Notes – Hyperthermia/Heat Exposure

Hyperthermia/Heat Exposure

Patient Safety Considerations

  1. Consider use of physical securing devices [see Agitated or Violent Patient/Behavioral Emergency guideline] to protect vascular access sites.

Notes/Educational Pearls

Key Considerations

  1. Patients at risk for heat emergencies include neonates, infants, geriatric patients, and patients with mental illness
  2. Contributory risk factors may come from:
    1. Prescription and over-the-counter herbal supplements
    2. Cold medications
    3. Heart medications
    4. Diuretics
    5. Psychiatric medications
    6. Drug abuse
    7. Accidental or intentional drug overdose
  3. Heat exposure can occur either due to increased environmental temperatures or prolonged exercise or a combination of both
    1. Environments with temperature 90°F and humidity  60% present the most risk
  4. Heat stroke is associated with cardiac arrhythmias independent of drug ingestion/overdose
    1. Heat stroke has also been associated with cerebral edema
  5. Do not forget to look for other causes of altered mental status such as low blood glucose level, or, in the proper circumstances (e.g. endurance exercise events), consider exercise associated hyponatremia (EAH), especially in the patient with altered mental status, normal blood glucose, and normal temperature
  6. Controversy: shivering may occur while treating heat stroke
    1. It is uncertain how harmful shivering is to heat stroke patients
    2. Cooling should be continued until the above temperature and mental status goals are met
    3. Treat shivering as above
    4. Research does not demonstrate the value of one benzodiazepine over another in shivering patients
  7. Hyperthermia not from environmental factors has a differential that includes the following:
    1. Fever and delirium
    2. Hyperthyroid storm
    3. Delirium tremens (DTs)
    4. CNS lesion or tumor
    5. Adverse drug event: neuroleptic malignant syndrome, malignant hyperthermia
    6. Mental status changes without hyperthermia in the correct circumstances could be exercise associated hyponatremia
  8. There is no evidence supporting EMS utilizing orthostatic vital signs

Pertinent Assessment Findings

  1. Warning signs: fever, altered mental status
  2. Blood glucose level for AMS

Quality Improvement

Associated NEMSIS Protocol(s) (eProtocol.01)

  • 9914027 – Environmental – Heat Exposure/Heat Exhaustion
  • 9914029 – Environmental – Heat Stroke /Heat Exposure

Key Documentation Elements

  • Patient assessment includes all types of medication/drug use and detailed past medical history
  • Environmental assessment performed
  • Cooling interventions considered and implemented
  • Decision-making regarding securing devices
  • Decision-making regarding monitoring ABCs

Performance Measures

  • Blood glucose level obtained.
  • Fluids given for hypotension
  • Attempts to reduce core temperature
  • All decompensations during EMS care reviewed
  • EMS Compass Measures (for additional information, see http://www.emscompass.org)
    • Hypoglycemia-01: Treatment administered for hypoglycemia. Measure of patients who received treatment to correct their hypoglycemia
    • PEDS-03: Documentation of estimated weight in kilograms. Frequency that weight or length-based estimate are documented in kilograms

References

  1. Bouchama A, Knochel JP. Heat Stroke. NEJM. 2002;346(25):1978-88.
  2. Bouchama A, Dehbi M, Chaves-Carballo E. Cooling and hemodynamic management in heatstroke: practical recommendation. Crit Care Lond Engl. 2007;11(3):R54.
  3. The Futility of Orthostatic Measurements. Lifeinthefastlane.com. http://lifeinthefastlane.com/futility-orthostatic-measurements/. Published January 14, 2014. Accessed August 9, 2014
  4. Heled Y, Rav-Acha M, Shani Y et al. The “Golden Hour” for heatstroke treatment. Mil Med,
    2004 169(3)184-186
  5. Lipman G, Eifling K, Ellis MA, et. al. Wilderness Medical Society practice guidelines for the prevention and treatment of heat-related illness. Wilderness Environ Med. 2013;24(4):351-61.
  6. Vicario SJ, Okabajue R, Haltom T. Rapid cooling in classic heatstroke treatment: effect on mortality rates. Am J Emerg Med. 1986;4(5):394-8.