Please select the eligibility criteria that correspond to the clinical trial below.
Title: A Pilot Study to Determine the Feasibility of Conducting a Randomized Clinical Trial Comparing Fondaparinux Sodium (Arixtra) Once Daily With Enoxaparin (Lovenox®) Twice Daily With Respect to Preventing VTE After Bariatric Surgery in Obese Patients
Brief Summary: This pilot study is designed to determine the feasibility of conducting a randomized clinical trial comparing fondaparinux sodium (Arixtra) once daily with enoxaparin (Lovenox®) twice daily with respect to preventing deep vein thrombosis (DVT) and pulmonary embolism (PE) after bariatric surgery in obese patients.


Options:
A: Inclusion Criteria:

1. Men or women 18 years or older.
2. Body mass index (BMI) of 35kg/m2 or greater.
3. Undergoing laparoscopic bariatric surgery, i.e., laparoscopic sleeve gastrectomy, laparoscopic Roux-en Y gastric bypass or laparoscopic duodenal switch.

Exclusion Criteria:

1. History of previous deep vein thrombosis.
2. History of previous pulmonary emboli.
3. History of documented clotting/coagulation disorder.
4. History of cancer.
5. Weight \< 50 kg or \> 200 kg or unable to fit in MRI scanner.
6. Presence of metallic foreign bodies
7. Recent history of smoking (within the last year).
8. History of venous stasis disease.
9. History of obesity hypoventilation syndrome.
10. Patients who are unable to lay flat for extended periods of time or are claustrophobic.
11. Patients who have a pacemaker, an implanted defibrillator or certain other implanted or electronic or metallic devices (implanted medical or metallic devices, shrapnel, or metal).
12. History of hypersensitivity reaction to anticoagulation products.
13. History of HIT (Heparin Induced Thrombocytopenia.
14. History of Renal Insufficiency (Creatinine Clearance \< 50).
15. Active clinically significant bleeding.
16. Acute bacterial endocarditis.
17. BMI \> 60.
18. Patients with metallic foreign body or implant (unable to have an MRV study).
B: Inclusion Criteria:

- All adult COVID19+ patients admitted to the ICU from 13th of March until 20th of April 2020.

Exclusion Criteria:

- Patients younger than 18 years old.
C: 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 documented in the electronic health records. Extracorporeal membrane oxygenation (ECMO) support or other mechanical circulatory support.
* Severe chronic liver dysfunction (history of portosystemic hypertension (HTN), esophageal varices, or Child-Pugh class C or above or similar Model For End-Stage Liver Disease (MELD) scores), abnormality in liver function tests (aspartate aminotransferase (AST), alanine aminotransferase (ALT), bilirubin) 5 times greater than upper normal limit.
* A history of congenital bleeding diatheses or anatomical anomaly that predisposes to hemorrhage (e.g. hemophilia, hereditary hemorrhagic telangiectasia)
* Treating physician preference for therapeutic anticoagulation
* Enrollment in other concurrent trials related to anticoagulant or antiplatelet therapy
* Existing treatment with therapeutic anticoagulation during the previous 7 days of hospitalization prior to ICU admission (e.g. for venous thromboembolism (VTE), atrial fibrillation, mechanical valve, etc).
* Do-not-resuscitate (DNR) /do-not-intubate (DNI) or comfort measures only (CMO) orders prior to randomization.
D: Inclusion Criteria:

1. Patients ≥18 years of age providing (possibly through a substitute decision maker) informed consent who require hospitalization anticipated to last ≥72 hours, for microbiologically-confirmed COVID-19, enrolled \< 72 hours of hospital admission or of COVID-19 confirmation

• If the patient is already hospitalized and the COVID-19 diagnosis is due to an outbreak or an incidental finding, then enrollment can occur within 72 hours of a clinical syndrome attributable to COVID-19 that requires continued hospitalization (e.g. new or worsening oxygen requirements or acute kidney injury) which is further anticipated to extend the hospital admission by an additional 72 hours from randomization.

Exclusion Criteria:

1. Patients admitted to an ICU AND receiving organ support (i.e. high flow nasal oxygen, receiving non-invasive or invasive mechanical ventilation, or are requiring vasopressor/inotrope)
2. Patients for whom the intent is to not use pharmacologic thromboprophylaxis
3. Active bleeding
4. Risk factors for bleeding, including:

   1. intracranial surgery or stroke within 3 months;
   2. history of intracerebral arteriovenous malformation;
   3. cerebral aneurysm or mass lesions of the central nervous system;
   4. intracranial malignancy
   5. history of intracranial bleeding
   6. history of bleeding diatheses (e.g., hemophilia)
   7. history of gastrointestinal bleeding within previous 3 months
   8. thrombolysis within the previous 7 days
   9. presence of an epidural or spinal catheter
   10. recent major surgery \<14 days
   11. uncontrolled hypertension (sBP \>200 mmHg, dBP \>120 mmHg)
   12. other physician-perceived contraindications to anticoagulation
5. Platelet count \<50 x10\^9/L, INR \>2.0, or baseline aPTT \>50 (if available per SOC testing)
6. Hemoglobin \<80 g/L (to minimize the likelihood of requiring red blood cell transfusion if potential bleeding were to occur)
7. Acute or subacute bacterial endocarditis
8. History of heparin induced thrombocytopenia (HIT) or other heparin allergy including hypersensitivity
9. Current use of dual antiplatelet therapy
10. Patients with an independent indication for therapeutic anticoagulation
11. Patients in whom imminent demise is anticipated and there is no commitment to active ongoing intervention
12. Anticipated transfer to another hospital that is not a study site within 72 hours
13. Enrollment in other trials related to anticoagulation or antiplatelet therapy

Answer: A