For an adult undergoing elective knee surgery, how many days should clopidogrel be discontinued preoperatively?

Clopidogrel Discontinuation for Elective Knee Surgery

For elective knee surgery, discontinue clopidogrel 5 days before the procedure. This recommendation is consistently supported by multiple high-quality guidelines and provides the optimal balance between minimizing bleeding risk while allowing safe resumption of antiplatelet therapy postoperatively 1, 2.

Evidence-Based Timing

Standard Recommendation: 5 Days

• ACC/AHA guidelines explicitly recommend holding clopidogrel for 5-7 days before elective surgery 1
• The FDA drug label for clopidogrel states: "When possible, interrupt therapy with clopidogrel for five days prior to such surgery" 2
• French perioperative guidelines recommend a last intake of clopidogrel 5 days before surgery 1
• This 5-day window allows for dissipation of the antiplatelet effect, as clopidogrel inhibits platelet aggregation for the lifetime of the platelet (7-10 days) 2

Supporting Clinical Evidence

• Orthopedic-specific data confirms that holding clopidogrel ≥5 days before hip or knee arthroplasty significantly reduces bleeding-related complications 3
• Patients who withheld clopidogrel for 5 or more days had lower rates of reoperation for infection and reduced need for antibiotics for surgical wounds 3
• The CURE trial demonstrated that stopping clopidogrel <5 days before CABG resulted in major bleeding rates of 9.6% versus 6.3% when held appropriately 1

Clinical Context: When Urgent Surgery Cannot Wait

High Thrombotic Risk Scenarios

If the patient has recent acute coronary syndrome or coronary stent placement, the decision becomes more complex and requires risk stratification 4:

• Recent stent (<6 weeks for bare metal, <6 months for drug-eluting): Delay elective surgery if possible 5
• Refractory ischemia with high-risk anatomy: Consider proceeding with surgery without discontinuing clopidogrel, accepting increased bleeding risk 4
• Moderate thrombotic risk: May discontinue clopidogrel for 3-5 days as a compromise 4

If Surgery Cannot Be Delayed

• Surgery can be performed 24 hours after clopidogrel discontinuation with acceptable (though increased) bleeding risk 1
• For urgent CABG specifically, surgery may proceed if the incremental bleeding risk is considered acceptable by experienced surgeons 1

Postoperative Management

Resumption of Clopidogrel

• Restart clopidogrel as soon as hemostasis is achieved postoperatively 2
• Evidence suggests no increase in bleeding events when clopidogrel is resumed immediately after knee arthroplasty 3
• For patients with recent ACS or stent, resumption within 12-24 hours is recommended to prevent recurrent ischemic events 4, 6

Important Caveats and Pitfalls

Common Mistakes to Avoid

• Do not substitute heparin or LMWH for clopidogrel perioperatively - this does not provide adequate protection against coronary or stent thrombosis 6
• Do not perform neuraxial anesthesia (spinal/epidural) in patients on clopidogrel - the thrombotic risk of withdrawal does not justify the hemorrhagic risk of neuraxial blockade 6
• Do not assume all orthopedic procedures require discontinuation - some recent studies suggest continuation may be safe in select patients, though this remains controversial 7, 8

Risk Factors for Increased Bleeding

Patients at higher risk for bleeding-related complications include 3:

• Advanced age
• ASA score of 4
• Revision surgery (versus primary arthroplasty)

Bleeding Management if Surgery Proceeds Early

If surgery must occur <5 days after clopidogrel discontinuation 1, 6:

• Fresh platelet transfusion is the only method to rapidly restore hemostasis (at least 20% of circulating platelets must have normal function) 6
• Platelet transfusions may be less effective if given within 4 hours of loading dose or 2 hours of maintenance dose 2
• Consider antifibrinolytic agents (aminocaproic acid or tranexamic acid) for hemostasis 1

Summary Algorithm

For standard elective knee surgery:

1. Hold clopidogrel 5 days preoperatively 1, 2, 3
2. Continue aspirin if patient is on dual antiplatelet therapy (aspirin can be safely continued) 1
3. Resume clopidogrel when hemostasis is achieved postoperatively 2, 3

For patients with recent stent or ACS:

1. Delay surgery if possible (≥6 weeks for bare metal stent, ≥6 months for drug-eluting stent) 5
2. If surgery cannot be delayed and thrombotic risk is high, consider proceeding without discontinuation 4
3. If intermediate risk, may hold for 3-5 days as compromise 4