A Study of the Efficacy of Troxerutin in Preventing Thrombotic Events in COVID-19 Patients

Inclusion criteria

As long as the patient meets all of the following conditions, adult patients aged 18 and above are eligible for admission:

► COVID-19 patients, defined as: positive RT-PCR (upper respiratory tract or lower respiratory tract) for SARS-CoV-2.

Mild COVID-19 patients are defined as:

Symptomatic patients meeting the case definition for COVID-19 without evidence of hypoxia or pneumonia. Common symptoms include fever, cough, fatigue, anorexia, dyspnea, and myalgia. Other nonspecific symptoms include sore throat, nasal congestion, headache, diarrhea, nausea/vomiting, and loss of smell/taste.

Severe COVID-19 patients are defined as:

Adolescents or adults with clinical signs of pneumonia (i.e., fever, cough, dyspnea, tachypnea) plus one of the following:

• Respiratory rate ≥30 breaths/min
• Severe respiratory distress
• Oxygen saturation (SpO₂) ≤90% in room air
• Progressive deterioration of clinical symptoms with lung imaging showing significant progression of lesions (>50%) within 24 to 48 hours.

• Written informed consent provided according to Chinese law (by the patient, legal guardian, or deferred consent in emergencies).

Exclusion criteria

Patients with any of the following conditions will be excluded from the study:

• Pregnant or lactating women.
• Postpartum (within 6 weeks).
• Extreme weight (100 kilograms).
• Clinical need for heparin therapy.
• Bleeding related to coagulation disorders, acute clinically significant bleeding, active gastrointestinal ulcers, or any organic lesions with high bleeding risk.
• Platelet count <50 x 10^9/L.
• Surgery within the last 15 days, or within 24 hours after spinal or epidural anesthesia.
• History of intracranial hemorrhage, large ischemic stroke, known intracranial malformation or tumor, acute infective endocarditis.
• Severe renal impairment (creatinine clearance <30 mL/min).
• Iodine allergy.
• Long-term use of oxygen supplementation.
• Moribund patients or those expected to die during the current hospitalization due to underlying disease.
• Patients deprived of freedom and those undergoing institutional psychiatric care.
• Ward of the state or under guardianship.
• Participation in other anticoagulant intervention studies.