Heat exhaustion

Background

Results from exposure to excessive heat or exposure to extreme temperature for prolonged period of time.

  • Can result from exposure to heat wave
  • Predicted to increase due to increasing climate temperatures.

Etiology[1]

  • Occurs via water depletion or sodium depletion or combination
  • Water depletion occurs in elderly and persons working in hot environments
  • Salt depletion occurs when fluid losses are replaced with hypotonic solutions

Clinical Features[2]

Known heat exposure with temperature 37-40C with:

Differential Diagnosis

Environmental heat diagnoses

Evaluation

Workup

  • Evidence of hemoconcentration
  • May be hyponatremic, isotonic or hypernatremic
    • Depending on ratio of fluid and electrolyte loss to intake

Diagnosis

  • Typically a clinical diagnosis.

Treatment[3]

  1. Removal from heat-stressed environment
  2. Volume and electrolyte repletion
    • Oral versus IV depending on severity
  3. Aggressive cooling to 39C if patient does not respond to 30min of fluid replacement

Disposition[4]

  • Majority of patients can be discharged
  • Consider admission in patients with CHF or severe electrolyte disturbances

Complications

See Also

References

  1. Waters T. Heat Emergencies In: Tintinalli's Emergency Medicine: A Comprehensive Study Guide. 7th ed. McGraw Hill Medical. 2011: 1339
  2. Waters T. Heat Emergencies In: Tintinalli's Emergency Medicine: A Comprehensive Study Guide. 7th ed. McGraw Hill Medical. 2011: 1339
  3. Waters T. Heat Emergencies In: Tintinalli's Emergency Medicine: A Comprehensive Study Guide. 7th ed. McGraw Hill Medical. 2011: 1339
  4. Waters T. Heat Emergencies In: Tintinalli's Emergency Medicine: A Comprehensive Study Guide. 7th ed. McGraw Hill Medical. 2011: 1339