When the patient on blood thinners is bleeding or needs emergency surgery. Know the agent, know the antidote, know the dose. Every minute counts in life-threatening hemorrhage.
First-line for life-threatening bleed. Always give with vitamin K 10 mg IV (slow push over 10 min -anaphylaxis risk if fast). PCC effect is temporary (6โ8h); vitamin K provides sustained reversal (6โ24h). FFP is second-line (large volume, slow, infection risk).
Warfarin
Vitamin K (phytonadione) NON-EMERGENT
INR > 10, no bleed: 2.5โ5 mg PO Minor bleed: 5โ10 mg IV slow
6โ24h
PO preferred for non-emergent. IV onset faster but anaphylaxis risk. SubQ absorption is erratic -avoid. Recheck INR in 6โ12h.
Dabigatran (Pradaxa)
Idarucizumab (Praxbind)
5g IV (given as 2 ร 2.5g boluses)
Minutes
Specific monoclonal antibody fragment. Complete reversal within minutes. Single use. If unavailable: 4F-PCC 50 units/kg (partial effect). Hemodialysis removes ~60% of dabigatran (it's dialyzable -unique among DOACs).
Recombinant modified Factor Xa decoy. Very expensive (~$50,000/dose). Low dose if last DOAC dose > 8h ago or low-dose apixaban. High dose if within 8h or rivaroxaban. If unavailable: 4F-PCC 50 units/kg (reasonable alternative, much cheaper).
Unfractionated heparin
Protamine sulfate
1 mg per 100 units heparin given in last 2โ3h. Max 50 mg.
5 min
Full reversal. Risk: hypotension, bradycardia, anaphylaxis (especially in patients with fish allergy, prior protamine, or NPH insulin use -NPH contains protamine).
Enoxaparin (LMWH)
Protamine sulfate
1 mg per 1 mg enoxaparin (if within 8h of dose). 0.5 mg per 1 mg if 8โ12h.
5 min
Only ~60% reversal (protamine neutralizes anti-IIa but not anti-Xa activity of LMWH). If still bleeding โ consider 4F-PCC.
tPA / fibrinolytics
Cryoprecipitate + TXA
Cryo 10 units (fibrinogen > 200). TXA 1g IV over 10 min.
Minutes
Replenish fibrinogen (consumed by tPA). TXA is antifibrinolytic. Also give platelets if < 100K. Aminocaproic acid is alternative to TXA.
๐ง Pre-Procedure Hold Times
Drug
Hold Before Procedure
Resume After
Bridging Needed?
Warfarin (Coumadin)
5 days (INR < 1.5 for most procedures)
12โ24h post (once hemostasis confirmed)
Only if high thrombotic risk: mechanical mitral valve, recent VTE (< 3 mo), CHAโDSโ-VASc โฅ 7. Use enoxaparin 1 mg/kg BID. Most patients do NOT need bridgingBRIDGE, 2015: bridging increased bleeding without reducing thromboembolism.
Apixaban (Eliquis)
48h (72h if high bleed risk or CrCl < 30)
24โ48h post
No bridging needed (short half-life, rapid onset on resumption).
Rivaroxaban (Xarelto)
48h (72h if CrCl < 30)
24โ48h post
No bridging.
Dabigatran (Pradaxa)
48โ72h (CrCl 50โ80). 96h+ if CrCl < 50.
24โ48h post
No bridging. Longer hold in renal impairment (renally cleared).
Enoxaparin (therapeutic)
24h
24โ48h post
N/A
Heparin drip
4โ6h (check aPTT)
When safe per surgeon
N/A
Aspirin (primary prevention)
7 days
24h post
N/A
Aspirin (cardiac stent)
DO NOT STOP
N/A
Continue through procedure unless life-threatening bleed risk. Stopping ASA within 6 months of DES โ stent thrombosis โ MI.
Clopidogrel (Plavix)
5 days
24h post
Consult cardiology before holding if recent stent.