Alligator and crocodile attacks

Background

Reptilian Order Crocodylia Families

American Alligator

Crocodile

• Alligatoridae (8 species, including alligators and caimans)
• Crocodylidae (14 species, including the true crocodiles)
• Gavialidae (1 species, the Indian gharial).

Epidemiology

• Worldwide there were 1237 attacks and 674 fatalities between January 2008 and July 2013
• In the US there were 567 adverse encounters and 24 deaths between 1928 and 2009 although these events are suspected to be under reported.
  • Most fatalities are reported in Florida, followed by Texas, Georgia, and South Carolina.

Clinical Features

• Usually sudden attacks that catch the human by surprise.
• Can produce large crush injuries, punctures, and lacerations.
• Delayed presentations can have polymicrobial infections, which can cause serious deformity, sepsis, and even death.

Differential Diagnosis

Marine toxins, envenomations, and bites

• Toxins
  • Ciguatera
  • Scombroid
  • Tetrodotoxin (e.g. pufferfish)
  • Shellfish poisoning
    • Amnesic shellfish poisoning
    • Diarrheal shellfish poisoning
    • Neurotoxic shellfish poisoning
    • Paralytic shellfish poisoning
• Stingers
  • Stingray injury
• Venomous fish
  • Cone shell
  • Lionfish
  • Sea urchins
  • Crown-of-Thorns Starfish
  • Stonefish
  • Other: Catfish, zebrafish, scorpion fish
• Nematocysts
  • Coral reef
  • Fire coral
  • Jellyfish (Cnidaria)
    • Box jellyfish
      • Irukandji syndrome
    • Sea wasp
  • Portuguese man-of-war
  • Sea anemones
  • Seabather's eruption
• Phylum porifera (sponges)
• Bites
  • Alligator and crocodile attacks
  • Octopus bite
  • Shark bite
• Infections
  • Vibrio species in saltwater
  • Aeromonas species in freshwater

Evaluation

• Examine patient head to toe for other injuries
• Radiographs to assess for underlying fractures or tooth fragments

Management

• ABCs
• Analgesia and/or regional anesthesia

Wound Care

• Hemostasis
• Aggressive debridement and irrigation
• Injuries close to a joint should be considered open until proved otherwise, with orthopedic consultation for possible exploration and cleansing.
• Areas of concern for compartment syndrome, with associated symptoms and signs of increased pain, tense compartments, and decreased circulation or temperature, should be evaluated with tissue manometry.
• After exploration, irrigation, and debridement, bite wounds should preferably be left open because they are typically crush wounds or deep lacerations with significant bacterial contamination and surrounding soft tissue trauma. Cosmetically sensitive areas should be copiously irrigated and referred for delayed closure after 5 days of antibiotic therapy.

Empirical antibiotic coverage

• First line: fluoroquinolone or third-generation cephalosporin
• Second line: trimethoprim-sulfamethoxazole or carbapenem
• In wounds presenting with hemorrhagic bullae or necrosis, Vibrio species should be considered and the wound treated with surgical drainage and doxycycline, fluoroquinolone, carbapenem, or other appropriate antibiotic.

Disposition

• Patients with cellulitis or signs of sepsis should be admitted to the hospital and treated aggressively.
• Patients with severe trauma should be admitted for further evaluation and management. Only minor wounds and patients with comprehensive plans for follow-up should be managed on an outpatient basis.
• Injuries causing significant trauma to the hands, face, and genitalia may require specialty surgical consultation.

See Also

• Mammalian Bites
• Tetanus Prophylaxis

References

• Constance, Benjamin B and Read, Mark A. "Ch. 33 Alligator and Crocodile Attacks." In Auerbach, Paul S.; Cushing, Tracy A.; Harris, N. Stuart. Auerbach's Wilderness Medicine (7th ed.).Philadelphia: Elsevier, Inc. pp. 687-692.e1