What is the workup for a dog bite or scratch on the ear?

Management of Dog Bite/Scratch on the Ear

For dog bites or scratches on the ear, immediate wound cleansing with copious amounts of water or saline, followed by prophylactic antibiotics (amoxicillin-clavulanate) for 3-5 days is recommended, along with tetanus prophylaxis and rabies risk assessment. 1

Initial Wound Assessment and Cleaning

1. Immediate wound cleansing:

   • Thoroughly irrigate with copious amounts of warm water or saline solution
   • Continue irrigation until all visible foreign matter is removed
   • Consider using povidone-iodine solution as a virucidal agent 2
   • Avoid using ice directly on the bite wound as it can cause tissue ischemia

2. Wound assessment:

   • Evaluate depth and structures potentially involved
   • Check for signs of infection (redness, swelling, warmth, pain)
   • Assess for cartilage involvement or penetration
   • Document the appearance and size of the wound

Antibiotic Prophylaxis

Antibiotic prophylaxis is strongly indicated for ear bites/scratches because:

• The ear is considered a high-risk location (similar to face) 1
• Ear cartilage involvement increases infection risk
• Potential for cosmetic deformity if infection develops

Recommended antibiotic regimen:

• First-line: Amoxicillin-clavulanate 875/125 mg twice daily for 3-5 days 1
• Alternative options (if penicillin allergic):
  • Doxycycline 100 mg twice daily
  • Clindamycin 300 mg three times daily plus either ciprofloxacin or TMP-SMX 1

Tetanus and Rabies Prophylaxis

1. Tetanus prophylaxis:

   • Administer tetanus toxoid if vaccination is not current (>10 years)
   • Tdap is preferred over Td if not previously given 1

2. Rabies risk assessment:

   • Consult with local health officials to determine if rabies prophylaxis is needed 1
   • Consider the following factors:
     • Vaccination status of the dog
     • Whether the dog is available for 10-day observation
     • Provoked vs. unprovoked attack
     • Local rabies epidemiology

Management Based on Dog Status

1. If dog is owned and vaccinated:

   • Dog should be confined and observed for 10 days 1
   • No rabies prophylaxis needed unless dog develops signs of illness

2. If dog is stray or unknown vaccination status:

   • Attempt to locate and observe the dog if possible
   • If dog cannot be observed, consult local health department regarding rabies risk
   • Consider rabies post-exposure prophylaxis based on local recommendations 1

Special Considerations for Ear Wounds

• Cartilage involvement: If cartilage is exposed or penetrated, more aggressive antibiotic therapy and specialist referral may be needed
• Cosmetic concerns: Consider plastic surgery consultation for complex lacerations or significant tissue loss
• Follow-up: Schedule follow-up within 48-72 hours to assess wound healing and infection status

Wound Closure Considerations

• Small, clean wounds less than 8 hours old may be considered for primary closure
• Puncture wounds or wounds with significant contamination should be left open
• Consider delayed primary closure for high-risk wounds

Pitfalls to Avoid

1. Underestimating infection risk: Ear bites have higher infection rates due to cartilage involvement and poor blood supply
2. Inadequate wound irrigation: Thorough cleaning is essential to prevent infection
3. Inappropriate antibiotic selection: Use antibiotics that cover both aerobic and anaerobic bacteria
4. Neglecting rabies risk assessment: Always evaluate the need for rabies prophylaxis
5. Missing underlying structure damage: Carefully assess for cartilage damage or vascular compromise

Remember that ear bites/scratches are considered high-risk injuries that warrant prophylactic antibiotics and careful follow-up to prevent complications that could lead to cosmetic deformity or infection of cartilage.