From the Guidelines
Heparin infusion should be stopped 4 to 6 hours before a surgical procedure, as recommended for patients at high risk of thrombosis. This guideline is based on the 2008 focused update incorporated into the ACC/AHA 2006 guidelines for the management of patients with valvular heart disease 1.
Key Considerations for Heparin Discontinuation
- For patients at low risk of thrombosis, heparin is usually unnecessary, and warfarin can be stopped 48 to 72 hours before the procedure and restarted within 24 hours after the procedure 1.
- In patients at high risk of thrombosis, therapeutic doses of intravenous UFH should be started when the INR falls below 2.0, stopped 4 to 6 hours before the procedure, and restarted as early after surgery as bleeding stability allows 1.
Monitoring and Adjustments
- Regular monitoring of aPTT or anti-Xa levels helps guide therapy, with heparin being adjusted or stopped when values exceed the therapeutic range.
- Heparin's short half-life allows for rapid clearance after discontinuation, making it useful for situations requiring quick reversal of anticoagulation.
Special Considerations
- Heparin should be discontinued immediately if serious bleeding occurs or if the patient develops heparin-induced thrombocytopenia (HIT).
- When transitioning to oral anticoagulation, heparin should be continued until the INR reaches the therapeutic range for at least 24 hours.
From the FDA Drug Label
If the platelet count falls below 100,000/mm3 or if recurrent thrombosis develops, promptly discontinue heparin, evaluate for HIT and HITT, and, if necessary, administer an alternative anticoagulant. If the coagulation test is unduly prolonged or if hemorrhage occurs, discontinue heparin promptly
Discontinuation of Heparin Infusion should occur under the following conditions:
- Platelet count falls below 100,000/mm3
- Recurrent thrombosis develops
- Hemorrhage occurs
- Coagulation test is unduly prolonged 2 2
From the Research
Discontinuation of Heparin Infusion
The decision to discontinue heparin infusion depends on various factors, including the patient's condition, the risk of thromboembolism, and the introduction of other anticoagulants.
- Heparin is typically continued for 7-10 days, overlapped with warfarin sodium during the last 4-5 days 3.
- An alternative approach is to commence heparin and oral anticoagulants together at the time of diagnosis, and to discontinue heparin on the fourth or fifth day 3.
- For patients with submassive venous thrombosis or pulmonary embolism, 4-5 days of initial heparin therapy may be effective and safe, but this approach requires further evaluation 3.
- In cases where warfarin is used, heparin can be discontinued when the international normalized ratio (INR) is within the therapeutic range, usually after 4-5 days of overlap therapy 4, 5.
Considerations for Discontinuation
When considering discontinuation of heparin infusion, the following factors should be taken into account:
- The risk of thromboembolism and the patient's underlying condition 4, 6.
- The introduction of other anticoagulants, such as warfarin, and the achievement of a therapeutic INR 3, 5.
- The patient's renal function and the potential for heparin accumulation 6.
- The presence of any bleeding complications or other adverse effects 6, 5.
Alternative Anticoagulants
In some cases, low-molecular-weight heparin may be used as an alternative to unfractionated heparin, enabling outpatient treatment for patients with uncomplicated deep-vein thrombosis 6, 7.