Updated: 6/14/2021

Hyperthermia/Heat Injuries

0%
Topic
Review Topic
0
0
N/A
N/A
Questions
5
0
0
Topic
Snapshot
  • A 16-year-old football player is brought to the school nurse by his teammates with extreme fatigue and altered mental status in early August. He refuses to be evaluated by his sports coach. Temporal temperature is 103°F (39.4°C). With restraining support from the teammates, the nurse records a rectal temperature of 105°F (40.5°C). The nurse informs the coach and quickly removes the athlete's equipment and clothing to facilitate cooling. The nurse then calls the ambulance to transfer the patient to the local hospital. His pretransfer rectal temperature is 102°F.
Introduction
  • Hyperthermia
    • elevation of core body temperature 96.8 - 99.5 °F (> 36 - 37.5 °C) due to failure of thermoregulation
  • Hyperthermia is NOT fever
    • fever is induced by cytokine activation during inflammation
    • regulated at hypothalamus
    • however, difficult to distinguish hyperthermia from fever
  • Heat-related illnesses can be multifactorial
    • can be exertional (e.g., athlete overexertion)
    • can be nonexertional (e.g., elderly person with dementia; immobile patient)
    • can be medication-induced (e.g., anticholinergic/neuroleptic medications)
Presentation
  •  Heat exhaustion and heat stroke definitions overlap
    • heat exhaustion (HE)
      • ≤ to 104°F
      • non-specific malaise, headache, fatigue
      • no coma/seizures
      • symptoms due to loss of circulating volume caused by heat exposure
        • water depletion
          • symptoms due to inadequate replacement of fluids
        • salt depletion
          • symptoms due to inappropriate replacement with hypotonic fluids
          • e.g., water, juice
    • heat stroke (HS) 
      • > 104°F
        • exertional HS 
          • usually younger, more active demographic
          • diaphoretic skin
          • may have DIC, AKI, rhabdomyolysis, lactic acidosis
        • nonexertional HS 
          • usually older, poor, sedentary, immobile demographic
          • hot, dry skin
          • altered mental status, delirium, coma, and seizures
    • heat syncope 
      • no specific temperature
      • syncope due to poor CNS perfusion
        • cutaneous and skeletal muscle vasodilation shunts blood from CNS to periphery
        • worsened by dehydration
 Evaluation and Management
  • Primary and secondary survey with resuscitation  
    • secure airway if seizure/aspiration risk is high
    • fluid resuscitation with intravenous isotonic fluids (NS/LR) 
  • Best diagnostic test: rectal temperature
  • Best initial step: anything that cools patient rapidly 
    • remove any layers of equipment/clothing
    • cold water and ice water immersion therapy
    • goal is to cool core temperature 0.3-0.5°F/min to 100-102°F
  • Avoid antipyretics (e.g., aspirin, Tylenol)
  • Transfer patient to medical facility for definitive care
  • If etiology is exertional, American College Sports Medicine guidelines recommends no exercise for 7 days after event
 Complications
  • If patient does not respond quickly to cooling treatment, consider other etiologies of hyperthermia
    • infection/meningitis
    • thyroid storm
    • anticholinergic poisoning
    • delirium tremens

References

Please rate topic.

Average 5.0 of 3 Ratings

Questions (5)
Question locked
Sorry, this question is for
PEAK Premium Subscribers only
Upgrade to PEAK
Question locked
Sorry, this question is for
PEAK Premium Subscribers only
Upgrade to PEAK
Question locked
Sorry, this question is for
PEAK Premium Subscribers only
Upgrade to PEAK
Question locked
Sorry, this question is for
PEAK Premium Subscribers only
Upgrade to PEAK
Question locked
Sorry, this question is for
PEAK Premium Subscribers only
Upgrade to PEAK
EXPERT COMMENTS (11)
Private Note