How long should Acetylsalicylic acid (Aspirin) be held prior to Fine Needle Aspiration (FNA)?

From the Guidelines

Aspirin should be held for at least 5 days prior to Fine Needle Aspiration (FNA) to minimize the risk of bleeding, as recommended by the French Haute Autorité de la santé (HAS) 1.

Important Considerations

• The time required for the full recovery of thromboxane A2 synthesis is about 10 days, but recovery does not need to be total for the complete correction of the platelet functions that depend on thromboxane A2 synthesis 1.
• Interindividual variability in correction of platelet function explains why not all subjects have complete correction after four days 1.
• For procedures with a high risk of bleeding, it is proposed that invasive procedures should be performed only after five days of aspirin washout 1.

Patient Factors

• Faster recovery of aspirin-inhibited platelet function may occur in some patients, e.g. due to accelerated platelet turnover, such as diabetics, patients with high weight, and those with thrombocytosis in a setting of myeloproliferative neoplasia 1.
• The association between results of platelet function tests and bleeding risk is not straightforward, and the haemostatic safety threshold guaranteeing the absence of perioperative risk of bleeding associated with aspirin treatment has not been established 1.

Management

• Other antiplatelet medications and anticoagulants should also be reviewed and managed accordingly to ensure patient safety during the procedure.
• It's best to err on the side of caution and consider holding aspirin for 7 to 10 days if possible, especially if the patient is taking higher doses of aspirin 1.

From the Research

Holding Acetylsalicylic Acid (Aspirin) Prior to Fine Needle Aspiration (FNA)

• The duration for which Acetylsalicylic acid (Aspirin) should be held prior to Fine Needle Aspiration (FNA) is a topic of discussion among medical professionals.
• According to the study 2, there is good evidence supporting discontinuation of low-dose aspirin for high-risk and moderate-risk procedures for at least 3 days.
• Another study 3 suggests that aspirin should be withdrawn 5-10 days in advance for certain types of surgery, such as neurosurgery, but there is no scientific evidence for the withdrawal of aspirin in all patients 5-10 days prior to surgery.
• A study on ultrasound-guided fine needle aspiration of thyroid lesions 4 found that the procedure can be safely performed on patients taking antithrombotic agents, including aspirin, without an increase in adverse outcomes.
• Similarly, a study on endoscopic ultrasound-guided fine-needle aspiration 5 found a low incidence of bleeding events in patients receiving antithrombotic treatment, including aspirin.
• However, a study on spine surgery 6 recommends stopping low-dose aspirin 10 days or longer prior to surgery to avoid postoperative epidural hematoma/paralysis.

Recommendations

• The decision to hold aspirin prior to FNA should be based on individual patient risk factors and the type of procedure being performed.
• For low-risk procedures, aspirin may not need to be discontinued, while for high-risk procedures, discontinuation for at least 3 days may be recommended 2.
• Ultimately, the decision to hold aspirin should be made on a case-by-case basis, taking into account the patient's medical history and the potential risks and benefits of discontinuing aspirin therapy 2, 3, 4, 5, 6.