Initiating Heparin DVT Prophylaxis After Holding Apixaban

Pharmacokinetic Considerations

Apixaban has a terminal plasma half-life of 8-14 hours and reaches peak plasma concentration approximately 3 hours after oral administration, according to the American Thoracic Society, as published in Chest 1
When transitioning between anticoagulants, the timing is critical to prevent both excessive anticoagulation and periods of inadequate anticoagulation, as recommended by the European Society of Anaesthesiology 2

For patients who have had apixaban held, prophylactic doses of heparin can be initiated after 12 hours from the last dose of apixaban, as suggested by the European Society of Anaesthesiology 2
This timing allows for sufficient clearance of apixaban to minimize the risk of excessive anticoagulation while providing necessary thromboprophylaxis, based on guidelines from the American College of Chest Physicians and the European Society of Anaesthesiology 1, 2

Unfractionated heparin: 5,000 units subcutaneously every 8 hours or every 12 hours, as recommended by the American Society of Clinical Oncology 3
Enoxaparin: 40 mg subcutaneously once daily, according to guidelines from the National Comprehensive Cancer Network and the American Society of Clinical Oncology 3, 4
Dalteparin: 5,000 units subcutaneously once daily, as suggested by the National Comprehensive Cancer Network and the American Society of Clinical Oncology 3, 4

For patients with renal impairment: Consider using unfractionated heparin instead of LMWH, as LMWH is primarily cleared by the kidneys, according to the American College of Chest Physicians 1
For patients at high risk of bleeding: Consider mechanical prophylaxis (sequential compression devices or foot pumps) until pharmacological prophylaxis is deemed safe, as recommended by the Mayo Clinic 5

If neuraxial anesthesia or epidural catheter is present, special timing considerations apply, with prophylactic doses of LMWH not administered within 10-12 hours before catheter removal, however an alternative source is needed for this fact.

The risk of DVT in hospitalized patients can be as high as 15% without prophylaxis, making timely initiation of thromboprophylaxis important, according to the National Comprehensive Cancer Network 4

Avoid bridging with therapeutic doses: Bridging with therapeutic doses of heparin or LMWH is not recommended when transitioning from apixaban to prophylactic anticoagulation, as suggested by the European Society of Anaesthesiology 2
Avoid measuring drug concentrations: There is no need to measure the concentration of apixaban before initiating prophylactic heparin, according to the European Society of Anaesthesiology 2