Bites Bites Bites

Animal Bites (Cat, Dog, Monkey, Lizard, Snake)

Quick bullets to prep for in-training, let’s review

Management for ALL animal bites

• X-ray if suspect foreign body
• Remove teeth
• Routine wound care/irrigation
• Update tetanus

Cats

• Pathogens: Pasteurella, Bartonella (cat scratch)
• Treatment
  • Leave the wound open (don’t suture)
  • Strongly consider antibiotics for ALL bites
    •  Amoxicillin/clavulanate
    • PCN allergic: Metronidazole or Clindamycin AND doxycycline, trimethoprim-sulfamethoxazole, moxifloxacin, or cefuroxime

Dogs

• Pathogens: Staph and Strep most predominant, Pasteurella
• Treatment
  • Primary closure if on cosmetic part of the body
  • Antibiotics only if signs of infection, comorbidities, large wounds with gross contamination, wounds on the hand, delayed presentation
    • Amoxicillin/clavulanate
  • Rabies immunoglobulin and vaccination if unknown vaccination status of the dog

Monkey

• Pathogens: Herpes B, Rabies
• Herpes B virus
  • Found in Macaques
  • Fatal if untreated
  • Paresthesias > vesicles > encephalitis
  • High infection rate if untreated
• Treatment:
  • Leave the wound open (don’t suture)
  • Acyclovir for herpes prophylaxis
  • Rabies immunoglobulin and vaccination
  • Consider bacterial prophylaxis

Lizards

• Venomous: Mexican beaded lizard, Gila monster
• Symptoms: Local symptoms, nausea and vomiting, rarely hypotension
• Treatment
  • Observe for 6 hours for systemic effects
  • If hypotensive treat as if anaphylactoid reaction with IVF, epinephrine, steroids, antihistamine
  • Antibiotics only if signs of infection, comorbidities, large wounds with gross contamination

Snakes (US)

• 4 Families
  • Viperidae
    • Crotalinae > Pit vipers
  • Elapidae
  • Colubridae
  • Atractaspidinae
• Viper Family / Pit Vipers

  

  • Includes: Rattlesnakes, cottonmouth, copperheads, western diamondbacks
  • Account for the majority of snake envenomations in North America
  • Identification
    • Triangular shaped head
    • Nostril pits
    • Elliptical pupils
  • Majority are dry bites
  • Local effects
    • Severe pain
    • Edema
    • Erythema
    • Rhabdomyolysis
    • Compartment syndrome
  • Systemic effects
    • Paresthesias
    • Generalized weakness
    • Chest pain
    • Thrombocytopenia, bleeding complications
  • Testing: CBC, fibrinogen, PT, PTT, INR
  • Treatment
    • If asymptomatic observe for 8 -12 hours and repeat blood work
    • Supportive care
    • Moderate to severe envenomations may use Croatlidae polyvalent immune Fab (CroFab)
• Elapidae

  

  • Coral snakes
  • Identification: red on yellow kills a fellow; red on black, venom lack.
  • Symptoms
    • Neurotoxicity – paresthesias, fasciculations, slurred speech, ptosis, diplopia, dysphagia, stridor, paralysis, respiratory failure from neuromuscular blockade
    • Serious neurotoxicity may initially be asymptomatic for a number of hours
  • Treatment
    • Antivenin if strong suspicion of coral snakebite, even in absence of signs of envenomation
    • Admit for monitoring given risk of delayed neurologic manifestations and respiratory failure

Note: All fuzzy animals are nice and haven’t bitten people.

References

1. James Q. Puncture Wounds and Bites. In: Tintinalli JE, Stapczynski J, Ma O, Yealy DM, Meckler GD, Cline DM. eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 8e. New York, NY: McGraw-Hill; 2016. http://accessemergencymedicine.mhmedical.com/content.aspx?bookid=1658&Sectionid=109449392. Accessed January 05, 2017.
2. Johnston WF et al. Exposure to Macaque Monkey Bite. J Emerg Med. 2015; 49(5): 624-7. PMID: 26281802
3. Ruha A, Pizon AF. Native (US) Venomous Snakes and Lizards. In: Hoffman RS, Howland M, Lewin NA, Nelson LS, Goldfrank LR. eds. Goldfrank’s Toxicologic Emergencies, 10e. New York, NY: McGraw-Hill; 2015. http://accessemergencymedicine.mhmedical.com/content.aspx?bookid=1163&Sectionid=65102317. Accessed January 05, 2017.