animal envenomations and poisoning

poisonous

having a substance that through its chemical action usually kills, injures or impairs an organism

venomous

having a poisonous substance transmitted to prey or an enemy by biting or stinging

toxic

containing or being a poisonous material, may cause death or other adverse health effect

poisonous/ venomous invertebrates

• cnidaria

• arthropoda

• mollusca

• echinodermata

poisonous/ venomous vertebrates

• pisces

• amphibia

• reptilia

• aves

• mammalia

cnidaria toxins

• jellyfish

• sea anemone

• corals

nematocyst

• stinging mechanism common throughout phylum

• consists of a coiled thread varying in length

• barb on end of thread delivers the toxin to the prey or victim

• 75% as powerful as cobra venom

effect of jellyfish (physalia) sting

• pain

• fever

• shock

• interference with heart and lung action

• death

result of contact from jellyfish

•Residual whip-like, red wavy, stringy welts on the skin from contact with tentacles

•Painful papular-urticarial eruptions.

•Lesions can last for minutes to hours, and the rash may progress to urticaria, hemorrhage, or ulceration.

•Recurrent episodes of urticaria may last four to six weeks at the site of envenomation.

first aid treatment of cnidarians

•Keep patient calm

•Don’t rub with sand or a towel

•Avoid getting stung yourself!

•Inactivate with 5% acetic acid soak for 30 minutes

•Do not use tap water

•Remove adhered tentacles with tweezers or scrap off with a dull knife or credit card

•Transport to a healthcare facility, if needed

mollusca

cone shells (conus)

conotoxin

paralytic poisons from Pacific cone snails

Symptoms of conotoxin

•Burning pain and swelling

•Local numbness, spreading rapidly to involve the entire body (maybe without pain but with some cardiac and respiratory distress at the height of the poisoning)

•Progressive weakness, loss of coordination, drooping eyelids (ptosis), shallow breathing

•Headache, nausea, stomach cramps, shortness of breath

symptoms in fatal cases of conotoxin

•Numbness without pain

•Lips became stiff

•Blurred vision

•Paralysis

•Coma

onset of symptoms of conotoxin

Almost immediate upon injection

octopi venom / cephlatoxin

•A protein-based toxin, found in the salivary glands of cephalopods (octopus)

•Hapalochlaena maculosa & H. lunulata

•Blue-Ringed Octopus

Blue-Ringed Octopus toxin

tetrodotoxin

tetrodotoxin

•Neuromuscular paralyzing venom (neurotoxin) - blocks sodium channels and causes motor paralysis and may cause respiratory failure

symptoms of tetrodotoxin

•Numbness around the mouth followed by lip tingling/paralysis

•Hypotension

•Cyanosis

•Respiratory failure

•Death

treatment of mollusca envenomation

•No antivenom available

•Offer supportive care, including:

• Immobilize patient

•Artificial respiration

•Mechanical ventilation until toxic effects subside (~24 hours at most)

•Wound care

venomous echinodermata/ starfish

•“crown of thorns”

•Acanthaster planci

symptoms of acanthaster planci

•Can cause many deep punctures, GI symptoms, muscle paralysis

acanthaster planci venom

•Treat with hot water

•Pain meds

arthropoda

•Compounds may be applied through bite, sting, or secretion

arthropoda

• fire ants

• brown scorpion

• red wasp

• centipede

hymenoptera

•Account for more deaths in the U.S. than any other envenomation

ants

•sting 9.3 million, others > 1 mill/yr

large local reaction

17-56% of hymenoptera

generalized reaction

1-2% of hymenoptera

seek medical care

5% of hymeoptera

hymeoptera

•Target organs include skin, vascular system and respiratory system

onset of hymenoptera symptoms

50% of deaths occur within 30 min.  75% in 4 hours

LOCAL-

•pain, edema, bleeding, pruritis, vasodilatation, may see N/V

URTICARIA

widespread erythema (whelps) to skin with or without local sx

GENERALIZED

urticaria, wheezing, airway edema, weakness, syncope, anxiety, confusion, hypotension

grades of hymenoptera reactions

• local

• urticaria

• generalized

hymenoptera venome

•Primarily composed of mixture

•Proteins

•Peptides

•Amines

hymenoptera venom

•Toxic component: acetylcholine, histamine, bradykinin, dopamine and serotonin

Diphenhydramine

- limits local response

prehospital treatment of hymenoptera

•Clean wound - remove stinger

•Ice or cool compress – avoid heat

•Elevate extremity – limits edema

fire ant / solenopsis invicta

•Venom is 95% alkaloid – stings develop sterile pustules – leave them intact

Fire Ant Treatment

•Immediate assessment and treatment required for severe reactions –

•Epipen / ER may be indicated

•Diphenhydramine - limits local response

•Clean wound

•Apply baking soda paste

•Ice or cool compress – avoid heat

•Elevate extremity – limits edema

black widow spider

Latrodectus mactans

Brown recluse spider

Loxoseceles reclusa

Male Black Widows

very small and lack the red marking.

Alpha-latrotoxin

causes the toxic effects seen in humans by opening cation channels and causing blockade at neuromuscular junctions

black widow pathphysiology

•Predominant effects are neurological and autonomic

Black Widow History & Presentation

•Bite commonly described as pinch or pinprick, generally trivial

•Systemic symptoms begin within one hour and may last for days

•Muscle cramping begins locally then extends to large muscle groups such as abdomen, back, chest and thighs

•Also see N&V, headache, and anxiety

Black Widow
Physical Findings

•Hypertension, tachycardia, diaphoresis

•Tiny fang marks may be visible with mild local redness at bite site

•Abdominal rigidity may mimic an acute abdomen

•Neurologic effects including weakness, fasciculations & ptosis have been seen

Grade 1 (Mild):

local pain and normal vitals

Grade 2 (Moderate):

•Extension of muscular pain from extremity to trunk; local diaphoresis; normal vitals

Grade 3 (Severe):

Generalized muscular pain to back, abdomen, chest; remote diaphoresis; abnormal vitals(htn & tachycardia); NV and headache

opioid analgesics and benzodiazepines

•Most black widow envenomations managed with

Latrodectus-Specific Antivenin for grade 2 or 3 envenomation

•refractory to opioids and benzodiazepines (1-2 vials)

Calcium gluconate and muscle relaxants

not currently recommended for black widow envenomation

Brown Recluse spider
Loxoseceles reclusa

•Violin shaped marking on back of thorax has led to name “Fiddleback Spider”

Brown Recluse spider
Loxoseceles reclusa

•Varies in size up to 2-3cm. Most active at night from spring to fall

Brown Recluse
Bite

•Envenomation elicits minimal sensation initially and frequently goes unnoticed

Brown Recluse
Bite

•Initial stinging sensation is replaced by severe pain and itching from local vasospasm and tissue ischemia

Brown Recluse

•Edema around the ischemic bite site produces erythematous halo-effect

brown recluse

•Erythematous margin around bite enlarges from gravitational spread of venom into tissues

brown recluse

•Clear or hemorrhagic vesicle classically appears in 24 hours at center of bite

•Vesicle later forms a dark eschar

brown recluse tx

•Local debridement, elevation and loose immobilization are warranted

brown recluse tx

•Local cold compress is helpful since venom is temperature dependent

brown recluse tx

•Monitor for signs of systemic toxicity – hemolysis, renal failure & coagulopathy

Loxoscelism

•a systemic syndrome of coagulopathy, hemolysis renal failure and death is much less common

brown recluse

•Venom is cytotoxic and hemolytic with at least 8 components. 

Sphingomyelinase D

the protein responsible for majority of tissue destruction and hemolysis

brown recluse

•Wound care specialist for larger wounds

•Skin grafting may be necessary after 4 to 6 weeks of standard therapy

•Loss of digits and amputations have been reported

•Use caution when venturing into the habitat of the “Brown Recluse”

Sx of fish toxins

•Intense throbbing pain peaks in 1-2 hours and lasts 12 hours.

•Redness, bruising, swelling, numbness, tingling, and tissue sloughing at the wound site may also occur.

•Severe reactions include nausea, vomiting, abdominal cramps, tremors, abnormal heart rhythms, weakness, shortness of breath, seizures, decreased blood pressure, fainting, and paralysis.

•Death may occur.

Tx for fish venom

•Immerse the wound in water as hot as the victim can tolerate for 30-90 minutes. Repeat as necessary to control pain.

•remove any spines or sheath remaining in the wound.

•Cleanse the wound and then flush the affected area with fresh water

Antivenom is available for stonefish

•Tadpole Madtom (Noturus gyrinus)

•Sting is similar

    to a wasp

puffer fish

•Family: Tetraodontidae

•Deadliest Fish

•2nd most toxic vertebrate

tetrodotoxin

•AKA: puffer or fugu poison

•Found in certain puffer fish

  ocean sunfish and

  porcupine fish

tetrodotoxin

•Onset from 15 minutes to a few hours

•Initially, lip and tongue paresthesia

•facial and extremity paresthesia and numbness

•Salivation, N,V,D, abd pain (severe)

Motor dysfunction with speech difficulties

•Rapidly ascending paralysis over 2-4 hours

•extremity progresses to respiratory

•Finally, cardiac dysfunction, CNS dysfunction, and seizures

•Death usually in 4-6 hours

tetrodotoxin

•Dietary history is key to diagnosis

•AC if early

•Aggressive supportive care

•Airway management

•Antiarrhythmics, pressors

•

•NO ANTIDOTE!

Toads of the family Bufonidae

are the most important of the toxic Anura

chemical composition of toad secretions

•Biogenic amines such as epinephrine, norepinephrine, dopamine and epinine are sometimes found

•Indoalkylamines such as bufotenin, bufotenidin and bufoviridin

toad secretions

cause vasoconstriction, hypotension and hallucinations

bufogenines

•These have a marked effect on smooth muscle including the heart

•Golden Poison Dart Frog

•Phyllobates terribilis

•Most poisonous vertebrate

  in world

Elapidae

cobras, coral snakes, kraits, mambas

Hydrophiidae

true sea snakes

Laticaudidae

sea kraits

Viperidae

old world vipers and adders

Crotalidae

rattlesnakes, copperheads, water moccasins, fer-de-lance, bushmaster, boomslang

rattlesnakes

Almost all deaths due to_____ (of snakebites)

Crotalid toxin activity

•Alterations in the integrity of blood vessels

•Changes in blood cell and coagulation mechanisms

•Alterations in cardiac, nervous systems

reptile toxins

•Hypotension and shock are the major therapeutic problems.

Crotalid Venom Constituents

•Enzymes

•phospholipase A2

•phosphomonoesterases

•endopeptidases

•collagenases

•arginine esterase

•L-amino acid oxidase

•lysophospholipase

•phosphodiesterases

•exopeptidases

•elastases

•hyaluronidase

NAD nucleosidase

Crotalid Venom Constituents

•Amines

•serotonin

•bradykinin

first aid for snakebite

•Do Not Do:

•Incision and suction

•Immersion in ice

•Lymphatic constriction

•Wyeth Crotalid Antivenom:

•Commercially manufactured since 1947 by Wyeth

•Polyvalent horse serum

•Contains IG’s plus other proteins

•Low incidence of Type I hypersensitivity

•High incidence of serum sickness

CroFab®  Antivenom

•Ovine derived antivenom

•Lower incidence of serum sickness

•All N.A. crotalids

Elapids

•are a family of snakes that possess a venom that is primarily neurotoxic in nature

Acetylcholinesterase

catalyzes the hydrolysis of acetylcholine to choline and acetic acid.

gila monster

(Heloderma suspectum

bearded lizard

•(Heloderma horridum)

heloderma

The venom is produced in glands in the lower jaw and transferred through ducts near the base of the larger teeth of the lower jaw