Management of Minor Heat-Related Illnesses
For most minor heat-related illnesses, supportive care is the mainstay of treatment (Table).
Miliaria Rubra
Infants with miliaria rubra typically improve once they are placed in a cool environment and their clothing is removed. In infants, lotions may contribute to sweat gland obstruction and should be used sparingly.13
Heat Edema/Heat Cramps
Similarly, heat edema generally improves once the child is removed from the hot environment and the extremities are elevated.14 Heat cramps are likely the result of fatigue and dehydration; therefore, these painful contractions often improve with rest, stretching, oral hydration, and removal from the hot environment. If cramps persist despite these measures, parenteral rehydration (20 mL/kg of normal saline) may be beneficial.15
Heat Syncope
Patients with orthostatic hypotension from heat syncope usually improve once they are resting in a cool environment and have been rehydrated. Pediatric oral rehydration with salt-containing fluids, such as commercial sports drinks, is safe; nonetheless, these patients may require intravenous (IV) rehydration with normal saline if orthostatic hypotension does not improve with oral rehydration alone.14
Heat Exhaustion
Differentiating heat exhaustion from heatstroke is of upmost importance because the treatment courses vary greatly. The difference in neurological status is the most effective way of differentiating the two diseases. All patients with slurred speech, ataxia, delirium, hallucinations, or seizure activity should be treated for presumptive heatstroke until proven otherwise (see “Management of Heatstroke” section).
Although children with heat exhaustion may have mild confusion, this tends to be transient and resolves with supportive care. Patients with heat exhaustion should stop exercising and be placed in a cool environment without excess clothing. Oral rehydration with salt-containing fluids is important, and most patients improve with these measures alone.
Children with apparent heat exhaustion who do not improve should be evaluated in the hospital setting, and laboratory studies should be obtained to evaluate for electrolyte abnormalities. Such patients typically warrant a 20 mL/kg IV bolus of normal saline. A complete neurological examination and a rectal temperature should be obtained on initial presentation.16
The evaluation of an overbundled infant with hyperthermia may be particularly challenging. Studies have demonstrated that it is possible for an infant to develop core temperature elevation if overbundled and placed in a warm environment.24 Nonetheless, it is important to address these patients with a broad differential diagnosis in mind, and always consider the possibility of sepsis. If the history and examination are consistent with hyperthermia secondary to heat exposure, a period of observation with supportive care may be a reasonable option. Infants should have a rectal temperature assessed every 15 to 30 minutes to monitor for improvement; if they improve with supportive care alone, a septic evaluation can be potentially avoided. Antipyretics will confuse the clinical picture and should be avoided in this situation.24
Management of Heatstroke
Significant morbidity and mortality are associated with heatstroke, and prompt recognition and initiation of therapy are required to prevent or minimize serious complications.22 As in any other life-threatening condition, the initial treatment of heatstroke requires support of the airway, breathing, and circulation. Patients are often neurologically unstable and cannot protect their airway, which should prompt endotracheal intubation. Children who are tachycardic and hypotensive should be resuscitated with normal saline prior to intubation if oxygenation and ventilation are maintained with supplemental oxygen alone. Most patients require at least 20 mL/kg of IV normal saline but many ultimately need up to 60 mL/kg.14 If blood pressure (BP) does not respond adequately to fluid resuscitation alone, vasopressors may be necessary. Seizure activity can be managed with IV benzodiazepines, such as lorazepam (0.1 mg/kg with maximum 4 mg per dose).14
Rapid cooling therapy is the mainstay of treatment for heatstroke and should be initiated as soon as the diagnosis is suspected, since morbidity and mortality correlates directly with the duration of hyperthermia. These measures are ideally started prior to arrival at the hospital. Evaporative cooling can be achieved in the field or ambulance with a cool water spray and air conditioning. Additionally, ice packs can be placed along the neck and axilla to augment rapid cooling measures and can be continued in the ED until the patient’s core temperature decreases to 101.4°F.25
Medications have a limited role in the treatment of heatstroke. Antipyretics such as acetaminophen and ibuprofen have no proven benefit and may exacerbate hepatic, gastrointestinal, clotting, and renal dysfunction.26 Benzodiazepines are helpful for seizure activity and may have a role in seizure prophylaxis. Dantrolene is not recommended for treating heatstroke as studies have not demonstrated a statistical improvement in cooling time, complications, or mortality.14 The use of chilled IV fluids instead of room-temperature fluids is not definitively supported in the literature.27