Snake bites: Difference between revisions
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==Background== | ==Background== | ||
[[File:Coral 009.jpg|thumb|[[Coral snake]]]] | |||
[[File:Rattle snake.jpg|thumb|[[Rattlesnake]]]] | |||
*An average of 5000 native venomous snakebites are reported to US poison centers annually<ref>Seifert SA et al. AAPCC database characterization of native U.S. venomous snake exposures, 2001-2005. Clin Toxicol (Phila). 2009;47: 327–335.</ref> | *An average of 5000 native venomous snakebites are reported to US poison centers annually<ref>Seifert SA et al. AAPCC database characterization of native U.S. venomous snake exposures, 2001-2005. Clin Toxicol (Phila). 2009;47: 327–335.</ref> | ||
*In the United States, snake bites can be organized into [[Crotaline (Pit Vipers)]] and [[Elapidae (Coral Snakes)]] | *In the United States, snake bites can be organized into [[Crotaline (Pit Vipers)]] and [[Elapidae (Coral Snakes)]] | ||
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==Differential Diagnosis== | ==Differential Diagnosis== | ||
{{Bites and stings DDX}} | {{Bites and stings DDX}} | ||
==Evaluation== | ==Evaluation== | ||
Revision as of 04:34, 1 January 2017
Background
- An average of 5000 native venomous snakebites are reported to US poison centers annually[1]
- In the United States, snake bites can be organized into Crotaline (Pit Vipers) and Elapidae (Coral Snakes)
- Crotalidae family also includes rattlesnakes, Sistrurus and Agkistrodon species (water moccasins and copperheads).[2]
- Risk Factors: "The 'T's" Testosterone, Tequila, Tshirt, Tattoos, Toothless, Teasing, Trailer park, Truck
Venom
- Snake venom is a mixture of proteins, peptides, lipids, and metal ions.
- Many bites can be "dry bites" where not venom is released, about ~1/4
Clinical Features
- Local injury - punctures marks from fangs not always visible, erythema, and edema
- Ooze at fang mark reliable sign of envenomation
- Nausea/vomiting
Differential Diagnosis
Envenomations, bites and stings
- Hymenoptera stings (bees, wasps, ants)
- Mammalian bites
- Closed fist infection (Fight bite)
- Dog bite
- Marine toxins and envenomations
- Toxins (ciguatera, neurotoxic shellfish poisoning, paralytic shellfish poisoning, scombroid, tetrodotoxin
- Stingers (stingray injury)
- Venomous fish (catfish, zebrafish, scorpion fish, stonefish, cone shells, lionfish, sea urchins)
- Nematocysts (coral reef, fire coral, box jellyfish, sea wasp, portuguese man-of-war, sea anemones)
- Phylum porifera (sponges)
- Bites (alligator/crocodile, octopus, shark)
- Scorpion envenomation
- Reptile envenomation
- Spider bites
Evaluation
- Clinical Diagnosis
Management
- Treatment mainly depends upon the presence of an envenomation
- Indications:
- Progression of local injury - pain, swelling, ecchymosis
- Coagulopathy - elevated PT/PTT/INR, low fibrinogen, thrombocytopenia
- Systemic effects - hypotension, altered mental status, nausea and vomiting, paresthesias
- Always provide supportive care and treat local effects of any wounds
- Irrigation of the wound is necessary regardless of the type of snake bite
- Debridement and removal of devitalized tissue may be necessary for severe bites
- Snake specific treatments depend upon Coral snake or Pit viper envenomations
Disposition
- All snake bites with evidence of envenomations should have a period of observation and possible hospitalization
- Old bites can be assessed an discharged if no evidence of envenomation.