When to Stop Bridging Anticoagulation for Acenocoumarol
Stop bridging anticoagulation (LMWH or UFH) when the INR reaches therapeutic range (≥2.0) for two consecutive days. 1
Timing of Bridging Discontinuation
The key principle is maintaining continuous anticoagulation coverage until acenocoumarol provides adequate protection:
Continue heparin bridging until INR returns to therapeutic levels (≥2.0 for target range 2.5-3.0), as recommended by the European Society of Cardiology and American Heart Association 1
Verify therapeutic INR on two consecutive days before discontinuing bridging therapy to ensure stable anticoagulation 1, 2
Resume acenocoumarol on postoperative day 1-2 at the pre-operative maintenance dose, with some protocols recommending a 50% boost dose for two consecutive days to accelerate INR recovery 1
Practical Implementation
Postoperative Bridging Protocol
Restart LMWH or UFH 1-2 days after surgery depending on bleeding risk, continuing until therapeutic INR is achieved 1
For acenocoumarol specifically, bridging may need to continue slightly longer than warfarin due to its shorter half-life and more variable pharmacokinetics 2, 3
Monitor INR daily once acenocoumarol is resumed until two consecutive therapeutic values are documented 2
Acenocoumarol-Specific Considerations
Acenocoumarol has important differences from warfarin that affect bridging duration:
Acenocoumarol has a shorter half-life (8-11 hours vs 36-42 hours for warfarin), meaning it reaches steady state faster but also requires more careful monitoring 3, 4
Time to therapeutic INR post-procedure significantly influences outcomes - if therapeutic INR is achieved within 5 days, bridging benefit is minimal 3
Acenocoumarol was interrupted 2 days before surgery in successful bridging protocols (compared to 5 days for warfarin), and bridging continued until INR stabilized at therapeutic levels for 2 consecutive days 2
Common Pitfalls to Avoid
Do not stop bridging based on a single therapeutic INR value - require two consecutive therapeutic measurements to ensure stability 1, 2
Do not routinely bridge for single subtherapeutic INR values during routine monitoring - this increases bleeding risk without proven benefit 5
Avoid premature discontinuation of bridging before acenocoumarol effect is established, as this creates a gap in anticoagulation coverage 1
Do not use uneven acenocoumarol dosing (alternating doses on different days), as this causes significant INR fluctuations and makes bridging management more difficult 6