Heat-Related Illness Treatment

Initial Management

• Remove the person from the heat source and move them to a cool, shaded environment immediately, and have them lie down in a cool place, and remove excess clothing to facilitate cooling, as recommended by the American Heart Association 1
• Apply cooling methods such as cool water spray on the skin, and use commercial electrolyte-carbohydrate drinks, juice, or milk as appropriate fluids, as suggested by the American Heart Association 1
• Consider stretching, icing, and massaging painful muscles if heat cramps are present, and monitor for signs of progression to heat stroke, as recommended by the American Heart Association 1

Prognosis and Monitoring

• Heat exhaustion is a serious condition that can rapidly progress to potentially fatal heat stroke if not treated promptly and effectively, but the prognosis is generally good with proper treatment, as stated by the American Heart Association 1
• Measure core temperature using reliable methods, with a bladder catheter thermistor preferred when available, as recommended by the American College of Critical Care Medicine 2
• Rectal temperature measurement is recommended for a more accurate reading, particularly when needed, as suggested by the American College of Critical Care Medicine 2
• Assess for environmental exposure, as recommended by the American Heart Association 3
• Consider vitamin D deficiency as a contributing factor to temperature sensitivity, according to the British Journal of Dermatology guidelines 4

Prevention

• Prevent heat loss by layering clothing appropriately, covering the head and neck in cold environments, and using insulating materials, as recommended by the American Heart Association, similar to guidelines found in Circulation 3
• Maintain core temperature with high-calorie foods and warm drinks, as suggested by the American Heart Association, similar to guidelines found in Circulation 3
• Engage in physical activity in cold environments to generate heat, although the specific details are not provided in the article, and the strength of evidence for this is low, based on general medical knowledge 3
• Prevent heat exhaustion by proactive hydration before, during, and after heat exposure, activity modification based on environmental conditions, and appropriate clothing, as recommended by the British Journal of Sports Medicine 5

Diagnostic Workup

• Consider thyroid function tests, complete blood count, and vitamin D levels in the diagnostic workup, with the strength of evidence for these tests being moderate to high, based on general medical knowledge 4
• Perform a focused physical examination to identify potential infection sources and order specific tests based on clinical findings, as suggested by the American College of Critical Care Medicine 2
• Distinguish between infectious fever and heat-related illness, which is environmental or exertional in nature 2
• Autonomic function testing may be indicated in certain cases, although the specific details are not provided in the article, and the strength of evidence for this is low, based on general medical knowledge 3

Treatment

• Take immediate cooling measures for patients with heat exhaustion, including removing the patient from the heat source, applying ice packs to the neck, axillae, and groin, and using cold water immersion for severe cases (≥40°C/104°F), as recommended by the American Heart Association 1
• Continue cooling until the temperature reaches just under 39°C (102°F) 1
• Provide electrolyte-containing fluids for rehydration, with the following rates: adults 1.0-1.5L per hour, adolescents 1.0-1.5L (34-50oz) per hour, and children 9-12 years 100-250mL every 20 minutes, as suggested by the American Academy of Pediatrics 6
• Rehydrating with electrolyte-containing fluids can help prevent hyponatremia and treat heat-related dizziness, as recommended by the American Academy of Pediatrics and the American Heart Association 6, 7

High-Risk Populations

• Certain populations, including children, adolescents, elderly individuals, obese individuals, people with chronic diseases, individuals taking certain medications, and those with pre-existing cardiovascular conditions or multiple sclerosis, are at higher risk for temperature-related illnesses, and require special consideration and preventive measures, as recommended by the American Academy of Pediatrics and the American Heart Association 6, 8

Key Symptoms and Differences

• Heat exhaustion is characterized by inability to maintain blood pressure and sustain adequate cardiac output, resulting from strenuous exercise/activity, environmental heat stress, acute dehydration, and energy depletion, with a core temperature up to 40°C (104°F) but not higher, and normal mental status, as recommended by the American Academy of Pediatrics 6
• Key symptoms to assess include weakness, dizziness, nausea, syncope, headache, which are critical in distinguishing heat exhaustion from other conditions, with a focus on vital signs, including heart rate, blood pressure, respiratory rate, and rectal temperature 6
• The following table summarizes the key differences between heat exhaustion and heat stroke:

Follow-up and Education

• Monitor symptoms with a temperature and symptom diary, with the strength of evidence for this being moderate, based on general medical knowledge 4
• Regular follow-up with a healthcare provider is necessary to evaluate the effectiveness of interventions, as recommended by general medical guidelines, with the strength of evidence for this being high 3
• Gradual introduction to activity in heat over 10-14 days can help with acclimatization, and maintaining proactive hydration with electrolyte-containing fluids is essential 6
• Educate patients on the importance of activity modification based on environmental conditions and heat index, as well as wearing appropriate clothing, such as lightweight, breathable fabrics in hot environments 6
• No same-day return to activity is recommended for anyone experiencing heat exhaustion, and gradual return to normal activities should wait for complete symptom resolution, with medical clearance may be necessary before resuming strenuous activity, especially in severe cases, as recommended by the American College of Sports Medicine and the American Heart Association 5, 3