Bites and stings Flashcards
When should antivenom be given for snakebites?
- Signs of systemic envenomation
- Signs of local envenomation that are rapidly spreading
What are the signs of systemic envomenation in snake bite?
Systemic envenomation
* Local swelling, brusing, blistering
* Inocagulable blood (20 min clotting test) or spontaneous bleeding
* Shock/hypotension
* Arrhthmias
* Descending paralysis (ptosis)
* Rhabdomyolisis
* Acute kidney injury
What are clinical features of scorpion bites?
Scorpion bites
* Extremely painful
* Symptoms due to release of neurotransmitters
* Initially Acetylcholine -> nausea, vomiting, seating, salvation, bradycardia
* Follow by Catecholamines -> hypertension, tachycardia, pulmonary edema, ECG changes
What is the management for scorpion bites
- Pain management (opioids, nerve blocks)
- Antivenoms available
- Prazosin if required for hypertension, pulmonary edema, LV failure
What are the common dangerous spiders, their locations, and typical symptomatology?
Black/brown widows - Latrodectus
* Americas, Africa, Sth Europe
* Neurotoxic
Wandering/armed/banana spiders - Phoneutria
* Latin America
* Neurotoxic
Funnel web spiders - Atrax & Hadronyche
* Australia
* Neurotoxic
Brown recluse - Loxosceles
* Americas
* Necrotic
What are symptoms of neurotoxic envenoming from a spider bite?
Neurotoxic (Latrodectus [Widows], Phoneutria [Wandering/Armed/Banana], Atrax [Funnel Web])
* Fever
* Nausea/Vomiting
* Sweating
* Salivation
* Goosebumps
* Muscle spasms
What are signs of necrotic envenoming in spider bites?
Necrotic (Loxosceles [Brown Recluse])
* Fever
* Scarlatiniform rash
* Haemoglobinuria
* Coagulopathy
* Acute Kidney injury
What is the management for spider bite envenoming?
- Mostly symptomatic with pain relief
- Antivenoms are available
What are clinical features/clues to fish stings (e.g. stone fish)
- Usually walking and step on something
- Immediate excruciating pain
- Local swelling and inflamation
- May rarely have more systemic effects
What’s the treatment for stinging fish?
- Immerse affected area in hot (<45 C) water
- Good wound cleaning to prevent infection (e.g. Vibrio vulnificus can be fatal)
- Antivenom for stone fish is available in Australia
In an area of a jellyfish sting, what does rubbing the area of the sting do?
Many of the nematocysts remain undischarged on tentacles that adhere to the victim and rubbing the area of the sting causes fur- ther discharge and worsens envenoming
What is an effective treatment for box jellyfish stings?
Pouring vinegar can prevent further discharge of nematocysts
What is the treatment for Irukandji syndrome?
IV magnesium assists with pain and hypertension
What is the initial first aid treatment for non-box jellyfish stings?
- Seawater should be poured over the stings
- Adherent tentacles gently removed.
