Heat Stress

Incidence

The condition is most common in travellers from the temperate southern winter who journey into the tropics, particularly those who are out of condition and/or overweight.

While physical fitness can make one better able to cope with the heat and accelerate acclimatisation, Travelvax advises all travellers to take sensible precautions.

Symptoms

Symptoms of heat exhaustion include: headache, dizziness, nausea, fatigue and thirst. Treatment consists of rest and rehydration.

Prevention

Hydration is the key:

• Drink at least 500mL of water after rising in the morning.
• Always carry water with you and maintain a constant intake (up to 1 litre per hour if exercising/walking).
• Minimise coffee and alcohol intake because of their diuretic effect.

Passing light yellow urine several times a day is the best indicator of adequate hydration. Thirst is experienced when a person is approximately one litre dehydrated.

Add salt to the diet. Salt replacement drinks used in sporting activities are not the best source of water as they can actually slow water absorption. Dilute these by at least 1:4.

Twenty minutes of light to moderate exercise in the cooler part of the day facilitates acclimatisation.

Wear light, cotton clothing.

Treatment

Heat Exhaustion

The key to treatment is rehydration and rest. To treat:

• Start with sips of cool-cold water.
• Gradually increase up to 250mls each 15 minutes.
• 2-3 litres may be required to rehydrate (in 2-3 hours).

Evacuation for further treatment is not required after successful rehydration.

Heat Stroke

If not treated early, the next stage of heat exhaustion is Heat Stroke - a medical emergency. Changes in the level of consciousness, irritability, hallucinations and ataxia (unsteadiness in walking) are signs of Heat Stroke. Urgent evacuation to the nearest medical facility is required.

While waiting for medical assistance, begin treatment by:

• Getting the victim into shade.
• Cooling them down as quickly as possible by placing them under a cool shower, spraying them with water from a garden hose; sponge them with cool water; or wrapping them in a cool, wet sheet and fanning them.
• Monitoring their body temperature until it is below 38-39^oC.
• Giving them cool water or other non-alcoholic drinks. Heat stroke victims should NOT drink alcohol.
• Following up to ensure medical assistance arrives as soon as possible.

CHILDREN: Initially, treat a child as for heat exhaustion and seek urgent medical attention. Heat stroke puts enormous stresses on the body's circulation and requires expert, rapid treatment by a medical professional.