Question

Discuss anticoagulation for a patient with prosthetic heart valve :
undergoing non-cardiac surgery.

Hint:

The management of anticoagulation during non-cardiac surgery in patients with prosthetic heart valves involves a balance between preventing thromboembolism and minimizing bleeding risk.

Answer 1

Anticoagulation therapy is crucial for patients with prosthetic heart valves to prevent thromboembolic events. However, the management of anticoagulation during non-cardiac surgery requires careful consideration to balance the risk of thrombosis with the risk of bleeding.
Step 1: Preoperative Management:
1. Discontinuing Anticoagulation: In most cases, oral anticoagulants (such as warfarin) are stopped 5-7 days before surgery to allow the INR (International Normalized Ratio) to normalize.
2. Bridging Therapy: Patients with mechanical prosthetic heart valves may require bridging with low-molecular-weight heparin (LMWH) or unfractionated heparin (UFH) to prevent thromboembolism during the perioperative period.
3. Monitoring: Frequent monitoring of INR and anti-Xa levels is essential to ensure the proper therapeutic range during bridging therapy.
Step 2: Intraoperative Management:
1. Heparinization: Intraoperative heparinization is typically used to prevent clot formation, especially in surgeries with a high risk of bleeding. Heparin is usually discontinued before the end of the procedure.
2. Antidote Availability: In case of excessive bleeding, the availability of protamine sulfate, an antidote to heparin, should be ensured.
Step 3: Postoperative Management:
1. Resuming Anticoagulation: After surgery, anticoagulation is typically resumed as soon as possible, with bridging therapy continued until the patient is stable on warfarin therapy.
2. Patient-Specific Considerations: The decision to continue or adjust anticoagulation should be made based on the patient’s individual risk factors, such as the type of prosthetic valve and the nature of the surgery.