What is the treatment for a patient on Coumadin (warfarin) presenting with sudden onset bruising from the axilla down to the wrist?

Treatment for Sudden Onset Bruising in a Patient on Warfarin

For a patient on warfarin presenting with sudden onset extensive bruising from axilla to wrist, immediate assessment of INR and implementation of appropriate reversal strategy based on INR level and bleeding severity is required.

Initial Assessment

• Check INR immediately
• Assess vital signs for hemodynamic stability
• Evaluate extent and progression of bruising
• Determine if there are other sites of bleeding
• Review medication history for potential drug interactions (especially NSAIDs, antibiotics)

Management Algorithm Based on INR and Bleeding Severity

For Significant Bruising with Non-Life-Threatening Bleeding:

1. If INR is 5-9 with significant bruising:

   • Omit next 1-2 doses of warfarin
   • Administer oral vitamin K₁ 1-2.5 mg 1
   • Monitor INR within 24 hours
   • Restart warfarin at lower dose when INR returns to therapeutic range

2. If INR is >9 but <20 with significant bruising:

   • Hold warfarin
   • Administer oral vitamin K₁ 3-5 mg 1
   • Monitor INR every 12-24 hours
   • Expect INR reduction within 24-48 hours

3. If INR is ≥20 or bruising is rapidly progressing:

   • Hold warfarin
   • Administer vitamin K₁ 10 mg by slow intravenous infusion
   • Consider fresh frozen plasma (FFP) or prothrombin complex concentrate (PCC) 1

For Life-Threatening Bleeding (hemodynamic instability, expanding hematoma):

• Hold warfarin
• Administer vitamin K₁ 10 mg by slow intravenous infusion
• Administer prothrombin complex concentrate (PCC) - preferred over FFP 1
• Consider blood transfusion if significant blood loss has occurred 2

Advantages of PCC over FFP for Serious Bleeding

PCC is preferred over FFP for several reasons 1:

• Faster reconstitution
• Smaller volume required
• No need for ABO compatibility testing
• Rapid onset of action
• Lower risk of transfusion-related complications
• Faster correction of INR

Monitoring After Initial Treatment

• Repeat INR at 24 hours after vitamin K administration
• Monitor for continued expansion of bruising
• Assess for development of compartment syndrome (especially with extensive arm bruising)
• Additional vitamin K may be given if INR remains elevated after 24 hours 1

Considerations for Restarting Anticoagulation

• Identify and address the cause of elevated INR (drug interactions, dietary changes, etc.)
• Restart at a lower dose once INR approaches therapeutic range
• If high-dose vitamin K was used, heparin bridging may be required until warfarin becomes effective again 1
• Consider alternative anticoagulants if appropriate

Potential Complications to Monitor

• Compartment syndrome in the affected arm
• Progression to skin necrosis (rare but serious complication of warfarin) 2, 3
• Rebound thrombosis after anticoagulation reversal
• Warfarin resistance after vitamin K administration

Common Pitfalls to Avoid

1. Delaying INR measurement in a patient with extensive bruising
2. Using excessive vitamin K doses that may cause prolonged warfarin resistance
3. Failing to identify potential drug interactions (especially NSAIDs) 4
4. Overlooking potential compartment syndrome in extensive arm bruising
5. Restarting warfarin at the previous dose after a bleeding episode

The management of warfarin-associated bleeding requires prompt assessment and intervention to prevent progression to more serious complications while balancing the risk of thrombosis from inadequate anticoagulation.