Executive Summary
- Hyperthermia is characterized by an elevated core body temperature exceeding 38.5°C (101.3°F), resulting from an imbalance between heat production and dissipation. Unlike fever, which involves a regulated increase in the hypothalamic set point caused by pyrogenic cytokines, hyperthermia occurs without alteration of this set point.
- Pediatric populations have a decreased ability to recognize thirst. In addition, their limited mobility and inability to remove themselves from high-risk environments place them at higher risk. Children left in vehicles are at particularly high-risk of heat-related illnesses, since temperatures inside a closed vehicle rapidly rise to dangerous levels even when ambient temperature is only moderately high.
- Pediatric patients have physiological differences that make them more vulnerable to heat-related illnesses. Children absorb more heat because of their higher surface area-to-mass ratio, and they generate more metabolic heat with physical activity compared to adults because of their high basal metabolic rate. They also have decreased ability for heat dissipation because of their smaller absolute blood volume, limiting heat transfer from the body’s core to the skin surface. It also has been demonstrated that children produce less sweat compared to adults, and the core temperature at which sweating starts is higher.
- Heat syncope refers to a transient loss of consciousness with a relatively rapid return to normal neurologic baseline in the setting of exposure to heat. Patients with loss of consciousness in the context of heat exposure should be treated as heatstroke until proven otherwise. Treatment of heat syncope involves rehydration to replace fluid losses. Supine positioning with leg elevation above the level of the heart also can be helpful to increase blood flow back to the heart.
- Heat exhaustion occurs when the body is unable to adequately cool itself during prolonged exposure to high temperatures and humidity — but without the severe systemic dysfunction seen in heatstroke. Heat exhaustion results in a variety of symptoms, such as heavy sweating, weakness, dizziness, headache, nausea, and muscle cramps. It also can present with vital sign abnormalities, including hyperthermia and tachycardia.
- Early management of heat exhaustion focuses on removing the child from heat sources, initiating active cooling, and providing oral hydration if the child is alert and able to drink. Fanning can be an effective method that increases efficiency of sweating/evaporation to help cool the body. Ice packs or cold, wet cloths also can be applied to the armpits, groin, or forehead.
- Heatstroke is characterized by a core body temperature typically exceeding 40°C (104°F) and accompanied by central nervous system dysfunction.
- The cornerstone of heatstroke management is rapid reduction of core body temperature to prevent ongoing cellular injury and multiorgan dysfunction. Initial evaluation focuses on airway, breathing, and circulation (ABC). After rapid evaluation of ABCs, the next step in management is initiating rapid cooling. Evaporative cooling should be achieved by spraying patients with tepid water and fanning the patient, preferably with high-flow fans. In adult studies, evaporative cooling has been shown to have cooling rates close to 0.15°C (0.27°F) per minute. In addition to evaporative cooling, cooling blankets and ice packs can be used. Ice packs should be applied to the groin, torso, neck, and axilla regions. Cold water immersion may also be used and is achieved by removing insulating clothing and equipment and submersing the patient’s trunk and extremities in a bath of ice water or the coldest water available.
This summer has been hot and, unfortunately, many pediatric patients have sustained heat-related conditions. Providers need to be ready to quickly recognize heat-related illnesses and institute prompt and life-saving care to give each patient the chance for the best outcome. The authors comprehensively review common and life-threatening, heat-related illnesses with an emphasis on evidence-based care.
— Ann M. Dietrich, MD, FAAP, FACEP, Editor
By Daniel Migliaccio, MD, FPD, FAAEM
Introduction
In the United States, weather-related events were linked to 1,423 pediatric deaths from 2001 to 2021, underscoring the significant effects of environmental hazards on children.1 The World Health Organization recently identified heat stress as the leading cause of weather-related mortality, with the frequency and intensity of extreme heat events increasing as a consequence of climate change.2 Heat-related illness encompasses a spectrum of conditions that result from the body’s inability to dissipate heat effectively. Pediatric patients possess unique behavioral and physiological characteristics, such as reduced thermoregulatory capacity, higher metabolic heat production, and limited mobility because of age, that increase their susceptibility to these conditions. For emergency medicine providers, recognizing these vulnerabilities, ensuring early diagnosis, and initiating prompt treatment are critical to preventing rapid clinical deterioration, morbidity, and death.
Epidemiology
Environmental exposures contribute substantially to pediatric morbidity and mortality worldwide. The frequency of extreme heat events has increased over the last five decades — in both the United States and globally — largely because of climate change.3 The United Nations Children’s Fund estimates that 559 million children already are being exposed to high heat wave frequency, and, by 2050, this number is expected to rise to 2 billion.4
Between 2000 and 2019, approximately 489,000 heat-related deaths occurred globally each year, with children representing a vulnerable subset of this population.5 Among teenage athletes, heat illness is the third major cause of death behind traumatic and cardiac causes.6,7 Pediatric heat-related emergency department visits increased by 170% from 2012 to 2023, rising from 4.3 to 11.6 encounters per 10,000 total ED visits.8 Despite the substantial burden, pediatric-specific environmental risks remain underrepresented in public health initiatives and medical education. As heat wave frequency continues to rise, early identification, effective prevention, and timely treatment of pediatric heat-related illness will be essential to reducing morbidity and mortality in this at-risk population.
Epidemiology
The normal core body temperature is generally accepted to be between 36°C to 38°C. Hyperthermia is characterized by an elevated core body temperature exceeding 38.5°C (101.3°F), resulting from an imbalance between heat production and dissipation. Unlike fever, which involves a regulated increase in the hypothalamic set point caused by pyrogenic cytokines, hyperthermia occurs without alteration of this set point. Consequently, thermoregulatory mechanisms fail to adequately dissipate heat, leading to an uncontrolled rise in core temperature that can result in cellular injury and systemic dysfunction.9,10 Antipyretics are not effective in cases of elevated temperature caused by environmental/external heat exposure, given this key difference in mechanism underlying the hyperthermia. Table 1 summarizes the key differences between fever and hyperthermia.
Table 1. Fever vs. Hyperthermia |
Fever
Hyperthermia
|
Etiology
The body has several mechanisms to compensate for hyperthermia. Evaporation is the primary mechanism of heat loss, but this becomes ineffective above a relative humidity of 75%.11 The other methods of heat dissipation include radiation (emission of infrared electromagnetic energy), conduction (direct transfer of heat to an adjacent, cooler object), and convection (direct transfer of heat to convective air currents). These methods of heat dissipation are less effective when the temperature of the environment exceeds skin temperature (typically 35°C/95°F).11
Ambient temperature often is the most cited and accessible measure of environmental heat, but it does not adequately capture the physiological stress imposed on the human body. The wet bulb globe temperature (WBGT) is a more comprehensive index that integrates ambient temperature with humidity, wind speed, and solar radiation.12 These additional variables are critical, since high humidity impairs evaporative cooling, direct sun exposure accelerates heat gain, and limited airflow reduces convective heat loss. For example, a seemingly moderate ambient temperature can still pose significant danger in humid or high ultraviolet radiation environments, particularly for children, whose thermoregulatory mechanisms are less efficient than those of adults. Therefore, WBGT has become the standard metric used by occupational, military, and athletic organizations to guide activity modification and prevent heat-related illness.12 For medical providers, understanding WBGT in contrast to ambient temperature is important when counseling caregivers, schools, and sports programs, since reliance on ambient temperature alone can underestimate true heat risk in pediatric populations.
Infants and young children are particularly vulnerable to heat-related illnesses because of their behavioral and physiological differences from adults. Pediatric populations frequently engage in outdoor play during peak heat hours and have a decreased ability to recognize thirst. In addition, their limited mobility and inability to remove themselves from high-risk environments place them at higher risk. Children left in vehicles are at particularly high-risk of heat-related illnesses, since temperatures inside a closed vehicle rapidly rise to dangerous levels even when ambient temperature is only moderately high.13 In 2024, 39 U.S. children died of heatstroke from being trapped or left in a vehicle, up 35% from 2023.14
The pediatric population also has physiological differences from adults that make them more vulnerable to heat-related illnesses. Children absorb more heat because of their higher surface area to mass ratio, and they generate more metabolic heat with physical activity compared to adults because of their high basal metabolic rate.15 They also have decreased ability for heat dissipation because of their smaller absolute blood volume, limiting heat transfer from the body’s core to the skin surface.16 It also has been demonstrated that children produce less sweat compared to adults, and the core temperature at which sweating starts is higher.17,18 All of these factors predispose pediatric patients to heat illness and are important for providers treating pediatric patients to understand.
Types of Heat-Related Illnesses
Exercise-Associated Muscle Cramps
Exercise-associated muscle cramps (EAMC) are a common cause of acute muscle pain and disability among pediatric patients, most commonly athletes. Previously referred to as heat cramps, current literature has shifted to exercise-associated muscle cramps instead, since the symptoms and presentation do not directly correspond to an elevated body temperature.19 The etiology is multi-factorial and thought to involve dehydration, electrolyte imbalances, and muscle fatigue. Cramps often occur in larger muscle groups (e.g., lower extremities). Treatment focuses on rest, hydration, electrolyte replacement, muscle massage, and stretching.20
Heat Rash (Miliaria)
Heat rash (miliaria) occurs because of occlusion of sweat glands, causing sweat-filled vesicles to develop under the skin. Miliaria is more common in hot and humid environments, and infants and children are at higher risk because of the immaturity of their eccrine ducts.21
Miliaria presents in three main forms based on the depth of sweat gland obstruction:
- Miliaria crystallina is the mildest and most common form in neonates. It affects the superficial stratum corneum and appears as small, clear vesicles mostly on the face and trunk.
- Miliaria rubra involves deeper epidermal obstruction. It presents as erythematous, pruritic macules and papules that may progress to pustular lesions.
- Miliaria profunda is the most severe, affecting the dermal-epidermal junction. It is characterized by larger, asymptomatic white vesicles.
Management centers on preventing sweat duct blockage by reducing sweating, avoiding heat exposure, and removing occlusive materials. Treatment varies slightly based on the type of miliaria. Miliaria crystallina usually is self-limiting. Miliaria rubra responds to topical corticosteroids, with topical antibiotics added if pustules develop. There are limited data on therapies for miliaria profunda, but some studies show positive outcomes with oral isotretinoin and topical lanolin.22
Heat Edema
Heat edema is a benign, self-limited peripheral swelling that occurs in individuals after exposure to hot environments. Risk factors include age and poor acclimatization to heat. It often occurs in the elderly and is less frequent in pediatric patients, but it is still an important diagnosis for pediatric providers to be aware of. Edema secondary to heat exposure occurs when interstitial fluid accumulates in dependent extremities because of cutaneous vasodilation and sodium/water retention, leading to an increased hydrostatic pressure. This results in vascular leak, which causes pooling of interstitial fluid in those dependent extremities.23 Clinically, it presents as non-pitting or pitting edema of the hands, feet, or ankles. Notably, there is an absence of pain, erythema, or systemic symptoms. This is important in distinguishing heat edema from more serious etiologies, such as heart failure, deep vein thrombosis, or cellulitis.
Management consists of removal from the hot environment, limb elevation, compression stockings, and reassurance. Most importantly, diuretics are not effective in edema caused by heat exposure and can worsen patient presentation, since patients frequently are volume depleted in the setting of heat-related edema.24 Symptoms typically resolve within several days with supportive care. Patients should be educated about acclimatization and avoidance of prolonged standing in heat for prevention of future occurrences.
Heat Syncope
Heat syncope refers to a transient loss of consciousness with a relatively rapid return to normal neurologic baseline in the setting of exposure to heat.23 A rise in body temperature leads to sympathetic cutaneous vasodilation, which promotes sweating but also results in a reduction in the intra-vascular volume, which can lead to syncope.25 Risk factors include prolonged standing, dehydration, medication side effects (less common in pediatric patients), and coexisting medical conditions that reduce cardiac output. Patients should return to baseline and recover rapidly after supportive measures are taken.
Patients with loss of consciousness in the context of heat exposure should be treated as heatstroke until proven otherwise. Treatment of heat syncope involves rehydration to replace fluid losses. Supine positioning with leg elevation above the level of the heart also can be helpful to increase blood flow back to the heart. Orthostatic vital sign measurements can be useful to monitor for adequate fluid replacement in addition to evaluating for resolution of symptoms during positional changes.26 If patients are not recovering as expected, providers should consider more life-threatening etiologies such as heatstroke, or other diagnoses unrelated to heat.
Heat Exhaustion
Heat exhaustion represents an important clinical condition, particularly in pediatric populations because of their increased vulnerability to heat stress and the potential for progression to more severe heat-related illnesses if it is not promptly recognized and managed. Heat exhaustion occurs when the body is unable to adequately cool itself during prolonged exposure to high temperatures and humidity — but without the severe systemic dysfunction seen in heatstroke. Heat exhaustion results in a variety of symptoms, such as heavy sweating, weakness, dizziness, headache, nausea, and muscle cramps.26 It also can present with vital sign abnormalities, including hyperthermia and tachycardia.
Early management focuses on removing the child from heat sources, initiating active cooling, and providing oral hydration if the child is alert and able to drink. Cooling of the body can occur in multiple different ways. In the initial Emergency Medical Services setting or in an austere environment, fanning can be an effective method that increases efficiency of sweating/evaporation to help cool the body.27 Ice packs or cold, wet cloths also can be applied to the armpits, groin, or forehead to help with cooling as well. Continuous monitoring of vital signs and mental status is essential to prevent progression to more serious disease (heatstroke).27 Most cases of heat exhaustion will improve if the appropriate interventions are performed, and most patients do not require emergent evaluation or hospitalization if their symptoms are improving.
Heatstroke
Heatstroke is the most severe form of heat-related illness. It is characterized by a core body temperature typically exceeding 40°C (104°F) and accompanied by central nervous system (CNS) dysfunction. It represents a medical emergency requiring immediate recognition and intervention to prevent multiorgan failure and death. There are two broad categories of heatstroke — classic and exertional.
Classic vs. Exertional Heatstroke
Classic heatstroke typically occurs in vulnerable populations, such as young children or the elderly. It occurs because of prolonged exposure to high environmental temperatures and often develops gradually as the body fails to dissipate heat effectively.28 Children who are too young to walk may be predisposed to classic heatstroke, since they cannot remove themselves from the heat source. Another important consideration in the pediatric population is classic heatstroke caused by prolonged time in a hot vehicle.
Exertional heatstroke, on the other hand, primarily affects healthy, active individuals — such as athletes or laborers — during intense physical exertion in hot environments. It results from the combined effects of internal heat production and environmental heat load, leading to a rapid onset of symptoms.28 While treatment remains the same regardless of the type of heatstroke, it is important for pediatric providers to understand that children are vulnerable to both types, given their age and outdoor activities (e.g., sports).
Pathophysiology
In heatstroke, the body’s thermoregulatory mechanisms are overwhelmed by excessive endogenous heat production (exertional heatstroke) and/or impaired heat dissipation because of environmental heat exposure (classic heatstroke). This results in a critical rise in core body temperature, typically exceeding 40°C or 104°F. Hyperthermia causes direct cellular injury through multiple mechanisms, including protein denaturation, disruption of cellular membranes, mitochondrial dysfunction, and impaired enzymatic activity, ultimately leading to cell death. The body produces a systemic inflammatory response with release of pro-inflammatory cytokines (ex: interleukin [IL]-1, IL-6, tumor necrosis factor-alpha), resulting in endothelial dysfunction, increased vascular permeability, and coagulopathies.29 These effects lead to multiorgan dysfunction, including CNS impairment, which characterizes the severity of heatstroke.30,31 The combination of cytotoxicity, inflammation, and vascular dysregulation contributes to multiorgan dysfunction affecting the central nervous system, kidneys, liver, gastrointestinal tract, and cardiovascular system. CNS involvement manifests as delirium, seizures, ataxia, or coma and is the hallmark of heatstroke and a key determinant of prognosis.31 Additional complications may include rhabdomyolysis, acute kidney injury, hepatocellular injury, and arrhythmias, emphasizing the urgency of rapid recognition and aggressive cooling interventions.
Diagnosis
Diagnostic criteria for patients with heatstroke includes elevated core temperature (≥ 40°C or ≥ 104°F) and CNS dysfunction in the context of environmental heat exposure. In the emergency department setting, patients may arrive without this elevation in temperature if prehospital care initiated cooling measures. Therefore, CNS dysfunction should be the main diagnostic criterion used in identifying patients with heatstroke.32 In children specifically, CNS dysfunction most frequently presents as seizures, hallucinations, ataxia, dysarthria, or coma. Tachycardia and tachypnea are common vital sign abnormalities in patients with heatstroke, and a quarter of patients are hypotensive.33 The most common method for obtaining core temperature in pediatric patients is through a rectal thermometer. Oral, axillary, and tympanic membrane temperatures are unreliable and should not be used.34
While this review focuses on heatstroke, it is important to consider a broad differential diagnosis in children presenting with symptoms of heatstroke. Clinicians may not have the full history of environmental exposure, and there are several other medical conditions that can coexist or mimic heatstroke in children. Sepsis, especially meningitis, can cause high fever with altered mental status. However, typically fever does not exceed 41°C (105.8°F).35 Traumatic brain injuries and CNS conditions also can present with fever and altered mental status because of neurogenic fever.36 In these patients, the altered mentation almost always will precede the temperature dysregulation, differentiating it from heatstroke. Toxins are another important mimic of heatstroke. Drug-related causes of seizures and hyperthermia can include cocaine, methamphetamine, amphetamine, 3,4-methylenedioxymethamphetamine (ecstasy), salicylates, and anticholinergic agents.
Work-Up
Patients with heatstroke require laboratory tests to evaluate for end-organ damage and signs of coagulopathies or rhabdomyolysis. The recommended tests to obtain in pediatric patients presenting with findings concerning for heatstroke include:37
- point-of-care glucose testing;
- complete blood count;
- comprehensive metabolic panel;
- prothrombin time/international normalized ratio and partial thromboplastin time;
- blood gas (venous or arterial);
- serum creatine kinase (CK); and
- urinalysis to evaluate myoglobinuria.
In classic heatstroke, a respiratory alkalosis predominates, whereas exertional heatstroke also may have concomitant lactic acidosis. Electrolyte derangements often are present in both types of heatstroke and can include hypocalcemia, hyperphosphatemia, and hyperkalemia (reflecting the muscle breakdown that occurs). Rhabdomyolysis is more common in exertional than classic heatstroke, with a higher elevation of CK markers reported.37
In classic heatstroke, aspartate aminotransferase and alanine aminotransferase elevations are the most common lab abnormalities reported.37 Bicarbonate levels in patients with heatstroke often are < 20 mmHg.33
Heatstroke Management
The cornerstone of heatstroke management is rapid reduction of core body temperature to prevent ongoing cellular injury and multiorgan dysfunction. Initial evaluation focuses on airway, breathing, and circulation (ABC).
Airway and breathing. Children with heatstroke often require basic or advanced airway management because of their altered mental status. In patients requiring intubation, there have been discussions regarding rocuronium vs. succinylcholine for paralytics in heatstroke patients. Rocuronium is a non-depolarizing agent, and it is theorized that use of a non-depolarizing agent may avoid heat generation caused by fasciculations and reduce metabolic heat generation, given its longer duration of neuromuscular blockade. However, there is no clear evidence that supports the recommendation of rocuronium in favor of succinylcholine in this patient population, so provider discretion is recommended.38
Circulation. Rapid intravenous access through peripheral or central access is important for resuscitation of patients with heatstroke. Fluid resuscitation for hypotensive patients should start with an initial infusion of 20 mL/kg to 40 mL/kg of isotonic crystalloid. Additional fluids can be given, and many children with exertional heatstroke may require 60 mL/kg or more.30 Because of the decrease in systemic vascular resistance associated with heatstroke, there should be a low threshold to initiate vasopressor therapy in patients who are not responding to fluid resuscitation.
Disability. Altered mental status in heatstroke should resolve with normothermia and improvement in tissue perfusion. In patients who present with seizures, treatment with benzodiazepines is indicated.
Rapid cooling. After rapid evaluation of ABCs, the next step in management is initiating rapid cooling. The risk of morbidity and mortality from heatstroke increases with duration of hyperthermia, so rapid cooling is essential to treatment.39,40 There are several different methods for cooling outlined in the Table 2, many of which can be initiated in the prehospital setting.
Table 2. Summary of Rapid Cooling Methods for Heatstroke |
Ice Packs or Cool/Wet Towels
Evaporative Cooling
Cold Water Immersion
Invasive Cooling
|
In a prehospital setting with limited resources, if there is difficulty obtaining core temperature or if core temperature is < 40°C, cooling therapies should be initiated if suspicion for heatstroke is high. For the emergency department clinician, it is important to be aware that cooling measures may have been initiated already by prehospital providers. Therefore, a patient arriving with cool skin and normal core temperature on arrival should still be treated aggressively based on initial presentation and high index of suspicion.41
Evaporative cooling should be achieved by spraying patients with tepid water and fanning the patient, preferably with high-flow fans. In adult studies, evaporative cooling has been shown to have cooling rates close to 0.15°C (0.27°F) per minute.42 In addition to evaporative cooling, cooling blankets and ice packs can be used. Ice packs should be applied to the groin, torso, neck, and axilla regions.43
Cold water immersion is achieved by removing insulating clothing and equipment and submersing the patient’s trunk and extremities in a bath of ice water or the coldest water available. There are several options for cold water immersion, including a plastic sheet or tarp covered in ice and water added to form a slurry. A body bag may be the most accessible item to use in the emergency department and can help contain the patient, ice, and water.44 One important component of initiation of cold water immersion is early activation of the dining services, since they can provide ice in large quantities.
Several emergency departments have developed protocols for cold water immersion to standardize the process. An example protocol from the University of North Carolina at Chapel Hill’s emergency department. (See Table 3.) This protocol was developed by Daniel Willner with data from a recent article published in the Annals of Emergency Medicine.45
Table 3. Emergency Department Heatstroke/Cold Water Immersion Protocol |
Indication
Equipment
Location: Based on Patient Acuity and Monitoring Needs
Setup/Breakdown
Patient Care
|
Source: University of North Carolina at Chapel Hill |
Cold water immersion can have cooling rates up to 0.20°C per minute, which is greater than the cooling rate of evaporative cooling. It is important to note that pediatric patients may not tolerate cold water immersion as well as adult patients, and it may cause increased agitation and combativeness.36 Adjunct medications to help with shivering during cooling include intravenous benzodiazepines (e.g., midazolam, lorazepam). Preventing shivering is important to avoid endogenous heat production, which can worsen hyperthermia.
In patients who fail rapid cooling by the previously mentioned measures, more invasive measures, such as extra-corporeal membrane oxygenation (ECMO) or insertion of intravenous cooling catheters, can be considered and have well-established efficacies. However, they do require additional time for insertion of central venous catheters, and alternative methods should be initiated while prepping and activating resources for more invasive cooling measures.46
Termination of cooling methods is an important concept for pediatric emergency clinicians to understand, since rectal temperature can lag behind the drop in core temperature at the hypothalamus.47 The general consensus in pediatric populations with heatstroke is to discontinue cooling methods when rectal temperature reaches approximately 38°C (100.4°F) to prevent overshoot hypothermia.48,49
All patients with heatstroke should be admitted to a pediatric critical care unit. In settings where an intensive care unit is not available, patients should be transferred after appropriate resuscitation.
Prevention
Preventing pediatric heatstroke requires a comprehensive strategy that addresses environmental, behavioral, and clinical risk factors. Pediatric emergency physicians play an important role in counseling caregivers on risk reduction strategies and early recognition of heat-related illness. In the pediatric patient population specifically, prevention should target education surrounding children in vehicles and athletes, since these are high-risk populations.
Children in Vehicles
In 2024, 39 children died of heatstroke from being trapped or left in a vehicle, up 35% from 2023.14 On average, 37 children younger than 15 years of age die each year from heatstroke after being left in a vehicle.50 Caregivers may not plan to be away from the vehicle for very long, but in just 10 minutes, a car’s temperature can rise by up to 20°F.51 Cracking windows or parking in the shade offers minimal protection, since vehicle interiors can still reach dangerously high temperatures in a short period of time. Vehicles also can reach high interior temperatures even if the outside temperature is relatively mild, as low as 57°F.51
As clinicians, recognizing this high-risk population and educating caregivers about the dangers of vehicle-related heat illness and strategies for prevention can play a critical role in reducing morbidity and mortality. Caregivers should be warned to never leave a child unattended in a vehicle. A practical method to reduce this risk is the “look before you lock” approach, where a caregiver places a personal item, such as a purse or bag, in the backseat to prompt a visual check before exiting the vehicle.14 Counsel caregivers to always keep their cars locked when they are parked, since one in four vehicle-related heat deaths occur when a child mistakenly locks themselves inside.51
Athletes
Among teenage athletes, heat illness is the third major cause of death — behind traumatic and cardiac causes.6,7 If children are planning to exercise or play while it is hot outside, there are several preventive measures that can be taken. Core preventive measures include maintaining adequate hydration before and during physical activity and incorporating frequent rest periods in shaded or air-conditioned environments during heat exposure. If possible, avoid workouts or practice at times when the sun is the hottest (usually middle of the day). Children should wear loose, light-weight, and light-colored clothing and stay hydrated.52 Younger children may need more frequent, structured hydration, since their reduced thirst sensation often prevents them from drinking adequately on their own.
As mentioned, WBGT can be a more accurate, comprehensive measure of heat stress and may be beneficial to use in athletes participating in high-intensity training sessions or athletic events. Many athletic and school-based organizations have adopted WBGT-based guidelines, adjusting outdoor activities based on WBGT. An example WBGT guideline from the National Athletic Trainers’ Association is shown in Table 4.53
Table 4. Wet Bulb Globe Temperature Thresholds and Recommended Activity Modifications | |
Indication | Recommended Activity Modifcation |
< 27.8°C (< 82°F) |
|
27.8°C-30.5°C (82°F-86.9°F) |
|
30.5°C-32.2°C (87°F-89.9°F) |
|
32.2°C-33.3°C (90°F-92°F) |
|
> 33.4°C (> 92.1°F) |
|
Medications
Certain medications can increase the risk of heat-related illness by altering thermoregulation or producing side effects that impair the body’s ability to dissipate heat.54 While pediatric patients generally are on fewer medications than adults, it is important for providers to recognize high-risk agents in this population. These include non-selective antihistamines (e.g., diphenhydramine), stimulants (e.g., methylphenidate for attention-deficit/hyperactivity disorder), antipsychotics, anticholinergics, selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), and diuretics.55,56
Diuretics pose a particular risk because they can reduce thirst sensation and increase the likelihood of dehydration through fluid loss. Antipsychotics, anticholinergics, and stimulants may interfere with central thermoregulation, while SSRIs, SNRIs, and TCAs can impair sweating and compromise the body’s natural cooling mechanisms.
Heat exposure also can affect certain medications directly. For example, albuterol inhalers may be damaged by heat, potentially causing them to burst, and EpiPens may malfunction or deliver a suboptimal dose of epinephrine when exposed to high temperatures.55 Physicians should review medications with caregivers and educate them about which agents place children at higher risk for heat-related illness, as well as proper storage precautions to maintain medication efficacy.
Conclusion
Heat-related illnesses in pediatric patients are increasing in frequency and emergency departments visits with the increase in high temperatures secondary to climate change. Heat-related illnesses range from mild, self-limiting conditions, such as heat rash, to life-threatening emergencies, such as heatstroke. (See Table 5). Early recognition and targeted intervention are essential to preventing morbidity and mortality and are especially important in the pediatric population given the unique physiologic vulnerabilities of children to heat stress.
Table 5. Summary of Heat-Related Illnesses |
Exercise-Associated Muscle Cramps
Miliaria (Heat Rash)
Heat Edema
Heat Syncope
Heat Exhaustion
Heat Stroke
|
Emergency department clinicians play a pivotal role in initiating timely cooling strategies, preventing progression of disease, and delivering appropriate supportive care. Heightened awareness, caregiver education, and integration of preventive strategies into community and school-based programs can further reduce the burden of these conditions. Continued research is warranted to refine pediatric-specific diagnostic criteria, improve evidence-based management protocols, and, ultimately, enhance both acute care and prevention efforts in this at-risk population.
Daniel Migliaccio, MD, FPD, FAAEM is a clinical associate professor, division director of emergency ultrasound, ultrasound fellowship director, Department of Emergency Medicine, University of North Carolina at Chapel Hill.
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This summer has been hot and, unfortunately, many pediatric patients have sustained heat-related conditions. Providers need to be ready to quickly recognize heat-related illnesses and institute prompt and life-saving care to give each patient the chance for the best outcome. The authors comprehensively review common and life-threatening, heat-related illnesses with an emphasis on evidence-based care.
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