Using new oral anticoagulants in patients undergoing major orthopedic surgery

Area of Science:

• Pharmacology
• Thrombosis
• Orthopedic Surgery

Background:

• Four novel oral anticoagulants (NOACs) are available: apixaban, rivaroxaban, edoxaban, and dabigatran.
• Apixaban and rivaroxaban are FDA-approved for preventing venous thromboembolism after orthopedic surgery.
• Monitoring anticoagulant activity and managing perioperative cessation differ among NOACs.

Purpose of the Study:

• To review the characteristics of NOACs relevant to orthopedic surgery.
• To discuss the implications for perioperative management of patients on NOACs.
• To highlight the lack of readily available assays and antidotes for some NOACs.

Main Methods:

• Literature review of NOACs, focusing on pharmacokinetic and pharmacodynamic properties.
• Analysis of FDA approvals and clinical guidelines for perioperative anticoagulation.
• Comparison of available laboratory monitoring methods and antidote status.

Main Results:

• Apixaban, rivaroxaban, and edoxaban can be monitored via anti-factor Xa assay; dabigatran lacks a widely available assay.
• No NOAC currently has an approved antidote.
• Dabigatran, being 80% renally excreted, requires a 4-5 day cessation period before major orthopedic surgery.
• Apixaban, rivaroxaban, and edoxaban should be discontinued 48 hours preoperatively.

Conclusions:

• Perioperative management of patients on NOACs requires careful consideration of individual drug properties.
• Discontinuation timing varies significantly, particularly for dabigatran compared to apixaban, rivaroxaban, and edoxaban.
• The absence of routine monitoring and antidotes for all NOACs presents clinical challenges in managing bleeding or emergent surgical needs.