Table 1.
Main recommendations endorsed by International institutions or scientific societies on antithrombotic therapies in COVID-19
| Institution [ref] | Setting | Recommendation |
|---|---|---|
| WHO [11] | VTE prophylaxis | Recommended with LMWH [preferred] OD or UFH 5000 IU sc BID or TID in adolescents and adults without contraindications |
| ISTH [12] | VTE prophylaxis in all hospitalized pts. | Recommended with LMWH at prophylactic dose unless contraindicated (i.e., active bleeding, plt < 25 × 109/L; monitoring advised in severe renal impairment; abnormal PT or APTT is not a contraindication) |
| SISET [13] | VTE prophylaxis in all hospitalized pts. |
Strongly recommended with LMWH, UFH, or fondaparinux at doses indicated for VTE prophylaxis Intermediate-dose LMWH (i.e., enoxaparin 4,000 IU BID) can be considered on an individual basis in patients with multiple risk factors for VTE (i.e., BMI > 30, previous VTE, active cancer, etc.). Therapeutic doses of UFH or LMWH not supported by evidence outside of proven VTE |
| VTE prophylaxis after hospital discharge | Suggested at home for 7–14 days after hospital discharge or in the pre-hospital phase, in case of pre-existing or persisting VTE risk factors | |
| Swiss Society of Hematology [14] | VTE prophylaxis in all hospitalized pts. | Recommended according to a risk stratification score, unless contraindicated, with LMWH if CrCl > 30 ml/min according to the prescribing information; consider an increased dose in overweight patients (> 100 kg). If CrCl < 30 ml/min, UFH SC BID or TID or IV |
| ICU pts. | Intermediate or therapeutic dosing of LMWH or UHF should be considered, according to the bleeding risk, in pts. with a large increase in D-dimers, severe inflammation, or signs of hepatic or renal dysfunction or imminent respiratory failure | |
| Prevention and Treatment of VTE associated with COVID-19 Infection Consensus Statement Group [15] | VTE prophylaxis in severe or critically ill pts. | Strongly recommended with LMWH in pts. at low or moderate risk of bleeding and with no contraindication |
| VTE prophylaxis in mild and moderate pts. | Recommended with LMWH in pts. assessed to have a high or moderate risk of VTE (PADUA or IMPROVE RAM), in the absence of contraindication | |
| VTE prophylaxis after hospital discharge | Consider prolonged outpatient VTE prophylaxis with LMWH in pts with persistent risk factors for VTE | |
| VTE treatment | Curative anticoagulant parenteral treatment with LMWH recommended in pts. suspected for VTE, in absence of contraindication | |
| ASH [16] | VTE prophylaxis in all hospitalized pts. | Recommended with LMWH or fondaparinux unless the risk of bleeding is judged to exceed the risk of thrombosis |
| VTE prophylaxis after hospital discharge | Consider extended thromboprophylaxis after discharge using a regulatory-approved regimen (DOAC up to 40 days) | |
|
Anticoagulation Forum [17] |
VTE prophylaxis in non-critically ill hospitalized pts. | Recommended with LMWH standard doses, regardless of VTE risk assessment score |
| VTE prophylaxis in ICU pts. | Recommended with increased doses of heparin (e.g., enoxaparin 40 mg SC BID, enoxaparin 0.5 mg/kg SC BID, UFH 7500 IU SC TID or low-intensity IV | |
| VTE prophylaxis after discharge | Not routinely recommended; consider on a case-by-case basis | |
| CHEST Guidelines [18] | VTE prophylaxis in acutely ill hospitalized pts. | Recommended with LMWH or fondaparinux at standard doses over intermediate or full treatment dosing or over DOAC |
| VTE prophylaxis in critically ill hospitalized pts. |
Recommended with LMWH of UFH over fondaparinux or DOAC Suggested current standard dose over intermediate or full treatment dosing |
|
| VTE prophylaxis after hospital discharge | Recommended inpatients prophylaxis only over inpatient plus extended prophylaxis after hospital discharge |
WHO World Health Organization, VTE venous thromboembolism, OD once daily, SC subcutaneously, BID twice daily, TID three times daily, IV intravenously, ISTH International Society on Thrombosis and Hemostasis, pts patients, SISET Italian Society on Thrombosis and Hemostasis, LMWH low molecular weight heparin, UFH unfractionated heparin, CrCl Creatinine clearance, PT prothrombin time, APTT activated partial thromboplastin time, CrCL creatinine clearance, ICU intensive care unit, ASH American Society of Hematology, DOAC direct oral anticoagulants