Bites, stings, Envenomation Flashcards
1
Q
- crush injury (tearing injury more common than puncture wounds)
- significant lacerations
- upper extremity, head and neck bites
A
Dog bites
2
Q
- puncture wounds, upper extremity
- upwards 50% infection rate
- higher rate of deep tissue infections
A
Cat bites
3
Q
Human bites pose a significant risk of infection, what pathogens are involved?
A
- strep viridans, or staph aureus
- bacteroides, peptostreptococcus
- boards: Eikenella corrodens
- fight bite often associated with boxer’s fracture
- tx: Augmentin or fluoroquinolone + clindamyacin
4
Q
- Transmission via animal saliva, contact with bites, scratches, abrasions or mucous membranes
- high risk: bats, dogs (abroad)
- no risk: rodents, rabbits, squirrels
- virus ascends peripheral nerves leading to progressive, irreversible ecephalopathy
- sxs: insomnia, confusion, agitation, hypersalivation, hydrophobia
A
rabies
5
Q
prevention of rabies
A
Two part post-exposoure prophylaxis
- RIG: antibody, given one in proximity to bite itself
- HDVC: vaccine, give on days 0,3,7,14
6
Q
what are arthropod threats?
A
hymenoptera
- wasps
- bees
- ants
Arachnids
- brown recluse
- black widows
- ticks
7
Q
management of hymeopetra stings
A
remove stinger (if bee) by scraping, blunt any ongoing envenomation
- localized: edema, pain, redness (ice, antihistamines, single dose corticosteroids)
- mild-moderate: diffuse/disseminated urticaria, pruritis ( IV antihistamines, steroids, monitoring)
- severe to life-threatening: wheezing, angioedema, nausea/vomiting, hypotension, stridor, shock (epinephrine, IV antihistamines, steroids, intubation)
8
Q
Release of chemical mediators
- immune cells leading to a systemic multi-organ reaction
Symptoms
- wheezing, stridor, chest tightness, abdominal pain, diarrhea, hypotension, altered mental sstatus, urticaria, edema
Common antigens
- foods: particularly nuts, shellfish
- insect stings
- medications (particularly antibiotics)
A
anaphylaxis
9
Q
treatment of anaphylaxis
A
- Epinephrine
- steroid
- H1-receptor antihisstamine
- H2- receptor antihistamine
- +/- albuterol for bronchospasm that persists despite epi
10
Q
- Typically nests outdoors and bites when provoked
- local reaction: cytotoxic venom, bites results in a necrotic wound
- systemic reaction: fevers, malaise, hemolysis, DIC
- no clear treatment protocol
- there is an anti-venom, but must be administered within 12 hours of bite
A
Brown recluse
11
Q
- Only females bite, very aggressive when protecting eggs
- local reaction: classically target lesion noted at site of bite (delayed)
- systemic reaction: latrotoxin causes norepinephrine and acetylcholine release, resulting in muscle spasm, cramping
A
Black widow (neurotoxic)
12
Q
- Pain control
- benzodiaepines or calcium gluconate for spasm control
- significant mortality rate in young children
- latrodectus antivenom (treat 1 vial once, no re-dosing)
A
spider bite + acute abdomen
13
Q
- tickborne illness in general in the US
- illnesses (a few of the many)
- spirochetes: lyme disease
- viruses: colorado tick fever, powassen, bourbon virus
- rickettsiae: rocky mountain spotted fever
- bacteria: tularemia, anaplasmosis
- parasites: babesiosis
- alpha gal (induced meat allergy)
A
Ticks (tick borne illnesses)
14
Q
- majority of bites are extremities
- 20% bites are dry bites
symptoms:
initial: intense pain, erythema, and edema
* perioral numbness pluse/minus metallic taste
* nausea/vomiting, chills, weakness, syncope, sweating
4-24hrs
- neuromuscular symptoms
- progressive edema at wound and beyond
- distrubutive shock (may be immediate)
after 24hrs
- observe for compartment syndrome and necrotic tissue
- also, secondary wound infection
A
(Pit Vipers)
15
Q
- antivenom that replaced previous horse serum
- ideal if used within 4 hrs of bite
- initial dose is 4-6 vials (not weight based)
- repeat initial dose if there is progression of symptoms
- once there is no progression, then 2 vials q6hrs for 3 doses
A
utility of CroFab
