Temperature Emergencies Flashcards
Cold urticaria
hypersensitivity to cold air or water
may lead to FATAL anaphylaxis
cold urticaria diagnosis
confirmed with cold water test during follow up
cold urticaria tx
Antihistamine
then go to anaphylaxis management if severe rxn
Chiliblains
mild but unconfortable inflammatory lesions of the skin precipitated by acute exposure to cold
12 hrs of exposure
pernio
aka chilblains
pruritus or burning paresthesia
hands, ears, lower legs, feet MC
re warming and chilblains
may cause formation of tender blue nodules that persist for days
tx of pernio
affected skin rewarmed, bandaged, elevated
some evidence of pharm tx in European studies
immersion injury patho
direct injury to soft tissue following prolonged cooling in wet conditions
vasoconstriction, red cell and thrombocyte pudding, tissue edema, nerve and small vessel injury
clinical features of trench foot
numbness and tingling of affected tissue
pale, mottled, anestehtic, pulseless, immobile
hyperemic phase
immersion injury
hours after re=warming, severe burning pain and reappearance of proximal sensation
late phase immersion injury
excessive sweating and cold sensitivity
persist for months to years
tx of immersion in jury
supportive +/- pain control
clean, warm, dry bandage, elevate affected area
frostbite
frozen tissue secondary to heat loss
causes ice crystal formation in superficial or deep tissue
MC in peripheral locations
clinical summary frostbite
numbness + sensory loss in digit
thawed tissue but mottled blue, violet, yellow or waxy color
hyperemia
Favorable prognostic signs frostbite
return of normal sensation/color/warmth
edema w.in 3 hrs of thawing
early formation of bulla to tips of digit
poor prognostic indicators frostbite
lack of edema
small dark hemorrhagic bulla that DO NOT go to tips of digit
necrotic tissue
superficial frostbite (1st degree)
frost nip
numbness, white tissue, erythema
superficial frostbite (2nd degree)
clear vesicle or blebs with erythema
deep frostbite (3rd degree)
hemorrhagic blisters
not extend to tip of appendage
deep frostbite (4th degree)
necrotic tissue involving muscles, tendon bone
tx of frostbite (gen)
SHOULD NOT be attempted until risk of refreezing is eliminated
soak warm water (98-102) for 20-30 MIN
elevation + pain + PCN
hypothermia
core temperature below 95 degrees
hypothermia clinical features
tachycardia –> Bradycardia
ECG prolonged (PR –> QRS –> QT)
Osborn J wave/hypothermic hump
MUST get proper vitals (esophagus)
atrial arrhythmia (resolve)
causes of body temp drop
conduction
convection
radiation
evaporation
conduction
transfer of head by direct contact down concentration gradient
I.e. submersion
convection
movement o heated material causes transfer of heat
I.e. wind
radiation
heat loss by environment (ie non insulated areas)
evaporative
heat loss thru vaporization
heat is conserved by
peripheral vasoconstriction and behavioral responses
MC behavioral responses are affected
heat gain is increased by
shivering and non shivering thermogenesis
hypothalamus attempts to stimulate heat production (shiver) and increased thyroid catecholamine and adrenal activity
mild hypothermia
89.6-95 F
shivering tachypnea/tachycardia/hypertension ataxia/dysarthria loss of fine motor coordination confusion/lethargy
moderate hypothermia
89.6-82.4 F
bradycardia, Osborn waves AMS slowed reflexes cold diuresis pupil dilation
severe hypothermia
< 82.5 F
unresponsive/coma HoTN VFib/Asystole Acidemia Loss of reflexes
labs and hypothermia
BMP (watch K)
HcT will rise according to 1C change
active rEWARMING
ALL pts
warmed IV fluid and humidified warmed O2, warmed water immersion
MUST monitor closely
passive rewarming
SLOW method
remove from environment, remove wet clothes, give blankets
severe hypothermia
lavage warm fluids in all areas
hemodyalis, heart bypass
forms of heat loss
radiation and evaporation
increased internal heat production, external heat exposure
impaired heat dispersion
Exogenous heat
high ambient temp (minimized radiation loss)
high humidity (minimized heat loss)
direct sunlight
endogenous heat
physical activity
drugs (Molly, coke, meth, bath salts, LSD, PCP, etc)
impaired heat dispersal caused by
CV disease obesity extremes of age unventilated confinement dehydration
acclimatization
body ability to acclimize to heat
allows it to protect kidneys and increase sweat, improved cardiac response to vasodilation
heat edema
cutaneous vasodilation
resolves spontaneously
DO NOT USE DIURETICS
heat rash
block sweat ducts = rash due to rupture and inflammation
prevent with loose clothes
tx: antihistamine
heat syncope
peripheral vasodilation + decreased vasomotor tone + volume depletion
tx: remove from heat source, fluids, rest
heat cramps
dehydration + electrolyte imbalance
give hydration with electrolytes, IV fluids
heat exhaustion clinical features
elevated body temp, <105 F
fatigue/weakness/syncope
profuse sweating
tx of heat exhaustion
cool with fans.ice
oral rehydration w/electrolyte fluid
monitor vital signs (Urine output and orthostatic vitals)
heat stroke clinical features
body temp >105
hyperdynamic cardiac parameters
oliguria, anhidrosis
CNS dysfunction
tx of heat stroke
ABCs, IV access, IV boluses, foley and NG tube
rapid cooling, GOAL is 100.4 F
methods of cooling in heat stroke
evaporation immersion internal cooling
adjunct therapy heat stroke
Anti-pyretics have NO role
benzos
renal failure can have dialysis
