Environmental Emergencies Flashcards
(89 cards)
1
Q
Definition and classification of Hypothermia
A
Def: core temp = 95F
Mild: 89.6-95F (32-35C)
Mod: 86-89.6F (30-32C)
Severe: <86F(<30C)
2
Q
Conduction
A
Transfer of heat by direct contact (water immersion)
3
Q
Convection
A
Transfer of heat by movement of heated material (wind disrupting heat around body)
4
Q
Radiation
A
electromagnetic transmission
5
Q
evaporation
A
conversion of liquid to vapor - usually accounts for 10-15% heat loss (sweat, resp processes)
6
Q
Etiology of hypothermia
A
medical illness (DM, PVD, ASVD, Neuropathy, Psych)
Ethanol (MCC)
wind chill
clothing
smoking
homeless
7
Q
High risk pt for hypothermia and MC
A
age extremes, altered sensorsium
MC: males 30-49 y.o; extremities
8
Q
Pathophys of hypothermia
A
Initially have increased HR, vasoconstrict + incr O2 consumption but decrHR after 32C
Hypoventilation w/ CO2 retention (=hypoxia, rest acid)
Decreased mucocillaiary clearance (incr secretions, dear gag/cough = incr aspiration)
Slowed mentation, motor, speed of reasoning
dear plt fan 2/2 sequester in portal system (= incr blood viscos + thrombi)
Decr. colga factor activity
cold diuresis
imp. insulin release
shift Oxyhemo curve to Left (harder to unload)
9
Q
Hypothermia: what happens after trx started
A
cold, acidotic peripheral blood returns to central circ = temp decr. further and incr. risk for arrhythmia
10
Q
Hypothermia: 3 main priority organs
A
brain, heart, kidney
11
Q
hypothermia: clinical abnormalities
A
shivering stops @ 90 (32.2C)
incr. arrhythmias @ <86(30): Osborn J wave
w/hold card meds and defib until temp >82.4F (28C)
12
Q
Hypothermia: common EKG signs
A
Osborn J-wave; no bunnies in v1/v2, but +in v3
13
Q
Hypothermia: trx
A
warms O2 vent + warmed IV fluids
Active external rewarm (blankets) 1 deg C/hr
Gently circulating water (104-107.6F, 40-42C)
Active core rewarm (incr 2 deg/hr) = 2 cutes tubes each side w/ warm fluid in top, out bottom; warm NGT/urinary catheter + IVF
14
Q
Frostbite Pathophys
A
- Cold Exposure
- Formation of extra cell ice crystals damaging cell membranes and osmotic gradient
- Intracell dehydration
- intracell ice crystal formation
- Cell death
15
Q
Frost bite classifications
A
first deg: anesthetic central white plaque w/ peripheral erythema
2nd deg: clear or milky-filled blisters surrounded by erythema and edema
3rd deg: hemorrhagic blisters that progress to hard black eschar
4th degree: complete necrosis and tissue loss
16
Q
Frostbite Treatment
A
- elevate and splint extremity
- wrap in dry gauze
- debride white/clear blisters
- aloe vera q 6 hr
- tetanus
- analgesics (ASA, NSAIDS, narc)
- Abx no role
- no smoke
17
Q
UV Keratitis
A
-snowstorm/flare on slit lamp
damage to anterior chamber of eye
-develop w/in 1 hr of exposure; no symp until 6-12hrs
-severe pain, foreign body sensation, tearing, conjunctival injections
-bad far vision
18
Q
UV keratitis Trx
A
- self-limited
- analgesics, cold compress
- cyclogel helps spasm
- polarized sunglasses
- patching not recommended
19
Q
Heat Injuryies high risk pt
A
age extremes, confusional states, limited water access, ETOHics, Menta illness, chronic dz
20
Q
Heat injury: when does radiation occur
A
when air temp < body temp
21
Q
What is hyperthermia
A
a rise in body temp when heat production exceeds heat loss –fever is rise of core body temp in response to circulating cytokines
22
Q
Heat Injuries Pathophys
A
-incr endogen heat prod
-decr. heat dispersion
-thirst is poor gauge of hydration status
excerise incr. metabolic rate 20-25x
23
Q
What meds incr. heat production?
A
neuroleptics, hallucinogens, amphetamines, anesthetics, LSD, cocaine
24
Q
What meds inhibit sweating?
A
Antihistamines, Neuroleptics, TCAs, Atropine, Antispasmodics
25
how long does acclimation take?
7-10 for adults, 14 for children
26
Prickly Heat (AKA heat rash)
Acute inflammation of sweat ducts caused by blockage of pores
Pruritic, emaculoppular erythematous rash found over CLOTHED areas of body
Trx: antihistamines, supportive care (cool compress)
27
Heat Cramps
Painful involuntary spasmodic contractions
usually sweat profusely but replace w/ water only (cramping 2/2 lyte deficit K, Mg)
Treated with rest in cool environment, replacement of fluids and lytes
28
Heat Exhaustion
Dizzy, weak, malaise, N/V, H/A, myalgias
Syncope orthostasis (drop in 20 from lying to standing), sinus tach (1st treat based on cause), tachypnea
Normal mental status
Treat: rest, volume, lyte replacement
29
What separates heat exhaustion from heat stroke?
Normal mental status in heat exhaustion; altered in heat stroke
30
Heat Stroke
MC in summer
TRIAD: hyperthermia (>105F), CNS dyxfxn, Anhydrosis
Seizure, decr. BP, incr HR + RR
Labs: incr. Na/BUN, decr. K, Ca, Phos, Mg
Markedly ELEVATED TRANSAMINASE LEVELS
5% renal failure + rhabdo)
25% ARDS
31
Heat Stroke treatment
aggressive hydration (IVF @ 250ml/hr w/ foley - monitor UO)
Diagnostics
Reduce temp rapidly to 104F
Remove clothes and apply strategic ice packs (Axilla, neck, groin)
TOC: EVAP COOLING
Diazepam to inhibit shivering
32
Heat Stroke Poor Prognostic Factors
```
Delayed rapid cooling
AST > 1000
DIC
Prolonged coma
hypotension
Renal Failure in 1st 48 hours
```
33
Jellyfish sting
-Pruritic pain, wheals, urticaria
Vinegar used to remove nematocyst (tails); can also use isopropyl alcohol
Topical anesthetics
Oral analgesiscs
No ABX
34
Stingray or Catfish
Pain, bleed
Irrigation, removal of foreign debris
Hot water immersion (dissolves)
Abx controversial (consider if in dirty water)
35
Vespids
Yellow jackets, hornets, wasps
sting mx times
bad guys
36
Apids
honey and bumble bees
barbed stingers
37
MC allergic rxn 2/2 insect stings
yellow jacket
38
MCC death from envenomation
Upper airway obstructions
39
Nest locations
ground = yellow jacket
under leaves/window: wasps
Brushes/lowlying limbs = hornets
40
Hymenoptera Stings
Local rxn: pain, erythema, edema, pruritus, swelling
Systemic/anaphylactic: majority occur w/in 15 min
-itchy eyes, facial flush, urticaria, dry cough, dyspnea, wheeze, abdominal cramps, N/V/D, Fever, arthralgia
IgE mediated histamine release
Anaphylaxis happens from 2nd exposure
41
Hymenoptera Stings: Trx
```
clean wound w/ soap + H2O, remove stinger
apply ice pack + elevate
Antihistamins
epinephrine
Steroids
Beta Agonists
D/c w/ auto-injector of epi (eli-pen)
```
42
Brown Recluse Spider
Loxosceles
MC in midwest + south
Wood piles, sheds, garages, closets
Light brown to tan w/ dark violin-shaped mark
43
Most active enzyme in Brown Recluse Spider Bite
Sphingomyelinase D
Starts dissolving things in skin. Later leads to necrosis
44
Brown Recluse Spider Bite Si/sx
Mildly erythematous lesion that becomes firm and dry over days-weeks; blush blister then necrosis
F/C, N/V, myalgia, petechia, seizure
45
Brown recluse spider test and trx
Test: CBC, BMP, Coags, UA; no specific is dx
Trx: supportive, sx once clearly demarcated - wait until wound defines itself
No antivenin available; no benefit for steroids, abs, dapsone, early excision, hyperbaric O2, topical NTG
46
Black Widow
Lactrodectus
North America (not Alaska)
Attics, barns, sheds, garage, firewood, hay bales
Shiny black w/ red hourglass on abdomen
47
Black Widow pathophys
Alpha-latrotoxin
Venom releases acetylcholine and norepinephrine @ neurosynaptic junction causes inhibition of reuptake leads to muscle contractions + fatigue
Severe and rigid abdominal pain
48
Black Widow clinical effects
Hallmark: muscular cramping (abd > chest, back); onset 30-90 min, peaks 3-12 hrs
N/V, diaphoresis, HTN, tachycardia, anxiety, agitation, irritability, weakness, H/A, periorbital edema
Bad: Shock, coma, respiratory failure
49
Black Widow Trx
No specific test
Narcotics, bentos
Antivenin: 2 vials + NS in 20-30 min (horse serum)
-inidcated for life-threatening HTN/incr HR, rest issues, refractory pain, meds, pregnant, elderly
Ca gluconate, valium as well
50
Lice
intensely pruritic wheals
waists, shoulders, axillae, neck
Eggs no easily brushed off
Try: lindane (avoid in kids/preggo); fine combing, sterilize clothes + bed
51
Scabies
Hands/feet between digits
white zigzag threadlike pattern
Trx: elevate/Lindane; calamine; oral antipruritic (ataraxic), analgesics
52
Snakebites background
8000bites, 5-15death;
90-95% rattlesnakes, copperheads, moccasins
MC time: august - Oct
M>F 9:1
```
Adults = UE> LE
Kids = LE > UE
```
dry = no venom
53
Snakes: Red, yellow, black
Red on yellow will kill a fellow; red on black you'll be fine jack
54
Snake bites clinical
venom causes local tissue injury, systemic vascular damage, HEMOLYSIS, fibrinolysis, DIC
cardinal features: one/more fang marks, localized pain, etythemia, ecchymoses, progressive edema
N/V, weakness, parenthesis mouth/tongue, METALLIC TASTE, tender lympadenopahty, incr. HR, dizzy, hematuria, Decr. platelets
55
Snake Bites test + trx
test: CBC, CMP, Coag, UA, T/S
Try: elevate, constriction bands occluding venous outflow ONLY IF DELAY TO CARE, observe x 8 hrs
Admit ALL kids
Cut and suck NOT rec. Extractor devices unproven, Abx NOT rec.
56
Snake Antivenins
Indicated for worsening swelling, coat abnormalities, systemic effects (hypotensive), all copperhead bites
ACP: 0-5mild, 10-15 mod, 15-20 severe
Polyvalent Immune: 5.2x more potent than ACP; 4-6 initial then repeated 2vials @ 6,12,18hrs
No diff between peds/adults
57
Scorpions background
found in wood piles, crevices, shoes, clothes
venom activates Na channels = immediate paresthesias, tachycardia, incr. secretions, incr. temp, diaphoresis, SLUDGE (cholinergic)
EYE ROVING
TONGUE FASICULATIONS/DIFF SWALLOW
58
Scorpion Graes
1. local pain +/- paresthesias
2. pain remote from site of sting
3. CN/Auonomic/somatic dysfxn: blurred vision, roving eye, hyper salivation, tongue fasciculation's, dysphagia, dystonia; restlessness, involuntary shaking or jerking
4. CN/autonomic and somatic nerve dyxfunction
59
Scorpion Trx
TOC: supportive (cool compress, +/- midazolam)
Anascopr: anitvenom. Supper expensive
60
Cactus
Pain
Mx foreign bodies
TOC: removal of spines and local wound care
Elmers glue works super well!
61
Drowning def
process resulting in primary resp impairment from submission/immersion in a liquid medium
Submersion = entire body; immersion = part
62
Drowning risk factors
Age: 0-4; 15-19
AA, unsupervised bath/pool, bath seat, seizure, ETOH
63
Drowning Pathophys
1. Perceived risk (struggle)
2. Last inhalation effort
3. Moment of submersion/immersion
4. Tissue hypoxia, acidosis, hypercapnia
- Loss of consciousness; involuntary rest. drive
5. Laryngospasm/aspiration
6. Resp failure + death
64
Water on Sufactant/alveoli
alveolar collapse, shunting, V/Q mismatch
Most victims ingest water during drowning. Vomiting is common and Expected!
65
Prognostic Factors
Largest: DURATION of submersion and interval time between drowning + ventilation
Good: Age < 14, CPR, CPR < 25min, Detectable pulse on arrivale
Poor: submersion > 5min, no resus > 10, fixed/dilated pupils, GCS < 5, pH < 7.1
66
Drowning Trx
All victims who require resuscitation should be evaluated in hospital
Asympt observed x 4-6 hrs
Spinal precautions not recommended
O2 if O2 < 92%
Admit x 24 hrs if survive to ER
67
Thermal burns
2nd MCC accidental death
More freq in <4 or >65
Rule of 9s
Zone of coag = loss
Zone of stasis = salvageable
Zone of hyperemia: hurts
68
Thermal Burn Degrees
1st: epidermis only; painful, red, no blisters (Sunburn)
2nd part: partially thru dermis, blisters, painful (Hot liquids)
2nd deep: thru hair follicles and sweat glands (steam/oil)
3rd: skin to fat, charred, able, painless, leathery feel
Skin graft: 2nd deep and more
69
Major Burn criteria
```
Partial thick > 25% 10-50; >20 outside range
full thick > 10;
any burn hand/face/feet/perineum
any burn crossing amor joint
circumferential limb burn
inhalational/electrical
burn+fractures
Burns in infants/elderly
```
70
Minor Burn Criteria
<15% 10-50, < 10 outside area
| Full thickness < 2%
71
Thermal Burn Treatment
All get tetanus prophy
NGT
LR x 2 large bore periph IVs
Parkland formula: 4cc/kg/% - 1/2 given in 1st 8 hours, remaining 1/2 over next 18
2-4 in 24, 1/2 in 8 the rest can wait
```
UrineOP: 0.5-1ml/kg/hr
IV narco
debride OPEN blisters
cover w/ sterile moist dressings w/o abx ointment
24hr f/u after d/c
```
72
Thermal Burns Admit criteria
```
Partial thick >15 or full >5 in 10-50
Part thick >10, full >3 outside range
all w/ burn to face, hands, get, perineum, major joint, circumferential
electrical, chemical, inhalation burn
immunocompromised
burns + trauma
```
73
Smoke inhalation
3/4 of all fire-related deaths
Suspect: facial/intraoral/pharyngeal burns, singed nasal hairs, soot in mouth/nose, hoarseness, carbonaceous sputum, wheeze
74
CO pathophys
Binds to hg to form carboxyhemoglobin
| affinity for hg 200. > O2 (leftward shift of dissociation curve)
75
When should you suspect CO poisoning?
Mx family members w/ nonspecific symptoms that resolve in ED
76
Can pulse ox distinguish hg/carboxyhg, methemoglobin?
no, but pulse CO-OXIMETRY can
77
CO-Hgb Levels + symptoms
```
<10% asymptomatic
10-30 = h/a, n/a, loss of dexterity
30-40 = confusion, lethargy, ST seg depress
40-60 = coma
>60 = death
```
78
Hyperbaric trx indicated?
```
CO-Hgb > 25-30
cardiac involvement
severe acidosis
transient or prolonged unconsciousness
neuro impriment
>36 y.o
preggos
```
79
cyanide poisoning
MCC = smoke inhalation (house fire)
also in: wool, nylon, acrylics, silk, foam, rubber, plastics; fruits (apricots, bitter almonds, cherries, peaches), cassava root, jewelry/textile industries, Na nitropresside
80
Cyanide pathophys
Disrupts mitochondrial production of ATP by binding to and inhibiting cytochrome oxidase
Causes cessation or aerobic cellular metabolism
- cellular asphyxiant
- ATP priced via ANAEROBIC pathway which lead to lactate production (>8 strongly suggestive of cyanide poisoning)
81
Cyanide Symptoms
Mild: H/A, N, vertigo, tachypnea, HTN, AMS
Severe: dyspnea, bradycardia, hypotensive, arrhythmia, unconsciousness, convulsions, CV collapse
82
Cyanide poison findings
SEVERE metabolic acidosis (2/2 lactate), usually not cyanotic, bitter almond smell
83
Cyanide Trx
O2
3 parts: Amyl nitrite (oxidizes hero to methe which combos with cyanide to form cyanomethemoglobin)
Sodium nitrite
Sodium thiosulfate
or
Vit B12 (binds with cyanide to for cyanocobalamin - excreted in urine). may cause HTN, chromaturia
84
Chemical Burns
Acids: Coag, NeCrosis, limits penetration of chem
Alkalis = liquefAction (keeps moving through)
therapy: gentlefolk hydrotherapy
Acetic acid (hair dyes) = local
Overall: Acid > Alkaline
85
Electrical background
5th leading cause of fatal occupational injury; 2nd leading COD in construction
Most involve low volts
kids < 6 MC w/ cords/sockets
AC more dangerous than DC
AC = lock, DC = thrown back
86
Order of Resistance to Electricity
```
Most: bone
fat
tendon
skin
muscle
blood
nerves (least!)
```
87
Electrical injuries patho
Cell membrane disruption, edema, coag nec, ischemia, release of myoglobin (renal fail 2/2 rhabdo)
Extent of skin damage no correlate w/ extend of below skin (burn center!)
AC may precipitate V Fib, DC causes systole
Thoracic muscle tetany, direct coronary artery spasm, and myocardial ischemia
88
Associated injuries with electricity
CP arrest is MC COD (immediate): defib if in V fib
LOC< seizure, amnesia, H/A, weakness
compartment syndrome
89
Electrical Trx
CBC, CMP, CK, myoglobin
IVF, keep UP >1cc/kg/hr
Myoglobinuria: 1/2amp Na Hco3 to each liter of NS: UO > 1.5 - 2cc/kg/hr
Tetanus prophylaxis
D/c if no evidence of electrothermal injury, normal exam, and EKG; no heme in urine
