How long should I withhold aspirin (acetylsalicylic acid) before a surgical procedure?

Perioperative Management of Aspirin Before Surgery

For most elective surgeries, aspirin should be discontinued ≤7 days before the procedure, with the exact timing depending on the type of surgery and patient's thrombotic risk. 1

Timing of Aspirin Discontinuation by Surgery Type

High Bleeding Risk Procedures

• Neurosurgery/Spinal Surgery: Stop aspirin 7 days before surgery 1, 2
• Intracranial Surgery: Stop aspirin 7 days before surgery 1, 2

Moderate to Low Bleeding Risk Procedures

• Non-cardiac surgery: Stop aspirin ≤7 days before surgery (typically 3-5 days) 1
• Coronary Artery Bypass Grafting (CABG): Continue aspirin throughout perioperative period 1
• Minor dental/dermatologic procedures: Continue aspirin throughout perioperative period 1
• Cataract surgery: Continue aspirin throughout perioperative period 1

Considerations for Specific Patient Populations

Patients with High Cardiovascular Risk

• Secondary prevention of cardiovascular disease: Consider continuing aspirin for moderate-high risk patients 1
• Coronary stents placed within 6-12 weeks: Either continue both antiplatelet agents or stop one agent 7-10 days before surgery 1

Patients with Low Cardiovascular Risk

• Primary prevention: Stop aspirin 7 days before surgery 1

Rationale for Recommendations

The American College of Chest Physicians (ACCP) 2022 guidelines recommend stopping aspirin ≤7 days before elective surgery rather than 7-10 days 1. This updated recommendation is based on evidence that:

1. While aspirin irreversibly inhibits platelet function for the platelet's lifespan (7-10 days), sufficient hemostatic competence may be achieved earlier
2. Recovery of platelet function doesn't need to be complete for most surgeries 1
3. After 3 days of aspirin washout, there is often sufficient improvement in platelet function for most procedures 1

However, for procedures with high bleeding risk (neurosurgery, spinal surgery), where even minor bleeding can cause severe complications, complete correction of platelet function is necessary, requiring 5-7 days of aspirin discontinuation 1, 2.

Special Considerations

• Urgent surgeries: If surgery cannot be delayed, proceed with awareness of increased bleeding risk
• Coronary stents: For patients with recent stent placement, delaying elective surgery is preferred (at least 6 weeks for bare-metal stents, 6 months for drug-eluting stents) 1
• Resumption of aspirin: Resume aspirin within 24 hours after surgery when adequate hemostasis is achieved 1

Common Pitfalls to Avoid

1. Unnecessarily long aspirin discontinuation: The traditional 10-day washout period is excessive for most surgeries 3
2. Inappropriate continuation: Continuing aspirin for high bleeding risk procedures like neurosurgery
3. Failure to resume aspirin promptly: Delayed resumption increases thrombotic risk
4. One-size-fits-all approach: Not considering both the bleeding risk of the specific procedure and the patient's thrombotic risk

The STRATAGEM trial found no significant difference in major thrombotic or bleeding events between preoperative maintenance or interruption of aspirin in patients undergoing intermediate or high-risk non-cardiac surgery 4, suggesting that for many procedures, the decision can be based on individual risk assessment rather than a universal rule.