Stings And Bites Flashcards
What is the venoms of bees and wasps
Hymenoptera
What is Hymenoptera from and what is it made from
Bees and wasps
Made of histamine
Melittin: degranualtes basophils and mast cells
Phospholipase and hyaluronidase
What is the most common response to Hymenoptera
The most common response to a Hymenoptera sting is a transient local reaction.
—Localized itching, pain, erythema, and swelling are common.
Getting stung in the eye by a bee or wasp can lead to what complications
Eye lid swelling
Anterior capsule cataract
Atrophy of the iris
Lens abcess
Globe perforation
Glaucoma
Refractive changes
If a pt presents with involuntary muscle spasm and edema without urticaria
Think what?
Bee or wasp sting - Hymenoptera
What is the typical onset of fatality iwth a wasp or bee sting
Within the 1st hour
In general, the shorter the interval between the sting and the onset of symptoms, the more severe is the reaction!!
What is the general non anaphylactic treatment for Hymenoptera
(wasp/bee stings)
removal of the stinger by any means
Wash the site
Cold compress may help
Oral analgesics, nsaids, and antihistamines
Elevate the limb as necessary to reduce edema
Corticosteroids are controversial but are still used
What is the treatment for Hymenoptera (bee stings) anaphylaxis
ABCs 1st
Im Epi 0.3-0.5 1:1000
Aggressive fluids with crystaloids
Anithistamines 1 and 2
+/- steroids
D/c with steroids, antihistamines, and epi pens
Describe a brown recluse
A pigmented, violin-shaped pattern on the cephalothorax
What is the venom from a brown recluse
The venom of the brown recluse contains multiple enzymes, including hyaluronidase and sphingomyelinase D, which is the major enzyme responsible for necrosis!!
Are brown recluse bites painful?
No
What is the red white and blue sign of a brown recluse bite
By day 3 or 4, the hemorrhagic area may become ecchymotic, which leads to the “red, white, and blue” sign
(erythema, blanching, and ecchymosis)
»The ecchymosis becomes necrotic, with eschar formation»Significant cosmetic defect requiring skin grafting.
What is the treatment for a brown recluse bite
Supportive
ABX if signs of infection
+/- dapsone and surgical incision
What si the f/u for a brown recluse bite
Surgical debridement should be delayed until clear margins are established, often 2 to 3 weeks after the bite. (Not in ED!)
Patients with systemic symptoms following a bite warrant hospitalization.
(hypotension, hypertension, sepsis)
What is the scientific name for a brown recluse
Loxosceles reclusa
Describe a Black widows spider
Black with a orange red hourglass
What is the scientifc name for a black widow
latrodectus
What is the most active component of the black widow venom
highly potent venom with the most active component of the venom is
α-latrotoxin
What is the effect of alpha latrotoxin
Acts through both calcium-dependent and calcium-independent pathways leading to receptor stimulation, pore formation, and ultimately massive release of neurotransmitters (predominantly acetylcholine and norepinephrine)
Acetylcholine release accounts for neuromuscular manifestations, and norepinephrine release accounts for the cardiovascular manifestations.
A black widow bites painful ?
Yes
A pt presents with a painful spider bite after cleaning out his wood shed
He know has severe abdominal pain and cramping with HTN and TachyHR
HA, N/V, diaphorsis and photophobia
Think
Latrodectus - black widow
What is the tx appraoch to latrodectus -black widow bites
Supportive measures
+/- IV calcium
Opiods for pain
Benzos for spans
Anti venom
What is the pathophys of a scorpion sting
Most stings cause localized pain at the bite site and can open neuronal sodium channels that cause prolonged and excessive depolarization.
What are the s/s of a scorpion sting
restlessness or uncontrollable jerking of the extremities that appears to be seizure-like activity
Tachycardia, HTN , Pulm edema, and cardio shock
AbnNML oculomotor function
Loss of pharyngeal control uncoordinated RR
Tongue fasciulations
Hypersalivation is common and can threaten the airway
What cranial nerves are effected by scorpion stings
Trigeminal (cranial nerve V)
Facial (cranial nerve VII) Glossopharyngeal (cranial nerve IX)
If a scorpion sting presents with Tachycardia, HTN, and mydriasis
What is the tx
Antivenmon and prazosin
If a scorpion sting presents with pulm edema, what is the tx option
Antivenmo
Nitro or prazosin
Dobutamine
If a scorpion bite presents with HOTN, bradyHR, salivation, sweating, ab pain, and pancreatitis
What is the tx ?
Atropine
When should you admit a scorpion sting
Patients with mild, local reaction without systemic reactions may be discharged home with pain control, return precautions and close follow up.
Patients with systemic symptoms or cranial nerve impairments may need to be admitted.
What is the effect of crotalinae snake venom
Complex enzyme mixture that causes local tissue injury, systemic vascular damage, hemolysis, fibrinolysis, and neuromuscular dysfunction, resulting in a mixture of local and systemic effects.
Crotaline venom quickly alters blood vessel permeability; this leads to loss of plasma and blood into the surrounding tissue, which causes hypovolemia.
Crotaline venom activates and consumes fibrinogen and platelets, causing a coagulopathy.
How does Crotalinae Snake venom effect cranial nerves
In some species, specific venom fractions block neuromuscular transmission, which leads to cranial nerve weakness (e.g., ptosis), respiratory failure, and altered sensorium. (GCS what?!)
What are the early S/s or crotalinae snake bites
early symptoms and signs are nausea and vomiting, weakness, oral numbness or tingling of the tongue and mouth, dizziness, and muscle fasciculation.
What are the systemic effects of crotalinae snake venom
Systemic effects include tachypnea, tachycardia, hypotension, and altered level of consciousness.
In general, local swelling at the bite site becomes apparent within 15 to 30 minutes. (Wicked fast!)
What are the three possible manifestations of a snake bite
Local injury
Hematology abNML
Systemic effects
The absence of any of these manifestations for a period of 8 to 12 hours following the bite indicates a dry bite.
What is the Tx appraoch to crotalinae snake bites
Antivenom
Crotalidae Polyvalent Immune Fab (Ovine) (FabAV)
Establish initial control with 4-6 vials and repeat if not met goal
If goal of control met
Then induce 2-vials at 6-12-18hrs
Measure for anaphylaxis before, during and after admin of anti venom
Measure limb circumference for compartment syndrome q 30 min
Repeat labs q 4 hours
Pt may need fluids and or blood or blood products
What is the F/u for a crotalinae snake bite
Observe for 6-8 hours in the ed
Can discharge if dry bite without s.s at 8 hours
Admit if life threatening S/s or receiving anti venom (general ward)
Describe Elapid snake bites
“Red on yellow, kill a fellow; red on black, venom lack.”
Coral snakes
What is the treatment for Elapid Coral Snake bites
Coral snake venom is primarily composed of neurotoxic components- no local injury.
Admit potential victims of coral snakebite to the hospital for observation, because venom effects may develop hours after a bite and are not easily reversed.
Administer three to five vials of antivenom, Antivenin® (M. fulvius), IV to patients who have definitely been bitten, because it may not be possible to prevent further effects or reverse effects once they develop.
Additional doses of coral snake antivenom are reserved for cases in which symptoms or signs of coral snake envenomation appear.
