From the Guidelines
Subcutaneous heparin should be stopped 24 hours before surgery for therapeutic doses and 12 hours before surgery for prophylactic doses, as recommended for low molecular weight heparin (LMWH) 1. When considering the management of antithrombotic therapy in the perioperative period, it's crucial to balance the risk of thrombosis against the risk of bleeding. The American College of Chest Physicians provides evidence-based guidelines for this management 1.
Key Considerations
- The timing of heparin cessation depends on the type of heparin and the dose, with therapeutic doses of LMWH requiring cessation 24 hours before surgery and prophylactic doses requiring cessation 12 hours before surgery 1.
- For patients receiving bridging anticoagulation with therapeutic-dose SC LMWH, administering the last preoperative dose 24 hours before surgery is recommended to minimize postoperative bleeding risk 1.
- Resumption of heparin therapy post-surgery should be tailored to the individual patient's risk factors, including the type of surgery and the patient's bleeding and thrombotic risks 1.
Clinical Application
In clinical practice, the decision to stop subcutaneous heparin before surgery must consider the patient's overall clinical context, including renal function, which can affect the half-life of LMWH, and the specific surgical procedure, which influences bleeding risk 1.
- Patients with impaired renal function may require earlier cessation of LMWH due to the prolonged half-life of the drug in this population 1.
- For surgeries associated with high bleeding risk, it may be necessary to delay resuming therapeutic-dose LMWH until 24 hours after surgery to ensure adequate hemostasis 1.
From the Research
Subcutaneous Heparin and Surgery
- The decision to stop subcutaneous heparin before surgery depends on various factors, including the type of surgery, patient's risk factors, and the intensity of prophylaxis required 2.
- There is no direct evidence in the provided studies that specifically addresses when to stop subcutaneous heparin before surgery.
- However, studies have compared different dosing intervals of heparin for venous thromboembolism (VTE) prophylaxis, such as every 8 hours and every 12 hours, and found no significant differences in bleeding rates or therapy failure rates 3.
Venous Thromboembolism Prophylaxis
- Venous thromboembolism is a major risk for surgical patients during the perioperative period, and prevention remains a critical component of surgical patient care 2.
- Low molecular weight heparins and fondaparinux have been the cornerstones for prevention of VTE in acutely ill medical patients for almost two decades 4.
- Standard subcutaneous dosing of unfractionated heparin for VTE prophylaxis in surgical ICU patients may lead to subtherapeutic levels of factor Xa inhibition 5.
Comparison of Thromboprophylaxis Medications
- A systematic review and meta-analysis compared fondaparinux and low molecular weight heparin for thromboprophylaxis after hip and knee arthroplasty, and found that fondaparinux showed a statistically significant reduction in the risk of VTE and deep venous thrombosis (DVT) compared to LMWH 6.
- However, fondaparinux was associated with an increased risk of major bleeding, surgical site bleeding, and postoperative transfusions 6.