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Exertional heat illness in adolescents and adults: Management and prevention

Francis G O'Connor, MD, MPH, FACSM
Douglas J Casa, PhD, ATC, FNAK, FACSM, FNATA
Section Editors
Daniel F Danzl, MD
Karl B Fields, MD
Deputy Editor
Jonathan Grayzel, MD, FAAEM


Exertional heat illness (EHI) is among the leading causes of death in young athletes each year [1,2]. A report by the United States Centers for Disease Control (CDC) found that EHI occurs both during practice and competition and noted a disturbing trend of increasing incidence [3]; despite prevention efforts exertional heat stroke in the military continues to climb [4]. Clinicians who care for athletes, both young and old, and for others who exert themselves in the heat (eg, firefighters, soldiers, construction workers) need to be aware of the basic physiologic principles of thermoregulation, the spectrum of heat illness, strategies for prevention and treatment, and current guidelines for determining safe return to play or work.

The management and prevention of exertional heat illness are reviewed here. Thermoregulation and the clinical presentation and diagnosis of exertional heat illness are discussed separately, as are exercise-associated hyponatremia, nonexertional heat stroke, malignant hyperthermia, and heat illness in children. (See "Exertional heat illness in adolescents and adults: Epidemiology, thermoregulation, risk factors, and diagnosis" and "Exercise-associated hyponatremia" and "Severe nonexertional hyperthermia (classic heat stroke) in adults" and "Malignant hyperthermia: Clinical diagnosis and management of acute crisis" and "Neuroleptic malignant syndrome" and "Heat stroke in children" and "Heat illness (other than heat stroke) in children".)


Two critical observations inform the management of exertional heat stroke (EHS) and all types of severe heat illness [5-7]:

The severity of a heat illness may not be apparent during the initial presentation.

Morbidity and mortality are directly related to the duration of core temperature elevation.


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Literature review current through: Jul 2017. | This topic last updated: Nov 04, 2015.
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