A patient on warfarin with an INR of 3.9 has a one‑hour nosebleed requiring nasal packing; what is the next step in management?

Management of Warfarin-Associated Epistaxis with INR 3.9

For a patient on warfarin with INR 3.9 and epistaxis requiring nasal packing, proceed with first-line local control measures (nasal packing, compression, cautery) without administering vitamin K or prothrombin complex concentrate, then withhold 1-2 doses of warfarin and recheck INR within 24-48 hours. 1

Immediate Management: Local Control First

The American Academy of Otolaryngology-Head and Neck Surgery explicitly recommends against withholding anticoagulation medications or administering reversal agents (vitamin K, PCC, fresh frozen plasma) prior to attempting first-line interventions for epistaxis, even in anticoagulated patients. 1 This recommendation prioritizes avoiding thrombotic complications over the theoretical benefit of faster bleeding control.

First-line interventions include:

• Nasal packing (already performed in this case) 1
• Nasal compression 1
• Topical vasoconstrictors 1
• Nasal cautery if bleeding source is identified 1

The guideline emphasizes that good local control efforts are paramount because reversal strategies carry significant risks, including thromboembolism from PCC and blood product exposure from plasma transfusions. 1

Warfarin Dose Adjustment

For INR 3.9 without life-threatening bleeding, withhold warfarin for 1-2 doses and monitor serial INR determinations. 2, 3 This INR level is only modestly supratherapeutic and does not warrant vitamin K administration in the absence of major bleeding. 2

• Do not administer vitamin K unless the patient has high-risk bleeding factors (age >65 years, history of prior bleeding, concurrent antiplatelet therapy, renal insufficiency, or alcohol use) and the INR is ≥5.0. 2
• An INR of 3.9 carries elevated bleeding risk, but clinically significant bleeding complications do not rise substantially until INR exceeds 5.0, after which risk escalates exponentially. 2

When Reversal IS Indicated

Reversal agents should be reserved for life-threatening bleeding scenarios, which the guideline defines as: 1, 2

• Hemodynamic instability despite resuscitation
• Bleeding causing airway compromise
• Intracranial, intraspinal, intraocular, pericardial, or retroperitoneal hemorrhage
• Hemoglobin drop ≥2 g/dL with ongoing bleeding

If reversal becomes necessary:

• Administer 4-factor PCC 25-50 U/kg IV (dose based on INR: 25 U/kg for INR 2-4,35 U/kg for INR 4-6) plus vitamin K 5-10 mg IV by slow infusion over 30 minutes, targeting INR <1.5. 2, 4
• PCC achieves INR correction within 5-15 minutes versus hours with fresh frozen plasma. 2
• Vitamin K must be co-administered because factor VII in PCC has only a 6-hour half-life; vitamin K stimulates endogenous production for sustained reversal. 2, 4

Monitoring and Follow-Up

• Recheck INR in 24-48 hours after withholding warfarin to confirm appropriate decline toward therapeutic range. 2
• Once INR returns to 2.0-3.0, resume warfarin at a dose reduced by 10-20% from the previous weekly total. 2
• Investigate precipitating factors: new medications (especially antibiotics), dietary changes in vitamin K intake, intercurrent illness, or changes in hepatic/renal function. 2

Critical Pitfalls to Avoid

• Do not delay local control measures to administer reversal agents; the guideline explicitly states this increases thrombotic risk without proven benefit for non-life-threatening epistaxis. 1
• Avoid high-dose vitamin K (≥10 mg) in non-bleeding situations, as this creates warfarin resistance lasting up to one week and complicates re-anticoagulation. 2
• Do not use fresh frozen plasma if PCC is available; FFP requires hours for effect, needs ABO matching, and carries higher volume overload and infection transmission risks. 2, 4
• Recognize that nasal packing itself provides hemostasis in >95% of cases when properly placed, even with therapeutic anticoagulation. 1