significant.

Inclusion Criteria:

• Patients with a diagnosis of COVID-19 infection confirmed by polymerase chain reaction test (RQ-PCR) requiring hospital care for the administration of supplemental oxygen

Exclusion Criteria:

• Patients with life expectancy less than 48hrs
• Patients who require ventilatory support upon admission
• Age over 75 years or with a history of atrial fibrillation
• History of venous or arterial thrombosis
• Severe neurological impairment
• Absence of a primary caregiver to supervise the administration of medication
• History of cerebral hemorrhage
• History of previous use of oral anticoagulants
• History of major surgery 30 days prior to admission
• Uncontrolled systemic arterial hypertension
• KDIGO stage III chronic kidney disease or less
• Hemodialysis or peritoneal dialysis treatment
• History of active or inactive cancer
• Pregnant or postpartum patients