The temperatures are rising, and school sports are starting long practices in all kinds of weather. During intense exercise, people can lose up to 1.5 liters of fluid per hour. Summer is prime time for pediatric patients to sustain heat-related illnesses, and these patients may present to the emergency department in some distress.
Defining the components of and differences among heat-related illnesses is quite important. While only heat stroke is a true medical emergency, the following is a breakdown of the three most common heat-related illnesses that present to the emergency department:
Heat Cramps
Heat cramps are characterized by sudden and intense cramping in the muscles, usually in conditioned athletes, that occurs after the exercise is completed. These patients have typically supplemented their water losses but not their salt losses, so the cramping is likely due to the electrolyte imbalance. Laboratory data may reveal hyponatremia and hypochloremia with a normal to mildly elevated BUN.
Treatment for heat cramps:
These cases are usually not severe; giving fluids and salted foods will typically help resolve the symptoms. A fluid bolus with normal saline may occasionally be indicated with severe cramping.
Heat Exhaustion
Heat exhaustion usually occurs in less conditioned athletes during times of hot weather and after vigorous and/or prolonged exercise. It may be due to either poor water or poor salt replacement. The patient’s temperature will usually be below 102.2˚F (39˚C), and they will usually exhibit significant weakness, headache, and tachycardia along with hypotension or orthostatic hypotension. You may also see vomiting and/or GI disturbances. Lab values will be dependent on whether the heat exhaustion is from a predominance of salt depletion or water depletion.
Treatment for heat exhaustion:
If secondary to water depletion, treatment is fluid and rest in a cool environment. If secondary to salt depletion, in addition to resting in a cool environment, the patient should be given fluids with sufficient sodium. In patients with more severe symptoms, IV fluids with normal saline or lactated ringers may be indicated. Hypotonic fluids should be avoided.
Heat Stroke
Heat stroke usually occurs in patients who are either very old or very young. We typically hear about the infant left in the hot, closed car. Heat stroke can also occur with vigorous exercise, especially during heat waves; in fact, heat stroke is one of the leading causes of preventable death in sports. This is considered to be a true medical emergency, as these patients have profound hyperthermia; sweating may have already stopped. These patients will have varying degrees of CNS dysfunction ranging from headache to confusion to loss of consciousness. The patient’s skin will characteristically be hot, and they will exhibit varying degrees of circulatory decompensation.
Treatment for heat stroke:
Treatment should be directed at lowering the body temperature with vigorous supportive care that may range from seizure control to airway control to addressing rhabdomyolysis and renal damage. The patient will likely need intravenous fluids, but severe dehydration is not mandatory for the patient to have suffered from heat stroke. As noted, the body temperature should be lowered actively; in addition to placing the patient in a cool environment, use ice packs to the groin, neck and axilla. Monitoring of cardiac function and circulatory compromise is critical, as the patient can experience arrhythmias from being too heated as well as arrhythmias during the cooling process.
What's the risk with Pediatric Heat-Related Illnesses?
Delayed diagnosis and treatment of heat stroke can result in acute injury to the liver, kidney and lungs; permanent damage to the central nervous system; and death. Everyone involved in the training and care of children, including coaches, trainers, teachers, EMS personnel and clinicians, should be focused on efforts to prevent this severe condition; they must be tuned in to the early recognition and aggressive treatment of heat stroke in children.
References:
- Fleisher; Ludwig. Textbook of Pediatric Emergency Medicine, 4th Lippincott Williams and Wilkins. 200, 953-955.
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