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Rosens > 128 Hypothermia, Frostbite and Nonfreezing Cold Injuries > Flashcards

128 Hypothermia, Frostbite and Nonfreezing Cold Injuries Flashcards

1
Q

Hypothermia defn

A

temp <35 celcius

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2
Q

What variables contribute accidental hypothermia?

A

exposure
old age
poor health
inadequate nutrition
meds and intoxicants

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3
Q

Compensatory responses to heat loss x4

A

convection
conduction
radiation
evaporation

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4
Q

Cold stress increases preshivering muscle tone, potentially __ heat production

A

doubling

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5
Q

How long does heat production from shivering last?

A

only few hours due to glycogen depletion and fatigue

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6
Q

Shivering thermogenesis: how much does this increase BMR?

A

up to 5x which rapidly incr o2 consumption

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7
Q

What part of the CNS modulates shivering?

A

posterior hypothalamus and sc

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8
Q

What part of the CNS is in charge of nonshivering heat conservation and dissipation?

A

preoptic anterior hypothalamus

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9
Q

MC causes of accidental hypothermia

A

convective heat loss to cold air

conduction and convection in cold water

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10
Q

5 ways heat loss occurs?

A

radiation
conduction
convection
respiration
evaporation

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11
Q

How much does wet clothing increase heat loss?

A

3-5x

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12
Q

Greater losses of cutaneous and respiratory heat in which kind of environments?

A

cool
dry windy

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13
Q

When there is no sweating, how is more heat lost?

A

radiation
convection

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14
Q

When the core temp is between 30 to 37, what mechanisms generates heat?

A

vasoconstriction
shivering
nonshivering basal and endocrine thermogenesis

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15
Q

When does shivering tend to stop ? (temp range)

A

30 to 24

BMR decr

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16
Q

At temp below 24, what happens to autonomic and endocrine mechanisms of heat conservation?

A

inactive

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17
Q

MC heart rhythm in hypothermia?

A

bradycardia

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18
Q

Cold stress - temp 37-35 - what are the characteristics of this you will see in a patient?

A

shivering
incr metabolism

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19
Q

Mild hypothermia: Temp 35 to >32 - what are the characteristics of this you will see in a patient

A

increased shivering and thermogenesis
incr BMR
normal bp
max resp stimulation
ataxia
apathy
amnesia

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20
Q

Moderate hypothermia: Temp 32 to 29 - what are the characteristics of this you will see in a patient

A

stupor with a 25% decr in o2 consumption
incr shivering thermogenesis
atrial fib/dysrhythmias, poikilothermia, pulse and cardiac output 2/3 of N, insulin ineffective, progressive decrease in consciousness and LOC can be seen

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21
Q

Severe hypothermia: temp 28 to 19

A

vent fib susceptible with 50% decr in o2 consuption and pulse

loss reflexes

major a-b differences, no reflex or response to pain

cerebral blood flow 1/3 normal, co 45% normal, pulmonary edema possible to develop

no corneal or oculocephalic reflex

at 22 -max risk of vfib and 75% o2 consumption

at 20 lowest resuption of cardiac electromech activity, 20% of normal

at 19 flat ecg

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22
Q

What is an osborn J wave?

A

junction of QRS and ST segment

J waves are normally upright in aVL, aVF, and the left precordial leads

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23
Q

What conditions other than hypothermia can a J wave be seen in ?

A

cardiac ischemia
sepsis
cns lesion
hypocalcemia

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24
Q

What arrh are mc in mod-sev hypothermia?

A

atrial and vent dysrh

prolonging of cardi cycle - PR prolong, qrs, qtc

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25
Q

At less than what temp is afib common?

A

<32

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26
Q

Core temp afterdrop - what is this?

A

decr in individual’s core temp after removal from the cold

contribution of equilibriation core cool to periphery and countercurrent cooling of blood to cold tisues in periphery before reurning to warm = greater effect

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27
Q

At what temp of hypothermia do we see cns alterations?

A

33.5

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28
Q

Renal system changes when faced with hypothermia

A

diuresis
dilute, does not clear nitrogenous waste

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29
Q

Hypothermia and the resp system - what happens?

A

initially stimulates incr RR
then decr in minute vol (decr 50% with an 8 deg decr in temp)

can cause acidosis with rentension, hypercapnia

viscous bronchorrhea, decr ciliary motility, noncardiogenic pulmonary edema

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30
Q

What 4 categories may include factors predisposing someone to hyperthermia?

A
  1. decr heat production
  2. impaired thermogenesis
  3. miscell assoc clinical syndromes
  4. impaired thermoregulation
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31
Q

8 examples of decreased heat production

A

endocr failure
hypopituitarism
hypothyroid
diabetes
hypoglycemia
age extremes
inactivity
nalnutrition

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32
Q

8 examples of incr heat loss

A

environmental
immersion
nonimmersion
induced vasodilation
pharmacologic
toxicoloic
burns
psoriasis
cold infusions
iatrogenic

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33
Q

8 examples of impaired thermoregulation predisposing to hypothermia

A

diabetes
cns failure
cva
toxicologic
metabolic
hypothalamic dysfunc
parkinson
anorexia
neoplasm
MS

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34
Q

8 predisposing factors to hypothermia under miscellanous conditions category

A

recurrent hypothermia
sepsis
pancreatitis
carcinomatosis
uremia
vascular insuff
sarcoidosis
GCA
paget’s disease
hodgkin disease

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35
Q

How does ethanol effect hypothermia?

A

etoh metabolized slowly in hypothermia
directly suppresses activity of posterior hypothalamus and mamillary bodies
decr vasodilation and shivering

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36
Q

What medication classes can impair thermoregulation leading to hypothermia?

A

antidepressants
mood stabilizers
antipsychotics
anxiolytics
general anesthesia
OD: organophosphates, opioids, sedatives, barbituates, co

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37
Q

Abnormal plasma osmolality may cause hypothalamic dysfunction - examples?

A

uremia
lactic acidosis
dka
hypoglycemia

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38
Q

Major RF of hypothermia in trauma pt

A

extremes of age
severe injury intoxication
large transfusion requirements
prolonged field, ED, operating room times

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39
Q

What is paradoxical undressing?

A

widely reported in hypothermic pt - related to periheral vasoconstrictive changes of hypothermia (final preterminal effort)

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40
Q

Above 22 degrees, it should be assumed that nonreactive dilated pupils are more likely related to…

A

inadq tissue perfusion as opposed to hypothermia

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41
Q

*Neuromuscular examination may reveal stiff posture, pseudo– rigor mortis, or opisthotonos. Reflexes are usually hyperactive to 32°C (89.6°F) and then become hypoactive, disappearing around 26°C (78.8°F). Cremasteric reflexes are absent because the testicles are already retracted. The plantar response usually remains flexor until 26°C (78.8°F). The knee jerk reflex is the last reflex to disappear and the first to reappear with rewarming. Diagnosis of CNS disorders, includ- ing spinal cord lesions, may be obscured by hypothermia. From 30°C to 26°C (86°F to 78.8°F), both contraction and relaxation phases of the reflexes are equally prolonged. If intact, the ankle jerk is helpful to diag- nose hypothermic myxedema. Myxedema characteristically prolongs the relaxation phase more than the contraction phase.

A

-

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42
Q

Name 5 signs of hypothermia you can see on HEENT exam

A

Mydriasis
Decreased corneal reflexes
Extraocular muscle abnormalities
Erythropsia (altered color perception)
Flushing
Facial edema
Epistaxis
Rhinorrhea
Strabismus

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43
Q

Name 5 signs of hypothermia you can see on CV exam

A

Initial tachycardia
Subsequent bradycardia
Dysrhythmias
Decreased heart tones
Hepatojugular reflux
Jugular venous distention Hypotension

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44
Q

Name 5 signs of hypothermia you can see on resp exam

A

initial tachypnea
advenititious sounds
bronchorrhea
progressive hypoventilation
apnea

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45
Q

Name 5 signs of hypothermia you can see on GI exam

A

ileus
constipation
abdo distention/rigidity
poor rectal tone
gastirc dilation inneonates or adults with myxedma

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46
Q

Name 5 signs of hypothermia you can see on GU exam

A

anuria
olugira
polyuria
testicular torsion

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47
Q

Name 5 signs of hypothermia you can see on neuro exam

A

Depressed level of consciousness
Ataxia
Hypesthesia
Dysarthria
Antinociception
Amnesia
Initial hyperreflexia
Anesthesia
Hyporeflexia
Areflexia
Central pontine myelinolysis

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48
Q

Name 5 signs of hypothermia you can see on psychiatric exam

A

Impaired judgment Perseveration Mood changes Flat affect
Altered mental status Paradoxical undressing Neuroses
Psychoses
Suicide
Organic brain syndrome

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49
Q

Name 5 signs of hypothermia you can see on MSK exam

A

Increased muscle tone Shivering
Rigidity or pseudo–rigor mortis Paravertebral spasm Opisthotonos
Compartment syndrome

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50
Q

Name 5 signs of hypothermia you can see on derm exam

A

Erythema
Pernio
Pallor
Frostnip
Cyanosis
Frostbite
Icterus
Popsicle panniculitis (inflammation of the cheeks; also called “cold panniculitis”) Sclerema (hardening of subcutaneous tissue)
Cold urticaria Ecchymosis Necrosis Edema Gangrene

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51
Q

What diagnostic testing is reasonable in hypothermia?

A

glucose
cbc
cmp
lipase
coag studies
vbg/abg –> do not temp correct
etoh
+/- tsh +/- cortisol +/- trop

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52
Q

Ideal acid base goal: pH and paco2 in hypothermic pt

A

uncorrected (as normal analyzers warm blood to 37, increasing pp of dissolved gases so abg higher o2 and co2 and lower ph than in vivo values
pH 7.4, co2 40

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53
Q

In normothermia, ph decreases by 0.08u for efvery 10mhg incr in paco2. At 28 degree body temp, how does this change?

A

cold buffers poorly. decreases in PH double

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54
Q

Hematocrit changes in cold: incr _% for every 1 degree fall in temp

A

2

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55
Q

How does cold body temp change leukocytes and plt?

A

sequesteration in spleen, liver, splanchnic circulation –> so watch out as normal can still have infection

56
Q

How does potassium tend to change in hypothermia?

A

indepent of hypothermia: assoc wih metabolic acidosis, rhabdo or renal failure and tends to obscure premonition of ecg changes

57
Q

When does hypokalemia occur in hypothermia?

A

if chronic hypothermia - as K enters m rather than K diruresis
a decline in this despite a decreasing serum ph is caused by IC ph fluxes greater than extracellular fluxes

58
Q

What conditions to consider if hypokalemic in hypothermia?

A

dka
hypopity
siadh/inapp adh
diuretic thearpy
alcoholism

59
Q

If K < ? in rewarming, when to supplement

A

3

60
Q

BG clues in hypothermia - what does this mean?

A

acute hypothermia elevated BG due to glycogenolysis, diminished insulin release and inhibits cellular membrane glucose carrier ststems

subac and chr hypothermia cann produce glycogen depletion –> hypoBG

rewarming can also cause hypoglycemia due to cold induced renal glycosuria

61
Q

Insulin is ineffective below which temp

A

30

62
Q

What potential kidney issue is comon in hypothermia?

A

rhabdo

63
Q

Why may coagulopathies occur in hypothermiua?

A

enzyme actviity of activated clotting factor depressed by cold

64
Q

What concerning coagulopathy may ocur with hypothermia?

A

dic

65
Q

Basic assessment of a cold patient:
1-5

A
  1. From outside ring to center: Assess consciousness, movement, shivering, alertness 2. Assess whether normal, impaired or no function
  2. The colder the patient is, the slower you can go, once patient is secured
  3. Treat all traumatized cold patients with active warming to upper trunk
  4. Avoid burns: Following product guidelines for heat sources; check for excessive skin redness
66
Q

Cold stressed but not hypothermic: how to tx patient?

A

reduce heat looss - add dry clothing
provide high cal food or drink
move around/exercise to warm up

67
Q

Cold stressed but not hypothermic: what might you see?

A

conscious
movement normal/slight imapired
shiver
alert

68
Q

Mild hypothermia: how to tx?

A

handle gently
pt sit/lie down x30mins min
insulate/vapor barrier
give heat to upper trunk
high cal food and drink
monitor min 30 mins
evavuate if not improved

69
Q

Mild hypothermia: what might you see?

A

conscious
impaired movement
shiver alert

70
Q

Miderate hypothermia: tx

A

handle gently
keep horizontal
no stand/walking
no drink or food
insulate and vapor barrier
heat upper trunk
vol replacement with warm IVF 40-42 deg
evacuvate carefully

71
Q

Mod hypothermia: what might you see?

A

conscious
impiared movement
no shiver
not alert

72
Q

Severe hypothermia: how to manage

A

tx as mod and
if no obvious vital signs: 60s breathing/pulse check or assess cardiac function with monitor
if no breathing/pulse then start cpr

73
Q

severe hypothermia: what might you see?

A

if cold/unconscious: assume severe

74
Q

Key q prehospital hx

A

preexisting cardiopulmonary, neuro or endocrine disease
duration of exposure/outdoor conditions, how discovered and assoc injuries/predisposing conditions

75
Q

What temp is the myocardium irritable?

A

below 32 deg

76
Q

Best way to get a temp?

A

rectal at least 15cm into feces but lags behind core
epitympanic but not suitable for field
esophageal probe lower third esophagus around 24cm below larynx ideal once intubated

77
Q

is ett co2 reliable below N temps?

A

no

78
Q

moderate and severe hypothermia: what to assess u/o and fluid shifts?

A

foley

79
Q

vol resus in a mod-severe hypothermic pt - how to do?

A

eceive a 500-mL fluid challenge of warmed normal saline. Avoid lactated Ringers solu- tion because the cold liver metabolizes lactate poorly. Fluids admin- istered via the intravenous (IV) route should be warmed to 40°C to 42°C (104°F to 107.6°F).

80
Q

How to warm a fluid bag

A

warmer
microwave
IO or IV
countercurrent heat excahnger

81
Q

How do factors in Adv life support change in hypothermia? (nonpharm aspect)

A

-co, cerebral and myocardial blood flow are much less than those during northomothermic closed chest compressions
- heart as a passsive conduit and phase alterations in intrathoracic press are equal on all cardiac chambers
- mv patent in systole and blood continues to circulate through L side of heart
-chest wall elasticity and pulmonary compliance are decreaesd - more force needed
- rigor mortis and fixed dilated pupils not appropriate to withhold cpr

82
Q

How do factors in Adv life support change in hypothermia? cardiology aspects

A

-no IM meds as poor absrob from vasoconstricted sites
-Defib at normal levels usually not super successful until core temp above 30 (can occassionally attempt until then)
-can external pace if brady DO NOT tranvenous pace
-epi x3 only til >30

83
Q

When are antibiotics indicated in hypothermic children and when?

A

<3mo
after cultures obtained

84
Q

Cold stress and cortisol - how does this work?

A

acute cold initially stimulates cortisol
failure to rewarm consider adrenocirtocal insuff and can give 100mg IV hydrocortisone

only thyroxine if myxedema 250-500microgram slow IV

85
Q

Passive rewarming strategies: list 3

A

covering patient with insulated material
ambient temp >21 deg
remove wet clothes and add dry

86
Q

When core temp exceeds 32 deg celscius, what is major source of heat production?

A

shivering

87
Q

rewarming rate for mild hypothermia recommended?

A

0.5 to 2 deg/ hour

88
Q

Name 6 indications for active rewarming

A

cardiovascular instability
mild to severe hypothermia
inadequate rate of rewarming or failure to rewarm
endocrine insuff
trauma
traumatic or tox peripheral vasodilation
secondary hypothermia impairing thermoregulation

89
Q

name 5 ways to actively rewarm a patient

A

bare hugger blanket with warmed air
heated humidified air - neublizer if spontaenous resp vs ETT
PD
heated irrigation of gluids - gastric/colonic or closed thoracic lavage (one in 2-3 ICS and another 5-6th ICS
Endovascular through femoral vein cath
diathermy trhough ultrasound or low freq microwave irradiation
ECMO - VA

90
Q

Ways to increase the 41 deg max many heated cascade nebulizers face?

A

reduction of tubing length from 2m
add. mmore heat source
disable humifier safety system
place temp probe outside pt circuit

91
Q

PD dialysis: how to set this up for hypothermia?

A

double cath system suction at outflow incr flow to 6L/hour

also hepatic warms

92
Q

Contraindications to truncal diathermy/use of microwaves or ultrasound to generate heat

A

frostbite
burns
significant edema
metallic implants/PM

93
Q

4 types for Extra corporeal blood rewarming

A

venovenous
HD
continous AV rewarming
extracorporeal circulation cardiopulmonary bypass - ecmo

94
Q

How does venovenous rewarming work?

A

blood removed by large cath
heated 40 deg
retruned through recond venous cath at 150-400ml/min

95
Q

How does AV rewarming work?

A

se of percutaneously inserted femoral arterial and contralateral femoral venous catheters. Heparin-bonded tubing circuits obviate the need for systemic anticoagulation. The blood pres- sure of a spontaneously perfusing, traumatized, hypothermic patient creates a functional arteriovenous fistula by diverting part of the car- diac output from the femoral artery through a commercially available countercurrent heat exchanger. The heated blood is then returned with admixed heated crystalloids through the femoral vein. Continuous AV rewarming avoids the need for specialized equipment and a perfusion- ist, which are necessary for cardiopulmonary bypass. The average rate of rewarming is 3°C to 4°C/hr (5.4°F to 7.2°F/hr). Because the catheters are 8.5 Fr, the patient should weigh at least 40 kg.

96
Q

How does CPB circuit work for extracorporeal blood rewarming?

A

Full circulatory support with pump and oxygenator
Perfusate-temperature gradient, 5°C–10°C/hr (9°F–18°F/hr)
Flow rates, 2–7 L/min (average, 3–4 L/min)
Rate of rewarming up to 9.5°C/hr (18.9°F/hr)

preservation of flow if mechanical cardiac activity is lost during rewarming

97
Q

Complications of rapid rewarming - list 4

A

dic
hemolysis
pulmonary edema
atn

98
Q

Grave prognostic indicators in hypothermic pt

A

IV thrombosis with fibrinogen <50
ammonia >250
hyperkalemia >10-12 vs asphyxia in avalange and cold = hypok >7

99
Q

Frostbite defn

A

issue freezing with formation of ice crystals in the tissues

100
Q

Immersion injury/trench foot defn

A

nonfreezing injury resylting from exposure to wet cold

101
Q

Pernio/chilblains

A

nonfreezing injury in susceptible inds after repetitive exposure to dry or damp cold

102
Q

Freezing injury cascade 3 ph

A

prefreeze
freeze thaw
vascular stasis and progressive ischemia

103
Q

Prefreeze phase of freezing injury cascade includes?

A

Superficial tissue cooling
Increased viscosity of vascular contents Microvascular constriction
Endothelial plasma leakage

104
Q

freeze thaw phase of freezing injury cascade includes?

A

Extracellular fluid ice crystal formation
Water movement across cell membrane
Intracellular dehydration and hyperosmolality
Cell membrane denaturation or disruption
Cell shrinkage and collapse

105
Q

vascular stasis and progressive ischemia phase of freezing injury cascade includes?

A

Vasospasticity and stasis coagulation
Arteriovenous shunting
Vascular endothelial cell damage and prostanoid release Interstitial leakage and tissue hypertension
Necrosis, demarcation, mummification, or slough

106
Q

How does skin cooling activate cns?

A

anterior hypothalamus, causing cat- echolamine release, thyroid stimulation, shivering thermogenesis, and peripheral vasoconstriction. People are physiologically adapted to tropi- cal conditions. In cold conditions, humans have a limited ability to pro- tect themselves against decreased core temperature. Behavioral responses are far more effective if adequate clothing or shelter is available.

107
Q

How do toes, fingers, ears, and nose shut down in the cold

A

Have lots of arterial venous anastomosis.

Cooling of digits to about 15°C results in maximum peripheral vasoconstriction with minimal blood flow, beyond this produces cold induced vasodilation, which follows approximately a 5 to 10 minute cycle to interrupt vasoconstriction to protect the extremity

108
Q

At what temperature does frostbite occur?

A

Tissue cooled below 0°C, required temperature of at least -4 and maybe as low as -10 and some conditions

109
Q

How does ice crystal formation tend to occur?

A

Initially extracellular.
Water than exits the cells to maintain osmotic equilibrium.
Cellular dehydration, increases the intracellular osmolarity electrolyte concentrations.
After approximately 1/3 of the cell volume is lost the cell collapses and dies

110
Q

What is found in the clear vehicles of frostbite blisters versus haemorrhagic

A

Prostaglandins
Prostaglandins, thromboxane and tend to occur more in the sub journal vascular plexi

111
Q

Why is it appropriate to wait for frostbite injuries to declare themselves?

A

Oedema progresses for 48 to 72 hours after tissue is thawed, necrosis becomes apparent after this and dry gangrene in tends to be superficial in comparison to arterial sclerosis induced full thickness gangrene

112
Q

Name six physiologic factors that predispose to frostbite

A

Genetic
Core temp.
Previous cold injury.
Lack of acclimatization
Dehydration.
Exertion
Trauma
Durham disease.
Physical condition conditioning.
Diaphoresis
Hyperhidrosis
Hypoxia

113
Q

Name four mechanical factors that can be exposed to cold injury

A

Constricting your wet clothing.
Tight boots
Beaver barrier.
Inadequate insulation.
Immobility or cramped positioning

114
Q

Name four psychological causes her predisposing factor to cold injury

A

Mental status
Fear
Panic.
Attitude
Peer pressure
Fatigue.
Intense concentration on task
Hunger
Nutrition
Intoxicant

115
Q

Name eight environmental predisposing factors to cold injury

A

Ambient temperature
Humidity.
Duration of exposure.
Windchill.
Altitude associated conditions.
Quantity of exposed surface area.
Heat loss
Aerosol propellants
Cardiovascular
Hypertension,
Arthrosclerosis
Reyno syndrome
Anemia
Sickle cell disease,
Diabetes
Vasoconstrictors or dilators

116
Q

What is frostnip?

A

Superficial freezing injury manifested by transient numbness and tingling that results after re-warming with no tissue destruction occurring

117
Q

What is the nearly universal symptom of frostbite bite?

A

Numbness

118
Q

List five favourable symptoms after re-warming for frostbite

A

Normal sensation, warmth, color.
Softly will subcutaneous tissue suggest a superficial injury
Early formation of large labs with relatively clear fluid, extending to the fingertips is more favourable than delayed appearance of smaller
Oedema

119
Q

What are more concerning symptoms on frostbite evaluation?

A

Residual violaceous Hughe after re-warming.
Delayed appearance of smaller more proximal haemorrhagic vehicles indicate damage to subdermal vascular plexi
Little oedema

120
Q

List of four historical classifications of frostbite

A

One. Anaesthesia erythema.
Two. Superficial fasciculations surrounded by oedema and erythema.
Three. Deeper haemorrhagic cycles.
4th degree extension into subcutaneous tissues, including bone and muscles.

121
Q

Classification of frostbite into superficial versus deep

A
122
Q

Best method for classifying frostbite is based on cyanosis immediately after rapid thawing and warm water. Name grades.

A

Grade one: no cyanosis, grade 2 cyanosis limited to distal, failings predict only soft tissue amputation and equality involving only males, grade 3 cyanosis of intermediate and proximal phalanges predict bone, amputation, and functional sequelae.
For cyanosis over carpool or tarsal bones, predict, limb, amputation with severe functional Siwell

123
Q

Should rewarming be started in the field

A

Only if it will be uninterrupted as intermittent will cause worse damage

124
Q

How to manage frostbite in the emergency department

A

Stabilize, hypothermia and other life-threatening injuries.
Rapidly re-warm, completely frozen or partially thawed tissue emerging in gently circulating water that is carefully maintained between 37 to 39°C. If the tissue water is greater than 42°C, there will be injury.
Part of colour should have returned and feel pliable, which usually requires 15 to 30 minutes of submersion. Do not massage during but can do active movement.
Give analgesia
Watch for record temperature after drop which is risk factor for ventricular fibrillation

After thawing, elevate, injured extremities to minimize edema, formation, sterile dressing, loosely, and handle areas gently.

Large blisters can be left intact, debrided, or aspirated, haemorrhagic blisters are aspirated rather than debrided, though consider being careful during these injuries as may make this worse

125
Q

When to consider thrombolysis with TPA in frostbite injuries

A

Grade 3 year grade 4 injury with risk for significant tissue loss
That the injury has not undergo freeze thaw refreeze
Is within 24 hours of thawing
No contraindications to thrombolysis

126
Q

How to treat frostbite with thrombolysis

A

Intro, arterial TPA and geography with intra-arterial vasodilators, including nature, glycerine and nicardipine.
If flow is not reestablished, consider catheter directed TPA infused with a bolus of 2 to 4 mg followed by an infusion of .5 to 1 mg/h. Heparin is also given at 500 units per hour through the catheter.
Angiogram are repeated every 8 to 12 hours.
Treatment is stopped in perfusion is restored pour up to 48 hours

Other option is to use a bone scan: one regimen uses loading dose of Alta plays 0.15 mg per kilogram IV over 15 minutes and then an infusion of 0.15 mg per kilogram perh for six hours and repeat bone scan to evaluate reperfusion . Then treat with an oxy Perrin 1 mg per kilogram subcutaneous twice daily for 14 days.

127
Q

When to consider ILOPROST for frostbite

A

Grade 2 to 4 frostbite injury.
Infused within 48 hours of thawing.
Combined with TPA inappropriate settings for grade 3 to 4 frostbite I’ve seen within 24 hours who meet indications for TPA

128
Q

Why does trench foot occur?

A

Prolonged exposure to wet cold the temperature is too high to cause frostbite or from sweat

129
Q

Name the four stages of immersion injury/trench foot

A

One. Cold exposure, numbness is most common and extremities may appear bright red to become pallor white due to extreme basil restriction.
Two. After cold exposure, during re-warming peripheral blood flow slowly returns and extremities may become modelled pale blue. Extremities remain cold and numb, usually last for a few hours, but can persist for several days.
Three. Blood flow increases markedly and the extremity becomes hot and red with bounding pulses while the micro circulation is sluggish as evidenced by cap refill. Numbness gives away to severe pain, typically even with light touch. Oedema often develops.
Four. Lime generally appears normal after hyperaemia stage except in case with tissue loss/necrosis, but pain may persist. The necrotic tissue in the third stage may become gangrenous and is lost this stage can last from weeks to years or be permanent.

130
Q

Who is at risk for CHILBLAINS

A

Young woman with Reyno phenomenon, SLE or antiphospholipid antibodies

131
Q

Where does chill planes tend to affect people?

A

Face, dose of hands, and feet, pre-tibial

132
Q

How to treat an immersion in injury

A

Treat hypothermia
Volume replacement with warm IV fluid if necessary.
Immersion injury should be allowed to rework slow room temperature, do not rapid re-warm or rub the foot, do not use medication’s, if necessary being in a local cooling or cool room with a fan lowers metabolic requirements and improved pain in edema, but should be continued until hyper resolves

Amitriptyline 50 to 100 mg orally at bedtime as the treatment of choice for pain after warming

133
Q

Chillblains treatment

A

Drying the skin if it’s down and gentle massage if tolerating

134
Q

EMS notifies your emergency department that an unknown male who has found out and is being transported. No history available. Paramedics report that the patient’s pulse is 42 bpm and blood pressure is difficult to obtain. Spontaneous respirations are presence derivative 10 breasts per minute. ECG show sinus product of cardiac faxed in before patient’s arrival. What treatment should you administer before the patient arrives?

A

Warm the patient

135
Q

Which of the following complication should be anticipated when re-warming patients with hypothermia. A. Hyperkalemia, B. Hyponatraemia C. Hypertension D. Rado.

A

Hypertension, as usually volume deplete

136
Q

A 30-year-old woman in cardiac arrest is brought to the ED by EMS. She was intubated in the field and chest compressions have been performed. She is 25°C. I’m placed on the cardiac monitor. She appears to be in ventricular fibrillation. A defibrillation attempt is made, but she remains in ventricular fibrillation and nurse resumes for writing chest compressions and asked for further instructions. What should be done next?

A

Warm the patient

137
Q

The 27-year-old homeless men complains of numb feet. He was sleeping outside overnight and it was -20 outside. The feet appear white and waxy. What is the best way to reward them?

A

Warm water immersion concerning for frostbite

Rosens (59 decks)

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