Urgent/Emergency Reversal of Anticoagulants: Practical Caveats & Flow
When a case can’t wait, use a conservative, neuraxial-safe frame to think about reversal or rapid offset. For elective planning, see the Conservative Peri-Procedure Plan. For timestamped stop/restart windows, use the calculator.
Rapid flow (high-level)
- Confirm drug & last dose (warfarin vs DOAC vs LMWH/UFH) and procedure urgency.
- Check labs where informative (INR for warfarin; aPTT for UFH; consider anti-Xa/thrombin time context for DOACs).
- If neuraxial/catheters are in play, no anticoagulant dosing with a catheter in place; earliest restart is removal + interval.
- Choose an evidence-based reversal/offset path with Hematology/Anesthesia/Pharmacy support.
Warfarin — caveats
| Tool | Use case | Caveats |
|---|---|---|
| Vitamin K | Elective/semi-urgent INR correction | Slower than PCC; transient warfarin resistance; plan re-anticoagulation timing. |
| 4-factor PCC | Urgent major bleed or cannot delay high-risk procedure | Rapid INR correction; thrombotic risk exists; usually with vitamin K; availability varies. |
DOACs — caveats
| Agent | Targets | Caveats |
|---|---|---|
| Idarucizumab | Dabigatran | Rapid neutralization; watch for rebound if absorption continues; renal function matters; inventory-dependent. |
| Andexanet alfa | Apixaban / Rivaroxaban | Anti-Xa reversal; infusion logistics/cost vary; post-reversal thrombosis risk discussed in literature. |
| PCC (off-label) | Factor Xa inhibitors (when antidote unavailable) | Signal of benefit in some settings; practice varies; balance thrombotic risk/benefit. |
Heparins — caveats
| Agent | Targets | Caveats |
|---|---|---|
| Protamine | UFH (full), LMWH (partial) | Rapid for UFH; only partial for LMWH; watch for hypotension/hypersensitivity; coordinate anesthesia. |
| Stop/verify aPTT | UFH infusion | Stopping 4–6 h pre-procedure with normalization of aPTT may suffice for many urgent (not emergent) cases. |
Neuraxial notes
- No anticoagulant dosing while an epidural/spinal catheter is in place.
- Earliest restart: LMWH +4 h; UFH infusion +1 h (and normal aPTT). For DOACs, use catheter removal + a conservative interval and the later of that vs baseline window.
- If renal function is poor (esp. dabigatran CrCl <30), avoid neuraxial if possible or redesign the plan.
Need timestamps and renal/catheter gating? Use the AnticoagPlanner calculator for patient-specific stop/restart plans with explicit sources.
Sources (for verification, not reproduction)
- MD Anderson Cancer Center. Peri-Procedure Anticoagulants, V8 (approved 07/15/2025). Institutional clinical algorithm.
- ASRA/Stanford institutional neuraxial catheter timing summaries (for catheter-removal intervals where institutional norms apply).
Disclaimer: Educational content. This supports, not replaces, clinical judgment. Confirm local policy and anesthesia guidance for neuraxial catheters. Use the calculator for exact timestamps.