Snake bites: Difference between revisions

No edit summary
 
(32 intermediate revisions by 11 users not shown)
Line 1: Line 1:
==Overview==
==Background==
In the United States, snake bites can be organized into [[Crotaline (Pit Vipers)]] and [[Elapidae (Coral Snakes)]].  Although somewhat simplified, the Crotalidae family also includes rattlesnakes, Sistrurus and Agkistrodon species (water moccasins and copperheads).<ref>Goldfranks Toxicology - Envenomations</ref>
[[File:Coral 009.jpg|thumb|[[Coral snake]]]]
[[File:Rattle snake.jpg|thumb|[[Rattlesnake]]]]


==Diagnosis==
*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>
*Clinical Diagnosis
*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).<ref>Goldfranks Toxicology - Envenomations</ref>
*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 no venom is released, about ~1/4


[[File:Coral 009.jpg|thumb|[[Coral snake]]]]
==Clinical Features==
[[File:Rattle snake.jpg|thumb|[[Rattlesnake]]]]
*Local injury - punctures marks from fangs not always visible; erythema, and edema
*Ooze at fang mark reliable sign of envenomation
*[[Nausea/vomiting]]


==Differential Diagnosis==
==Differential Diagnosis==
{{Bites and stings DDX}}
{{Bites and stings DDX}}
==Evaluation==
*Clinical Diagnosis
*Evaluate for [[compartment syndrome]] (see below)
*CBC, coags: [[Thrombocytopenia]] and elevated INR can occur in Crotaline envenomations.
==Management==
{{Snake bite local treatment}}
===Supportive care===
*[[IVF]] and [[pressors]] if needed for [[hypotension]]
*[[pRBCs|Blood]] components rarely needed
*Treatment mainly depends upon the presence of an [[Envenomation|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
*Evidence does not support use of empiric [[antibiotics]] to prevent secondary infection <ref>Gold B.. Bites of venomous snakes. N Engl J Med. 2002;347(5):347-56.</ref>
*[[Compartment syndrome]] has been documented with crotaline envenomation, but current literature does not support use of fasciotomy. <ref> Cumpston KL. Is there a role for fasciotomy in Crotalinae envenomations in North America? PMID: 21740134 </ref> Treatment should focus on antivenom.
===Antivenom===
*Snake specific treatments depend upon [[Coral snake]] or [[Crotaline (Pit Vipers)|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 and discharged if no evidence of envenomation.


==See Also==
==See Also==
*[[Envenomations, bites and stings]]
*[[Crotaline (Pit Vipers)]]
*[[Crotaline (Pit Vipers)]]
*[[Elapidae (Coral Snakes)]]
*[[Elapidae (Coral Snakes)]]


==Source==
==References==
<references/>
<references/>
[[Category:Environ]]
 
[[Category:Tox]]
[[Category:Environmental]]
[[Category:Toxicology]]

Latest revision as of 17:08, 17 March 2021

Background

Coral snake
Rattlesnake
  • 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 no 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

Evaluation

Management

Local Care

  • Do:
    • Remove all jewelry
    • Mark the leading edge of erythema/edema
  • Do not:
    • Attempt to suck out the venom
    • Place the affected part in cold water
    • Use a tourniquet or wrap
    • Antivenom is first line treatment for compartment syndrome; fasciotomy is last resort if elevated pressures persist.

Supportive care

  • IVF and pressors if needed for hypotension
  • Blood components rarely needed
  • Treatment mainly depends upon the presence of an envenomation
  • Indications:
  • 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
  • Evidence does not support use of empiric antibiotics to prevent secondary infection [3]
  • Compartment syndrome has been documented with crotaline envenomation, but current literature does not support use of fasciotomy. [4] Treatment should focus on antivenom.

Antivenom

Disposition

  • All snake bites with evidence of envenomations should have a period of observation and possible hospitalization
  • Old bites can be assessed and discharged if no evidence of envenomation.

See Also

References

  1. ↑ Seifert SA et al. AAPCC database characterization of native U.S. venomous snake exposures, 2001-2005. Clin Toxicol (Phila). 2009;47: 327–335.
  2. ↑ Goldfranks Toxicology - Envenomations
  3. ↑ Gold B.. Bites of venomous snakes. N Engl J Med. 2002;347(5):347-56.
  4. ↑ Cumpston KL. Is there a role for fasciotomy in Crotalinae envenomations in North America? PMID: 21740134
Retrieved from "https://www.wikem.org/w/index.php?title=Snake_bites&oldid=300729"