Apixaban Dosing for DVT Prophylaxis

Introduction to Apixaban Prophylaxis

The American Society of Anesthesiologists recommends apixaban 2.5 mg orally twice daily, starting 12-24 hours post-operatively, for 12 days after knee replacement or 35 days after hip replacement, for DVT prophylaxis after major orthopedic surgery 1, 2

For patients undergoing hip or knee replacement surgery, the duration of apixaban treatment varies by procedure: 35 days for hip replacement and 12 days for knee replacement, with a dose of 2.5 mg orally twice daily 1, 2
The dosing applies regardless of age, including patients ≥75 years, with no dose adjustment required for prophylaxis 1, 2

Apixaban 2.5 mg twice daily for 30 days was not superior to enoxaparin for VTE prophylaxis in acutely ill medical patients and was associated with increased major bleeding, according to the American College of Chest Physicians 3, 4, 5
Based on this evidence, apixaban is not recommended for routine medical prophylaxis in hospitalized patients, as stated by the American College of Chest Physicians 3, 4

Patients ≥75 years have an increased risk of gastrointestinal and intracranial bleeding with DOACs compared to younger patients, as reported by the European Society of Cardiology 7
Monitoring for bleeding signs and symptoms is crucial, and patient education is necessary, as recommended by the European Society of Cardiology 7

Check creatinine clearance using the Cockcroft-Gault formula before initiating apixaban therapy, as recommended by the American Society of Anesthesiologists 1, 2
Apixaban has 27% renal elimination, making it more favorable than other DOACs in renal impairment, according to the American Society of Clinical Oncology 3, 4, 6

For patients with CrCl >50 mL/min, the standard prophylactic dose of 2.5 mg twice daily is recommended, as stated by the American Society of Anesthesiologists 1, 2
For patients with CrCl 30-50 mL/min, the standard prophylactic dose of 2.5 mg twice daily is recommended, with no adjustment needed for prophylaxis, according to the American Society of Anesthesiologists 1, 2
For patients with CrCl 15-30 mL/min, apixaban should be used with caution, and for CrCl <15 mL/min, it is contraindicated, as recommended by the American College of Chest Physicians 3, 4

Avoid concurrent use with combined P-glycoprotein and strong CYP3A4 inhibitors, such as ketoconazole or ritonavir, as recommended by the American Society of Anesthesiologists 1, 2, 8
Avoid combination with other anticoagulants, antiplatelets, NSAIDs, SNRIs, or SSRIs due to increased bleeding risk, as stated by the European Society of Cardiology 7

Active bleeding, severe hepatic impairment, and intracranial vascular malformations are contraindications for apixaban use, as recommended by the European Society of Cardiology 7 and the American College of Chest Physicians 3, 4, 6

Do not perform spinal or epidural anesthesia if insufficient discontinuation time has elapsed, as recommended by the American Society of Anesthesiologists 1, 2

Do not use the 5 mg twice daily dose for prophylaxis, as it is the treatment dose for acute VTE, as stated by the American Society of Anesthesiologists 1, 2
Do not apply atrial fibrillation dose-reduction criteria to prophylaxis dosing, as recommended by the American Heart Association 6

For treatment of acute DVT, an initial loading dose of 10 mg orally twice daily for 7 days, followed by a maintenance dose of 5 mg orally twice daily, is recommended, as stated by the American College of Chest Physicians 1, 2, 9