Environmental Emergencies Flashcards
1
Q
Pathophys of hypothermia?
A
increased HR, vasoconstriction and increased myocardial oxygen used
hypoventilation with CO2 retention –> hypoxia
decreased mucocillary clearance
slowed mentation, motor func.
decreased platelet func.
2
Q
In hypothermia, there is a shift of oxyhemoglobin curve to the…
A
left
3
Q
When does after drop occur in hypothermia?
A
when cold, acidotic peripheral blood returns to the central circulation
-reason for initial decreased in temp once begin tx
4
Q
After drop can increased the risk for…
A
cardiac arrhythmias
5
Q
At what temp do we loose our shivering ability? what temp is there an increase in arrhythmias?
A
90 deg F
<86 deg F : Osborn J wave
6
Q
We should withhold cardiac meds and defibrillation until temp is…
A
> 82.4 deg F (>28 deg C)
7
Q
If you have an Osborn J wave in V3 and V4 on EKG, you should suspect…
A
hypothermia
8
Q
Tx for hypothermia?
A
warmed O2 and IV fluids
active external rewarming- warm blankets
gently circulating water
active core rewarming
9
Q
If a pt with hypothermia has an arrhythmia then you need to…
A
rewarm pleura w/ active core rewarming
10
Q
What is considered hypothermia?
A
<95 deg F
11
Q
Classification of hypothermia?
A
Mild: 89.6-95°F (32-35°C)
Moderate: 86-89.6°F (30-32°C)
Severe:<86°F (<30°C)
12
Q
Rate of heat transfer with conduction is dependent on…
A
temperature gradient and size of contact area.
13
Q
What are the different methods of heat loss?
A
Conduction, Convection, Radiation, Evaporation
14
Q
Conduction heat loss?
A
transfer of heat by direct contact (water immersion)
15
Q
Convection heat loss?
A
transfer of heat by movement of heated material (wind disrupting heat around body)
16
Q
Radiation Heat loss?
A
uses electromagnetic transmission
17
Q
Evaporation heat loss?
A
conversion of liquid to vapor – usually accounts for 10-15% of body heat loss
18
Q
Pathophys of frost bite?
A
cold exposure > formation of EC ice crystal which damage cell membrane and their osmotic gradient > IC dehydration > IC ice crystal formation > cell death
19
Q
1st deg frost bite?
A
First Degree: anesthetic central white plaque with peripheral erythema
20
Q
2nd deg frost bite?
A
clear or milky-filled blisters surrounded by erythema and edema
21
Q
3rd deg frost bite?
A
hemorrhagic blisters that progress to a hard black eschar
Don’t drain
22
Q
4th deg frost bite?
A
complete necrosis and tissue loss
23
Q
Tx for frostbite?
A
elevate and splint extremity
wrap in sterile gauze, debride white/clr blisters
cover with aloe vera
update Tetanus
Analgesics
smoking cessation
24
Q
Do abx help with frostbite?
A
NO
25
How do ASA and NSAIDs help with frost bite?
decrease thromboxane A2 activity
26
What is keratitis?
inflammation of the anterior chamber of the eye
27
When can ultraviolet keratitis occur?
corneal burn
w/in 1 hr of exposure
does not become sxs until 6-12 hrs later
28
Sxs of ultraviolet keratitis?
severe pain, FB sensation, tearing, conjunctival injection
29
Tx of ultraviolet keratitis?
self limited, analgesics, cold compress, polarized sunglasses
30
Pts at risk for heat exposure?
Age extremes, confusional states, limited water access, alcoholics, mental illness, chronic diseases
-1/5 of young parents believe it is okay to leave children alone in parked cars
31
When does radiation occur?
when air temp is less than body temp
32
What is hyperthermia?
rise in body temp when heat production exceeds heat loss
ex. working out
33
Fever?
rise of core temp in response to circulating cytokines
34
pathophys of heat injuries?
increased endogenous heat production, decreased heat dispersion, exercise increased MR 20-25x baseline rate
35
Is thirst a good gauge of hydration status?
no
36
What meds can increase heat production?
neuroleptics, hallucinogens, amphetamines, anesthetics, LSD, cocaine
37
What meds inhibit sweating?
Antihistamines
Atropine
Neuroleptics
Antispasmodics
TCAs
-children also have less effective sweat mechanisms
38
How long does acclimatization take in adults? children?
7-10days
14 days
39
What is prickly heat?
heat rash
Acute inflammation of sweat ducts caused by blockage of pores
Pruritic, maculopapular erythematous rash found over clothed areas of body
40
Tx for prickly heat?
antihistamines, supportive care
41
Heat cramps?
Painful involuntary spasmodic contractions
Usually sweat profusely but replace with water only
42
Tx for heat cramps?
rest in cool environment
replace fluids/electrolytes
(fix Mg before K)
43
Heat exhaustion?
Dizzy, weak, malaise, N/V, Headache, myalgias
Syncope, orthostasis, sinus tach, tachypnea
normal mental status
44
Tx for heat exhaustion?
rest, volume and electrolyte replacement
45
Heat stoke?
MC in summer months
Triad = Hyperthermia (> 105°F), CNS dysfunction, Anhydrosis
Seizure, ↓BP, ↑HR, ↑RR
46
Abnormal labs in heat stroke?
↑ed Na and Bun -- ↓ed K, Ca, Phos, Mag (dehydration)
elevated transaminase levels
47
Tx for heat stroke?
IV fluids
diagnostics
reduce temp rapidly: remove clothes: strategic ice packs
TOC= evaporative cooling
Diazepam to inhibit shivering
48
Bad prognostic factors for heat stroke?
Delayed rapid cooling
AST > 1000
DIC
Prolonged coma
Hypotension
Renal failure in first 48 hours
49
Marine Envenomations -Jelly fish?
Pruritic pain, wheals, urticaria
50
Tx for jellyfish envenomation
vinegar to remove nematocyst
topical anesthetics
oral analgesics
no role for abx
51
Sxs of stingray envenomation
pain, bleeding
52
Tx for stingray envenomation?
irrigation, remove foreign debris, hot water immersion
NO abx
53
Catfish envenomation sxs/tx?
similar to stingray
54
Etiology of hypothermia?
Medical illnesses (DM, PVD, ASVD, Neuropathy, Psychiatric illness)
Ethanol (MCC in US)
Wind chill
Clothing (wet vs none)
Smoking
Homeless
MCly affects males 30-49 y/o
55
Hymenoptera Stings, what are the two classes?
Vespids – Yellow Jackets, Hornets, Wasps – sting multiple times
Apids – Honey and bumblebees – barbed stingers
MCC of allergic reaction secondary to insect stings = Yellow jacket
56
What is the MCC of death from envenomation for hymenoptera stings?
upper airway obstruction
57
Nest locations for bugs?
Ground – Yellow jacket
Under leaves or windowsill – Wasps
Bushes, low-lying limbs - Hornets
58
Sxs of Hymenoptera stings?
Local reaction – Pain, erythema, edema, pruritis, swelling
Systemic/anaphylactic rxn: most within 15 minutes:
Itchy eyes, facial flushing, urticaria, dry cough, dyspnea, wheezing, abdominal cramps, n/v/d, fever, arthralgias. IgE mediated histamine release
59
Hymenoptera stings tx?
clean with soap/water, remove stinger
Ice, elevate
antihistamines (Benadryl + type 2 i.e. Pepcid)
epi
steroids
Beta agonists
DC w/ auto injector epi
60
If you give a pt with a rash epi and it goes away...
you know its an allergic rxn
61
Brown Recluse Spider Bites
Loxosceles
MC in Midwestern and southern US
Woodpiles, sheds, garages, closets
light brown/tan
62
Brown Recluse Spider Bites active enzyme? sxs?
Sphingomyelinase D
Mildly erythematous lesion that becomes firm and dry over days to weeks Bluish blister then necrosis
+F/C, N/V, myalgias, petechia, seizure
63
Dx Brown Recluse Spider Bites? Tx?
No specific dx. CBC, BMP, Coags, UA
supportive, surg once clearly demarcated
64
Black Widow Spider Bites
Latrodectus
North America except Alaska
Attics, barns, sheds, garage, firewood, hay bales
Shiny black with red hourglass on abdomen
65
Black Widow Spider Bites pathophys
alpha lactrotoxin
venom releases acetylcholine and norepinephrine at neurosynaptic junction> inhibits their reuptake > muscle contractions and fatigue
66
Hallmark of Black Widow Spider Bites? Other sxs?
muscular cramping
N/V, diaphoresis, hypertension, tachycardia, anxiety, agitation, irritability, weakness, headache, periorbital edema
HTN 10-30%, shock, coma, res failure
67
Tx for Black Widow Spider Bites?
Narcodics, Benzos, Antivenin (horse serum)
Ca Gluconate (but doesn't really help)
68
Describe lice
Intensely pruritic wheals
Waists, shoulders, axillae, neck
Eggs not easily brushed off
69
Tx for lice?
Lindane (avoid in young children and pregnant females)
fine combing of hair
sterilize clothing/bed linens
70
Scabies presentation?
Hands and feet between digits
White zigzag threadlike pattern
very pruritic
71
Tx for scabies?
Elemite or Lindane
Calamine lotion
Oral antipruritic agents (atarax)
Analgesics
72
Snake bites epidemiology?
Rattlesnakes, copperheads, moccasins account for 90-95% of bites
MC time for bites is August to October
Male: Female = 9:1
UE >LE for adults, opposite for kids
73
20-25% Crotaline bites are ...while 60% of coral snakebite are...
dry = no envenomation
74
Which is poisonous, coral snake or king snake?
coral snake
75
Pit viper characteristics?
Pit (heat sensor) between eye and nostril
Elliptical vertically-oriented pupils
Triangular-shaped head
Retractable fangs
76
What does venom do?
Venom causes local tissue injury, systemic vascular damage, hemolysis, fibrinolysis, and consumption of fibrinogen and platelets
77
Cardinal features of snake bites? other sxs?
one or more fang marks, localized pain, erythema, ecchymosis, progressive edema
N/V, weakness, paresthesias of mouth and tongue (metallic taste), tender lymphadenopathy, tachycardia, dizzy, hematuria, decreased platelets
78
Tests for snake bites?
CMC, CMP, Coags, T/S
79
Tx for snake bites?
elevate extremity,
extractor device
constriction bands (occludes venous outflow)
observe for at least 8 hrs
admit all children w/bites
"cut and suck" NOT recommended, NO abx
80
When are antivenins indicated for snake bites?
worsening swelling, coagulation abnormalities (↓ed platelets, PT > 20 seconds), systemic effects (hypotension), all copperhead bites
Rx: Polyvalent Immune Fab
old: Antivenin Crotolidea Polyvalent
81
Scorpion sting pathophys
Venom (neurotoxin) activates sodium channels which causes immediate paresthesias, tachycardia, ↑ secretions, ↑ temperature, diaphoresis, SLUDGE
82
What is pathognomonic for scorpion sting? other common sxs?
roving eye movements
fasciculations, difficultly swallowing
83
Scorpion envenomation grades?
1 – Local pain and/or paresthesias
2 - Pain and/or paresthesias remote from site of sting
3 – CN/autonomic or
somatic dysfunction: blurred vision, roving eye movements, hypersalivation, tongue fasciculations, shaking/jerking
4 – CN/autonomic and somatic nerve dysfuntion
84
Tx for scorpion sting?
Cool compress
+/- midazolam
Anascorp $$$$
-3 vials in 10 mins
85
Tx for cactus spikes?
elmer's glue
local wound care
86
Define drowning
process resulting in primary respiratory impairment from submersion/immersion in a liquid medium
87
Submersion v. immersion?
entire body covered in liquid medium
part (oral and nasal airways) covered in liquid medium
88
Risk factors for drowning?
African Americans (except 0-4 y/o), unsupervised pool/bath time, bath seat use, seizure, alcohol use
89
Pathophys of drowning
percived risk of drowning>
last inhalation effort>
submersion/immersion> (LOC)
tissue hypoxia, acidosis, hypercapnia>
laryngospasm or aspiration>
respiratory failure/death
-surfactant can be washed out, most victims will ingest water
90
What determines prognosis of drown?
duration of submersion/immersion
Good: age <14, CPR in field, CPR <25 mins, detectable pulses on arrival
Poor: submersion >5 mins, no resuscitation for > 10 mins, fixed/dilated pupils, GCS <5, ph < 7.1
91
How long should asxs drowning pts be observed? those who required resuscitation?
4-6 hrs
eval in hospital
92
drowning tx?
o2 if o2 <92%
admit 24 hrs
postural drainage/heimlich -unproven efficacy
93
What are the zones of thermal burns?
Zone of coagulation
Zone of stasis
Zone of hyperemia or inflammation
94
Rule of nines? What is this used for?
```
Head/neck – 9
Each UE – 9 (9x2)
Each thigh – 9 (9x2)
Each lower leg/foot – 9 (9x2)
Clavicle to pubis – 18
Root of neck thru buttocks – 18
Perineum – 1
ROT = back of hand = 1% BSA
```
to determine total body area burned
95
First deg burn
epidermis only – painful, red, no blisters – sunburn
96
Second deg burn
partial: partly thru dermis – blisters, painful – hot liquids
deep: thru hair follicles and sweat glands – hot steam or oil
97
Should you drain blister from second deg burn?
NO
98
Third deg burn
skin to fat – charred, pale, painless, leathery feel
99
What is included in the major burn criteria?
```
Partial thickness > 25% BSA in 10-50yo, > 20% if < 10yo or > 50yo,
Full thickness > 10% in anyone,
Any burn to hands, face, feet, perineum
Any burn crossing major joint,
Circumferential limb burn,
Inhalational or electrical injury,
Burn with fractures,
Burns in infants and elderly
```
100
Tx for burns
update tetanus
NG tube
LR via 2 large bore peripheral IVs
"2-4 in 24, 1/2 in 8 the rest can wait"
keep UO 0.5-1cc/kg/hr for adults
IV narcotics
sharply debride OPEN blisters
cover with sterile moist dressings w/out abx if transferring
If DC, 24 hr FU
101
What is more lethal carbon monoxide or cyanide?
cyanide
CO is more common
102
When should you suspect smoke inhalation?
```
Facial, intraoral, or pharyngeal burns,
Singed nasal hairs,
Soot in mouth or nose,
Hoarseness
Carbonaceous sputum, Wheezing
```
103
CO pathophys
CO binds to hgb --> carboxyhemoglobin
CO has affinity for Hgb 200x that of O2 --> leftward shift of hgb oxygen dissociation curve
104
When should you suspect CO poisoning?
if have multiple family members with nonspecific symptoms, which resolve in the ED
normal CO-Hgb: 2-5%
105
CO-Hgb level and sxs
< 10% = asymptomatic
10-30% = H/A, N/V, Loss of dexterity
30-40% = Confusion, Lethargy, ST segment depression
40-60% = Coma
>60% = Death
106
When is hyperbaric tx for CO indicated?
CO-Hgb >25-30%
Cardiac involvement
Severe acidosis
Transient or prolonged
unconsciousness
Neurological impairment
Age >36 years old
Pregnancy
107
cherry red skin is indicative of?
CO poisoning
108
Etiology of cyanide poisoning?
smoke inhalation, byproduct burning (wool, silk), fruit pits containing amygdalin, cassava root, jewelry and textile industries, sodium nitroprusside
109
cyanide pathophys
Cyanide disrupts mitochondrial production of ATP by binding to and inhibiting cytochrome oxidase --> cessation of aerobic cellular metabolism
110
Cyanide sxs
Mild: HA, N, vertigo, tachypnea, HTN, AMS
severe: dyspnea, bradycardia, hypotension, arrhythmia, LOC, convulsions, CV collapse
111
findings for cyanide poisoning?
severe metabolic acidosis, usually not cyanotic, smells like bitter almonds
112
Cyanide tx
O2, amyl nitrate, sodium nitrite, sodium thiosulfate
113
Acid chemical burns causes...
coagulation necrosis which limits penetration of chemical
114
Alkalis chemical burns cause...
liquefactions necrosis
115
Would you rather get burned by acid or alkalis?
acid
but both suck
116
Therapy for chemical burns?
hydrotherapy
117
In electrical injuries, what is more dangerous alternating current or direct current?
alternating current
118
Pathophys of electrical injuries?
Cell membrane disruption, edema, coagulation necrosis, ischemia, release of myoglobin (renal failure from rhabdomyolysis
AC may precipitate V fib
119
Possible sxs of electrical injuries
cardiopulmonary arrest, LOC, seizure, amnesia, HA, compartment syndrome
120
Electrical burn tx
CBC, CMP, CK =, myoglobins
IV fluids
myoglobinuria
update tetanus
121
What are the dif. ways lightning strike injuries can occur?
direct strike
side flash/side splash
ground current
conduction
streamer
122
MCC of death from lightening injuries? sxs?
asystole
fatality rate 20-30%
res arrest, "stunned" HA, myalgias, paresthesias, temporary LOC, vision & hearing loss-usually gradually resolves
123
fern like rash pattern is pathognomonic for
lightening injuries
124
Lightening injuring dx? Tx?
CBC, CMP, CK, EKG +/- or CT braine
Tx: aggressive fluids not needed
if survive to ER, admit
125
Your neighbor knows you have just completed PA School and comes over to ask you “some medical advice”. He was in the backyard cleaning his storage shed about 45 minutes ago when he was bitten by something. He now complains of severe abdominal pain and nauseous and hypertensive. What most likely bit him?
A. Black widow spider.
B. Brown recluse spider.
C. Granddaddy long leg spider.
D. Scorpion
A
126
```
What treatment do you suggest to him?
A. Scorpion antivenin.
B. Dapsone.
C. Black widow antivenin.
D. Amoxicillin
```
C
127
While climbing Camelback Mountain with your friends, you are bitten by a rattlesnake on the leg. What is the preferred treatment of your injury in the field?
a. Apply tourniquet to the involved extremity.
b. Apply constriction band to the involved extremity.
c. “Cut and Suck” the venom from the wound.
d. Apply warm compresses to the wound
B
128
Your friends transport you to the hospital for further evaluation. While in the ED, you are noticed to have progressive swelling of your leg, hypotension, platelet count of 50K, and a PT of 25 seconds. Should you be given antivenin?
a. Yes.
b. No.
A
129
What is the treatment of choice for an anaphylactic reaction to a bee sting?
Epinephrine
130
What is the pathognomonic physical exam finding in scorpion sting?
Roving eye movements
131
58 year old gentleman presents with hypothermia. Core temperature is 85.5°F. Which of the following is the most accurate?
A. Shivering is common
B. Osborne J wave is pathognomic
C. Rough handling can produce dysrhythmias
D. NG tube should be inserted
C + B
132
```
Patient presents after being bitten while outside. Bite has target area with muscle cramps. What is the most likely cause?
A. Black widow spider
B. Hobo spider
C. Brown recluse spider
D. Tarantula
E. Scorpion
```
A
133
What is the most lethal form of acute mountain illness?
HAPE
134
```
What is the most important treatment option for acute mountain sickness?
A. Oxygen
B. Dexamethasone
C. Hyperbaric therapy
D. Acetazolamide
E. Immediate descent
```
E
