What is the recommended dosing for Deep Vein Thrombosis (DVT) prophylaxis?

From the Guidelines

Deep vein thrombosis (DVT) prophylaxis typically involves enoxaparin 40 mg subcutaneously once daily for most hospitalized medical and surgical patients at risk, as recommended by the most recent guidelines 1.

DVT Prophylaxis Options

• Enoxaparin 40 mg subcutaneously once daily is the preferred option for most patients.
• Unfractionated heparin 5000 units subcutaneously every 8 hours is an alternative option.
• Fondaparinux 2.5 mg subcutaneously once daily is another alternative option.
• Direct oral anticoagulants like rivaroxaban 10 mg daily can also be used.

Special Considerations

• For patients with obesity (BMI >40 or weight >120 kg), the dose of enoxaparin should be increased to 40 mg twice daily.
• For patients with renal impairment (CrCl <30 mL/min), lower doses of enoxaparin (30 mg twice daily or 20 mg once daily) should be used.
• Mechanical prophylaxis with sequential compression devices should be used when pharmacological prophylaxis is contraindicated due to bleeding risk.

Duration of Prophylaxis

• Prophylaxis should continue throughout hospitalization and potentially for 28 days post-discharge for high-risk patients like those undergoing major orthopedic surgery, as suggested by the guidelines 1.
• The duration of prophylaxis may vary depending on the individual patient's risk factors and clinical circumstances.

Rationale

• These medications work by inhibiting various clotting factors in the coagulation cascade, preventing thrombus formation in the deep veins of the legs which could lead to pulmonary embolism, a potentially fatal complication.
• The choice of prophylaxis should be based on the individual patient's risk factors, renal function, and potential drug interactions, as outlined in the guidelines 1.

From the FDA Drug Label

Prophylaxis of DVT Following Hip or Knee Replacement Surgery: 10 mg orally once daily with or without food ( 2. 1) Prophylaxis of VTE in Acutely Ill Medical Patients at Risk for Thromboembolic Complications Not at High Risk of Bleeding: 10 mg once daily, with or without food, in hospital and after hospital discharge for a total recommended duration of 31 to 39 days ( 2.1)

The recommended dosing for DVT prophylaxis is:

• 10 mg once daily with or without food for patients following hip or knee replacement surgery 2
• 10 mg once daily with or without food for acutely ill medical patients at risk for thromboembolic complications, for a total recommended duration of 31 to 39 days 2

From the Research

DVT Prophylaxis Dosing

• The optimal dosing of enoxaparin for DVT prophylaxis has been studied in various clinical trials 3, 4, 5, 6, 7.
• A study published in 1994 found that enoxaparin 40 mg once daily or 30 mg every 12 hours was more effective than 10 mg once daily in preventing DVT in patients undergoing hip replacement surgery 3.
• Another study published in 2004 compared the efficacy and safety of once-daily enoxaparin with unfractionated heparin in the treatment of proximal lower limb DVT, and found that enoxaparin 1.5 mg/kg subcutaneously once daily was at least as effective and safe as conventional treatment with unfractionated heparin 4.
• A prospective observational cohort study published in 2022 found that a fixed dose of enoxaparin 40 mg subcutaneously provided efficient DVT prophylaxis in mixed ICU patients, despite low anti-Xa levels 5.
• A randomized, parallel-group, open-label study published in 2005 compared the efficacy and safety of once-daily subcutaneous enoxaparin in the outpatient setting with intravenous unfractionated heparin in hospital for the treatment of symptomatic DVT, and found that enoxaparin was at least as effective and well tolerated as unfractionated heparin 6.
• A study published in 2018 compared the impact of once- versus twice-daily enoxaparin prophylaxis on risk for venous thromboembolism and clinically relevant bleeding, and found that twice-daily enoxaparin was associated with a significant decrease in 90-day acute venous thromboembolism and a nonsignificant increase in 90-day clinically relevant bleeding 7.

Enoxaparin Dosing Regimens

• Enoxaparin 40 mg once daily or 30 mg every 12 hours has been shown to be effective in preventing DVT in patients undergoing hip replacement surgery 3.
• Enoxaparin 1.5 mg/kg subcutaneously once daily has been shown to be at least as effective and safe as conventional treatment with unfractionated heparin for the treatment of proximal lower limb DVT 4.
• A fixed dose of enoxaparin 40 mg subcutaneously has been shown to provide efficient DVT prophylaxis in mixed ICU patients, despite low anti-Xa levels 5.
• Twice-daily enoxaparin has been shown to be superior to once-daily enoxaparin for 90-day acute venous thromboembolism risk reduction, but may increase clinically relevant bleeding 7.