Intermediate or Prophylactic-Dose Anticoagulation for Venous or Arterial Thromboembolism in Severe COVID-19

Inclusion Criteria: * Confirmed diagnosis of COVID-19 by reverse transcription polymerase chain reaction (RT-PCR) * New admission to eligible CUIMC ICUs within 5 days * Transfer from nonparticipating to participating ICU is eligible if otherwise meets eligibility criteria. * Patients transferred between participating ICUs will maintain initial treatment assignment. * Patients not on therapeutic anticoagulation and who were already admitted to participating ICU within 5 days of trial initiation are additionally eligible. Exclusion Criteria: * Weight under 50kg * Contraindication to anticoagulation in the opinion of the treating clinician including * overt bleeding * platelet count \<50,000 * Bleeding Academic Research Consortium (BARC) major bleeding in the past 30 days * Gastrointestinal (GI) bleeding within 3 months * history of intracranial hemorrhage * Ischemic stroke within the past 2 weeks * craniotomy/major neurosurgery within the past 30 days * cardiothoracic surgery within the past 30 days * intra-abdominal surgery within 30 days prior to enrollment * Head or spinal trauma in the last months * History of uncorrected cerebral aneurysm or arteriovenous malformation (AVM) * Intracranial malignancy * Presence of an epidural or spinal catheter * Recent major surgery within the last 14 days * Decrease in hemoglobin \>3 g/dL over the last 24 hours * Allergic reaction to anticoagulants (e.g. Heparin Induced Thrombocytopenia) as docum…