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cooler area and splash water with fanning, to enhance cooling. Oral rehydration is
indicated when fully alert. Assess the patient for injuries if a fall was associated with the
syncope.
C. Heat rash, (prickly heat, or miliaria) is an acute inflammatory disease of the skin seen
in humid regions following prolonged sweating. Sweat gland ducts become blocked with
keratinizing cells and accumulated sweat is forced through the duct walls, inciting
inflammation in adjacent soft tissue. Erythematous pruritic papules appear on trunk and
extremities, excluding hands and feet. Secondary infection may occur. In severe cases
heat tolerance is reduced due to decreased sweating. In the field, keep the affected areas
clean and limit exercise and heat exposure.
D. Heat exhaustion is caused by dehydration and intravascular volume depletion in a
thermally stressful environment. Symptoms and signs include: weakness, inability to
work, headache, mild confusion, nausea, faintness, anorexia, dyspnea and rapid pulse.
Skin may be warm or cool with sweating. The core temperature may be normal or
moderately elevated. In practice, the distinction between heat exhaustion and heat stroke
may be somewhat blurred. Should doubt exist then always err on the side of caution and
treat as per heat stroke (see below). Otherwise remove the patient to a cooler area, allow
to rest, and rehydrate orally, preferably with cold, lightly-salted water or an electrolyte
solution. The patient may benefit from cooling of the skin by wetting and fanning. When
the patient has fully recovered, the activity may continue. Depending on the extent of the
illness, recovery may take as long as 24 hours.
E. Heat stroke (both classical from exposure to heat and exertional from work in heat) are
true medical emergencies in which elevated core body temperature (above 105°F,
40.5°C, rectally) causes renal, hepatic, and nervous system damage. Persons at an
increased risk of heat stroke include those who are obese, unfit, unacclimatized, elderly,
acutely ill, dehydrated from vomiting or diarrhea; individuals with underlying medical
conditions, such as coronary heart disease, hyperthyroidism; and individuals on certain
medications, e.g., beta-blockers, stimulants, diuretics, or anticholinergics.
Skin may be dry or sweating preserved, especially in a fit person suffering
exertional heat stroke. Symptoms and signs include confusion, disorientation, bizarre
behavior, ataxia, tachycardia, tachypnea, and hot, red skin. Both heat stroke and heat
exhaustion may present as collapse in the face of a heat load - environmental heat,
metabolic heat from exercise, or a combination of both. Both may have altered
consciousness, elevated temperatures, and rapid pulse. Heat stroke is differentiated from
heat exhaustion by the presence of cardiovascular shock, persistent profound mental
status changes, and markedly elevated temperature. In heat exhaustion, mental status and
blood pressure normalize rapidly as in syncope, if the patient is recumbent in the shade.
Heat stroke has a high mortality rate. Whenever there is altered mental status and
elevated temperature, rapid cooling is essential and must be started in the field. Treatment
may include: 1) shading from direct sunlight and removal of clothing; 2) wetting with
tepid or cool water and fanning aggressively; 3) ice packs at the neck, armpits, and groin;
4) cold water immersion is the most efficient cooling method if possible; and 5) give
intravenous fluids if possible. If possible, check the rectal temperature every 5 to 10
