When should Acetylsalicylic Acid (ASA) be initiated after surgery?

From the Guidelines

Aspirin (ASA) should be initiated as soon as there is no concern over bleeding after surgery, as recommended by the 2024 ESC guidelines for the management of chronic coronary syndromes 1. When considering the initiation of ASA after surgery, several factors must be taken into account, including the patient's bleeding risk, cardiovascular risk, and the specific procedure performed.

• The dose of ASA is typically 81-325 mg daily, with lower doses (81 mg) preferred for most patients to minimize bleeding risk while maintaining antiplatelet effects.
• For patients with high cardiovascular risk or those with coronary stents, ASA may be continued throughout the perioperative period or restarted as soon as hemostasis is achieved.
• In patients undergoing coronary artery bypass grafting (CABG) surgery, resuming ASA within 24 hours after surgery is suggested, as stated in the 2022 American College of Chest Physicians clinical practice guideline 1.
• However, the most recent and highest quality study, the 2024 ESC guidelines, recommends initiating ASA post-operatively as soon as there is no concern over bleeding, which takes precedence over other guidelines 1.
• The decision to restart ASA should balance thrombotic and bleeding risks, considering the specific procedure performed, patient's underlying condition, and any complications during surgery.
• Patients with recent acute coronary syndrome or stent placement generally need earlier ASA resumption, and the timing should be coordinated between the surgeon and other providers involved in the patient's care to ensure optimal outcomes.

From the Research

Initiation of Acetylsalicylic Acid (ASA) after Surgery

• The optimal timing for initiating Acetylsalicylic Acid (ASA) after surgery is not explicitly stated in the provided studies, but the available evidence suggests that ASA can be considered for primary venous thromboembolism (VTE) prophylaxis in orthopaedic patients at high-risk of bleeding complications 2.
• In orthopaedic procedures, such as total hip arthroplasty, total knee arthroplasty, and hip fracture surgery, ASA may be less effective than or as effective as low molecular weight heparin for preventing deep vein thrombosis and pulmonary embolism 3.
• The European guidelines on perioperative venous thromboembolism prophylaxis recommend using ASA in some orthopaedic procedures, considering its potential benefits and risks 3.
• A review of the recent literature suggests that the continuation or discontinuation of ASA perioperatively remains a complicated issue and should be made on a case-by-case risk-benefit analysis 4.
• There is no indication to initiate ASA perioperatively in patients with stable ischemic heart disease as the risks outweigh the benefits 4.

Considerations for ASA Initiation

• The decision to initiate ASA after surgery should be based on the individual patient's risk factors, such as bleeding complications and thromboembolic events 2.
• Extended prophylaxis with ASA up to 4 weeks post-surgery may reduce VTE episodes 2.
• The anti-platelet effect of ASA is substantially reduced after administration of heparin during carotid endarterectomy, which may impact the timing of ASA initiation 5.
• Further studies are needed to clarify the optimal timing and duration of ASA therapy in the perioperative period 6, 4.