What is the recommended time to hold Heparin (unfractionated heparin) infusion before a procedure?

From the Guidelines

Heparin infusion should be held 4 to 6 hours before a procedure, as recommended by the American College of Cardiology/American Heart Association guidelines. This recommendation is based on the guidelines for the management of patients with valvular heart disease, which suggest stopping therapeutic doses of intravenous unfractionated heparin (UFH) 4 to 6 hours before the procedure 1. The timing of heparin discontinuation depends on the patient's risk of thrombosis and the type of procedure being performed.

Key Considerations

• For patients at high risk of thrombosis, therapeutic doses of intravenous UFH should be started when the INR falls below 2.0, typically 48 hours before surgery, and stopped 4 to 6 hours before the procedure 1.
• The decision to hold heparin infusion for a longer or shorter period should be individualized based on the patient's renal function, as heparin clearance is delayed in patients with renal impairment.
• Before proceeding with the intervention, it's advisable to check the activated partial thromboplastin time (aPTT) to confirm normalization of coagulation parameters.

Procedure-Specific Considerations

• For urgent procedures, protamine sulfate can be administered to reverse heparin's effects more rapidly.
• After the procedure, heparin can typically be resumed once hemostasis is confirmed, with the exact timing depending on the bleeding risk associated with the procedure. The guidelines emphasize the importance of balancing the risk of thrombosis with the risk of bleeding when managing anticoagulation in patients undergoing procedures 1.

From the Research

Heparin Infusion Recommendations

The recommended time to hold Heparin (unfractionated heparin) infusion before a procedure is not explicitly stated in the provided studies. However, some studies provide guidance on the management of anticoagulants before and after procedures:

• The study 2 suggests that for high-risk procedures, heparin infusions can be used to maintain some degree of anticoagulation, but it does not specify the exact timing of when to hold the infusion.
• The study 3 found that heparin administration before general surgery is associated with a reduction in thromboembolic events, and the optimal time to start heparin seems to be 1 to 10 hours before the time of incision.
• The study 4 compared brief versus prolonged heparin infusion after successful reperfusion in acute myocardial infarction and found that prolonged heparin therapy does not protect against rethrombosis and is associated with a higher rate of bleeding complications.

Key Considerations

When considering the timing of heparin infusion, the following factors should be taken into account:

• The type of procedure and the associated risk of bleeding
• The patient's underlying condition and risk of thromboembolism
• The use of other anticoagulants or antiplatelet agents
• The potential for bleeding complications or thromboembolic events

Study Findings

The studies provide the following findings related to heparin infusion:

• Heparin can be used to prevent venous thromboembolism in moderate-risk patients 5
• Heparin can be used to treat active venous thromboembolism or the peri-infarctional state 5
• Prolonged heparin therapy may not be necessary in low-risk patients after successful reperfusion 4
• Fondaparinux can be used as an alternative to heparin in patients with heparin-induced thrombocytopenia type II 6