Venomous Land and Marine Animals, Poisonous Plants and Heat Stroke

SNAKES

• 9000 snake bites annually, with 1% mortality – highest in young children
• DO: remove constricting clothing, transport to hospital immediately, establish IV access, immobilize and raise limb, and mark the leading edge of erythema/edema
• DO NOT: incise the wound, use a venom suctioning kit, apply tourniquets, or apply ice or heat
• In addition to the localized effect of pain from a bite, systemic events include hematologic and neurologic problems.
  • Cellulitis  and compartment syndrome are rare
  • Pain control with opiates
  • Give tetanus if not up to date
• Venomous snakes in the US are either Crotalidae (“pit vipers”) or Elapidae (coral snakes).
  • Crotalids, aka pit vipers, include rattlesnakes, copperheads, and cottonmouths
    • Venomous crotalids have broad heads, elliptical pupils, pointy snouts, and heat-sensing pits on their face
    • More common to have hematologic effects
    • Can use Crofab antivenom for moderate to severe bites (use grading system)
  • Coral snakes are found in the southeastern US
    • “red on yellow kill a fellow” (these are venomous!)
    • “red on black venom lack” (not so much)
• Call the Poison center and your local zoo or snake center (in NYC this is Jacobi Hospital)

SCORPIONS

• Bark Scorpion in the Southwestern US and Mexico is venomous
• Effects:Local injury / pain, cranial nerve dysfunction, neuromuscular hyperactivity, dysautonomia, and rarely pancreatitis or rhabdomyolysis
• 20,000 bites per year, most lethal in children
• Antivenom was discontinued but now made by Mexico, however your best bet is supportive intensive care (intubation, benzodiazepines, etc)

Check out another of our blog posts on scorpions: Bored Review in the Sonoran

• Bites
  • Blue-Ringed Octopus – tiny but deadly, uses tetrodotoxin
  • Sea Snakes – 50 species: all are venomous, 7 are fatal.
• Nematocysts (Jellyfish and Portugese Man o’ War
  • Use barb, spine, and thread to discharge into skin
  • Management
    • Remove nematocysts (shaving cream and credit card method) or warm saline water
    • Consider oral antihistamines and oral corticosteroids
• Stings
  • Sea urchin, sea cucumber and starfish – no venom but cause local irritation
  • Stingrays – cause laceration and puncture envenomation – treat both!
    • Severe local pain
    • Syncope, weakness, nausea, vomiting, diarrhea, muscle fasciculations
    • Treatment: salt water immersion / irrigation, remove stinger, explore wound
  • Bony Fish – have spines with venom
    • Scorpionfish, lionfish, stonefish, catfish
    • Check out our own wilderness medicine post about scorpionfish envenomation
• Ciguatera Poisoning
  • From large fish that eat smaller reef fish that feed off of coral that hosts bacteria
  • Heat stabile, water soluble = you can’t cook it off
  • Clinical manifestations are:
    • GI (3-6 hours) – vomiting, diarrhea, abdominal pain
    • Neurologic (3-72 hours) – paresthesias, tooth discomfort, blurred vision *these can lasts for weeks!
    • Cardiovascular (hours) – bradycardia, heart block, hypotension
  • Treatment is supportive care, mannitol for very severe symptoms
• Scromboid Poisoning
  • From dark meat, large fish (tuna, mackerel, swordfish, mahi-mahi)
  • Caused by bacterial overgrowth when fish is improperly stored (> 40° C) leading to production of histadine (converted to histamine)
  • Clinical manifestations are flushing, rash, diarrhea, headache, numbness (think histamine reaction)
  • Treatment is antihistamines and supportive care, most cases resolve within 12-48 hours
• Pufferfish Poisoning – Tetrodotoxin
  • Not just pufferfish! Also found in frogs, salamanders, octopus, and crab eggs
  • Sodium cannel blockade leads to weakness, hypotension, paralysis and ultimately respiratory failure
  • Treatment is aggressive supportive care and GI decontamination

Lastly, check out this TOKC post reviewing fish-related poisoning.

• Most poisonous plant exposures are unintentional, small, asymptomatic, and from household plants
• Get a thorough history including travel, time of exposure, quantity eaten and which part of plant
• Problems for medical providers include misidentification, scant literature, and variable xenobiotics within a plant. Best bet is to observe your patient!
• Types of Xenobiotics in plants, with examples
  • Alkaloids
    • Jimsonweed – anticholinergic toxicity through atropine
  • Gylcosides
    • Yellow oleander and foxglove – acts like digoxin toxicity
    • Cassava (from improperly prepared yucca) is cyanogenic
  • Terpenes and resins
    • Castor bean – one seed is toxic
    • Causes multi-organ dysfunction – use aggressive decontamination
  • Proteins, peptides and lectins
    • Ackee (official fruit of Jamaica) is toxic when not ripe, causes “Jamaican Vomiting Sickness” manifesting with severe hypoglycemia, vomiting, and seizures.
  • Phenols and phenylpropanoids
    • Capsaicin = pepper spray
• Water Hemlock = most common cause of plant-related (ingestion) fatalities in the US
  • Cicutoxin, found in all parts of the plant
  • Cholinergic manifestations = vomiting, flushing, salivation, bradycardia, hypotension, seizures, and rhabdomyolysis

• Definition = core temperature > 106° F with neurological dysfucntion
• Exertional heat stroke – can be rapid, caused by sports/ athletics in the heat. You may see sweating!
• Nonexertional heat stroke – most common in infants or children left in hot cars and elderly
• Treatment
  • Cooling! Use evaporative cooling as cold water immersion can cause vasoconstriction making cooling more difficult.
  • Treat shivering with benzodiazapines +/- paralytics
  • Antipyretics (acetaminophen) not helpful
  • Mortality from electrolyte imbalance, cardiac arrhythmias, and multi-organ dysfunction
  • In pediatrics, must consider child abuse!