Anticoagulation guidelines

When to stop and restart antiplatelet and anticoagulant drugs around a block or catheter.

Minimum time intervals from the joint ESAIC/ESRA guideline (2022) for neuraxial procedures and deep, non-compressible blocks. The same intervals apply to removing a catheter. "Low dose" means prophylactic and "high dose" means therapeutic. CrCl is creatinine clearance.

Superficial, compressible blocks: may be done while the patient takes anticoagulant or antiplatelet drugs, after weighing the risks; these intervals do not apply.
Deep, non-compressible blocks follow the same intervals as neuraxial procedures. The guideline's Table 2 sorts each block into deep or superficial. Depth from the skin is not the test: it is whether bleeding could be seen and compressed. Check Table 2, and your local policy, for the block you plan.
The same intervals apply to removing a catheter as to inserting a needle.
If the patient takes two drugs, use the longer interval.
Ultrasound guidance and bleeding-risk scores do not shorten the intervals.
After a bloody tap, consider delaying the next dose.
Reversal: prothrombin complex concentrate and vitamin K 10 mg for warfarin; idarucizumab for dabigatran; protamine for unfractionated heparin.

Antiplatelet drugs

Drug	Last dose → needle or catheter removal	Needle or catheter removal → next dose
Aspirin, low dose (up to 200 mg/day)	No interval needed, after a risk–benefit check. A single-shot spinal is preferred to an epidural.	Routine time
Aspirin, high dose	3 days (normal platelet count) to 7 days	6 h
Clopidogrel	5–7 days	75 mg: without delay. 300 mg loading: 2 days. Not while a catheter is in place.
Prasugrel	7 days	24 h. Not while a catheter is in place.
Ticagrelor	5 days	24 h. Not while a catheter is in place.

Heparins and fondaparinux

Drug	Last dose → needle or catheter removal	Needle or catheter removal → next dose
Unfractionated heparin, prophylactic SC	4 h	Routine prophylaxis time
Unfractionated heparin, therapeutic	IV: 6 h. SC: 12 h. And aPTT, anti-Xa or ACT in the normal range.	Therapeutic dose only after the catheter is out; low-dose heparin meanwhile.
LMWH, prophylactic (e.g. enoxaparin 40 mg once daily)	12 h (24 h if CrCl below 30 mL/min)	Routine prophylaxis time
LMWH, therapeutic (e.g. enoxaparin 1 mg/kg twice daily)	24 h (48 h if CrCl below 30 mL/min), or anti-Xa 0.1 IU/mL or less	Therapeutic dose only after the catheter is out; prophylactic LMWH meanwhile.
Fondaparinux 2.5 mg/day	36 h (72 h if CrCl below 50 mL/min)	Routine prophylaxis time
Fondaparinux, therapeutic	Neuraxial not recommended. If unavoidable: about 4 days and calibrated anti-Xa 0.1 IU/mL or less.	Low dose per routine

Vitamin K antagonists

Drug	Last dose → needle or catheter removal	Needle or catheter removal → next dose
Warfarin	About 5 days and INR in the normal range (INR below 1.5 may be acceptable after a risk–benefit check)	Routine time. Not while a catheter is in place; use low-dose LMWH meanwhile.
Acenocoumarol	About 3 days and normal INR	As warfarin
Phenprocoumon	About 7 days and normal INR	As warfarin

Direct oral anticoagulants (low dose = prophylactic, high dose = therapeutic)

Drug	Last dose → needle or catheter removal	Needle or catheter removal → next dose
Dabigatran	Low dose: 48 h. High dose: 72 h. If CrCl below 50 mL/min: proceed when dabigatran level is below 30 ng/mL or thrombin time is normal.	Routine time; therapeutic doses only after the catheter is out.
Rivaroxaban	Low dose: 24 h (30 h if CrCl below 30). High dose: 72 h, or a drug level below 30 ng/mL if CrCl is below 30.	Routine time; therapeutic doses only after the catheter is out.
Apixaban	Low dose: 36 h. High dose: 72 h, or a drug level below 30 ng/mL.	Routine time; therapeutic doses only after the catheter is out.
Edoxaban	Low dose: 24 h (30 h if CrCl below 30). High dose: 72 h.	Routine time; therapeutic doses only after the catheter is out.

Short-acting IV anticoagulants

Drug	Last dose → needle or catheter removal	Needle or catheter removal → next dose
Argatroban, bivalirudin	Stop for 4–5 half-lives (argatroban about 4 h)	Not stated

Source: Kietaibl S, Ferrandis R, Godier A, et al. Regional anaesthesia in patients on antithrombotic drugs: Joint ESAIC/ESRA guidelines. Eur J Anaesthesiol 2022;39:100–132. The full guideline is free on the ESRA guidelines page. Summarised by Nerve Blocks: check the original before acting, and always weigh the individual patient's bleeding and clotting risks.