Heat Exhaustion (HB)

Any time we produce more heat than we can tolerate or we absorb heat from high environmental temperatures, we are experiencing a heat challenge. An unchecked heat challenge will eventually lead to heat exhaustion or heat stroke.

It used to be thought that heat exhaustion was entirely a dehydration problem, but it is not. Many factors contribute to heat exhaustion–it is a continued heat challenge without dissipating heat efficiently.

Heat exhaustion can be caused by:

• Overexertion,
• Dehydration,
• Lack of acclimatization to the environment,
• Pre-existing medical condition

Prevention

You can prevent heat exhaustion by reducing the workload, protecting from the hot environment, and staying hydrated.

Signs and Symptoms

The patient may complain of weakness or dizziness. The patient’s skin may be pale or flushed, cool or warm and wet or dry–so you really cannot use the skin as a diagnostic tool here. The patient may also have cramping.

You may notice vital signs consistent with volume shock–elevated heart rate, elevated respiratory rate, and decreased urine output. The cause for these symptoms is a decrease in fluid volume as the patient’s body has attempted to cool itself through the evaporation of sweat.

There may be slight mental status changes, but these changes will be localized to the “awake” status. The patient may be lethargic or less active.

Treatment

Treatment of heat exhaustion is the same as prevention–reduce the workload, protect from the hot environment, and hydrate the patient.