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
- 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
- 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
- Viperidae
- 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
- 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.
- Johnston WF et al. Exposure to Macaque Monkey Bite. J Emerg Med. 2015; 49(5): 624-7. PMID: 26281802
- 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.