Heat Illness and Heat Stroke

							Heat Illness and Heat Stroke

       Amanda Ellis, DO
           Heat Stress
The feeling of discomfort and
physiologic strain that results from
exposure to a hot environment

Core temperature remains
NORMAL
       Heat Exhaustion
Mild dehydration
Core temperature 100.4°-104˚
Profuse sweating
Thirst, nausea, vomiting, headache,
muscle cramps
May feel faint
             Heat Stroke
Core temperature >104º and CNS
dysfunction
Severe dehydration with associated Na
abnormalities
Flushed, hot, dry skin
    Anhydrosis
CNS changes: dizziness, vertigo, syncope,
confusion, delerium, ataxia
    May be unconscious
Shock
     Classic vs Non Classic
         Classic              Exertional
Non exertional          Affects actively
overheating             exercising individuals
More insidious onset    Athletes, soldiers at
Often during heat       risk
waves                   Hot, humid weather
Vulnerable population   increases risk
at risk: infants, DD,
elderly
Heat Stroke Complications
Liver failure
Rhabdomyolisis
DIC
ARF
Mortality up to 13%
    In high school athletes heat stroke is the third
    leading cause of mortality
Treatment of Heat Exhaustion
               Immediate removal
               from the heat
               source
               Hydration- oral or IV
 Treatment of Heat Stroke
Remove from heat
Cool the patient
rapidly to less than
102.2°
     Immersion in ice
     water
      cool IVF-cool
     gastric/bladder
     lavage
     Ice packs to
     groin/axilla
 Treatment of Heat Stroke
IV rehydration
Vasopressors to maintain perfusion
Correct hematologic abnormalities as
needed
Phenytoin if necessary for seizure
control
Monitor for cerebral edema
Supportive treatment of hepatic and
renal failure
             Outcome
Severity of injury related to duration of
hyperthermia and height of
temperature
Heat Exhaustion--full recovery
Mild Heat Stroke--full recovery
Mod-severe heat stroke--higher risk of
sequelae if core temp >107.6º
                Prevention
          Risk assessment based on Heat Index
    Evaporation is the principle mechanism of heat loss
This mechanism becomes ineffective above humidity of 75%
             Prevention
Hydration
Electrolyte solutions
500mL 2hrs prior to
exercise
250mL every 20
minutes
Athletes should
acclimate to warm
temps prior to
activity