What is the prophylaxis protocol for a dog bite?

Dog Bite Prophylaxis Protocol

The essential components of dog bite prophylaxis include immediate wound cleansing with soap and water, antibiotic prophylaxis with amoxicillin-clavulanate for high-risk wounds, tetanus prophylaxis if indicated, and assessment for rabies post-exposure prophylaxis in consultation with local health officials. 1

Initial Wound Management

1. Immediate wound cleansing:

   • Thoroughly wash all bite wounds with soap and water
   • Consider virucidal agents like povidone-iodine solution for irrigation 1
   • This simple measure has been shown to markedly reduce the likelihood of rabies and bacterial infections 1

2. Wound assessment:

   • Examine for foreign bodies and devitalized tissue (remove if present)
   • Document neurovascular function and joint range of motion 2
   • Evaluate depth, location, and type of wound (puncture vs. crush/avulsion)

3. Wound closure considerations:

   • Primary closure may be performed for wounds with low infection risk 2
   • Consider delayed primary closure for higher-risk wounds 3
   • The decision to suture should balance cosmetic factors against infection risk 1

Antibiotic Prophylaxis

Preemptive antimicrobial therapy (3-5 days) is recommended for patients with: 1

• Immunocompromised status
• Asplenia
• Advanced liver disease
• Preexisting or resultant edema of affected area
• Moderate to severe injuries, especially to hand or face
• Injuries that may have penetrated periosteum or joint capsule

First-line antibiotic choice:

• Amoxicillin-clavulanate 875/125 mg twice daily (oral) 1
• Alternative options for penicillin-allergic patients:
  • Doxycycline 100 mg twice daily
  • Clindamycin 300 mg three times daily (but misses Pasteurella multocida)
  • Trimethoprim-sulfamethoxazole (good for aerobes but poor for anaerobes)

Evidence on antibiotic effectiveness:

• Meta-analysis showed 16% infection rate in untreated dog bites with a 44% reduction in infection risk with antibiotics 4
• Most beneficial for high-risk wounds (hand injuries, puncture wounds, immunocompromised patients) 5

Tetanus Prophylaxis

• Evaluate tetanus immunization status
• Administer tetanus toxoid if indicated based on wound characteristics and vaccination history 1

Rabies Post-Exposure Prophylaxis (PEP)

Assessment for rabies risk: 1

• Circumstances of bite (provoked vs. unprovoked)
• Vaccination status of the dog
• Ability to observe the dog for 10 days
• Geographic location (higher risk in developing countries)

For suspected rabies exposure: 1

1. Local wound treatment as described above
2. Human Rabies Immune Globulin (HRIG) - 20 IU/kg body weight
   • Infiltrate full dose around and into wounds if anatomically feasible
   • Inject remaining volume IM at site distant from vaccine administration
3. Rabies vaccine - Five 1-ml doses administered intramuscularly
   • First dose as soon as possible after exposure
   • Additional doses on days 3,7,14, and 28 after first dose
   • For adults: administer in deltoid area (never gluteal)
   • For children: deltoid or anterolateral thigh acceptable

Important considerations:

• Consultation with local health officials is recommended to determine if vaccination should be initiated 1
• Bites that don't break the skin generally don't require rabies PEP 2
• Delays beyond 24 hours in seeking PEP are common and concerning 6
• PEP should begin within 24 hours of exposure when indicated, but can be started regardless of time elapsed if exposure is confirmed 1

Common Pitfalls to Avoid

1. Delaying rabies PEP assessment - Consult with health officials promptly
2. Inadequate wound cleansing - This simple measure significantly reduces infection risk
3. Inappropriate antibiotic selection - Amoxicillin-clavulanate covers both aerobic and anaerobic bacteria
4. Missing deep structure damage - Carefully assess for tendon, nerve, vascular injuries, and joint penetration
5. Overlooking tetanus status - Always evaluate need for tetanus prophylaxis
6. Suturing high-risk wounds - Consider delayed closure for wounds at high risk of infection

By following this protocol, clinicians can significantly reduce morbidity and mortality associated with dog bite injuries through prevention of infection, tetanus, and rabies.