Getting on top of the heat

Get on top of the heat.

Sticky situation: Keeping well hydrated is a key factor in minimising heat stress incidents in the Army. Photos by AB Kade Rogers, Navy newspaper

By the time you start sweating, you may already be dehydrated. Pte John Wellfare looks at heat illness.

The ADF provides detailed documentation covering the identi.- cation and management of heat illness. This information has been taken directly from ADF First Aid doctrine.

Know your enemy

Understanding how to deal with heat illness, according to the experts, is all about understanding how the body’s own cooling system works.

The human body has a number of built-in methods for reducing heat, of which evaporation from sweating is one. Others include breathing out warm air and radiation of heat through the skin. Heat illness occurs when these systems fail, or don’t perform adequately.

Precipitating factors

• Physical exertion.
• Hot and humid climatic conditions.
• Inadequate fluid intake.
• Infections.
• Working in poorly ventilated environments.
• Wearing heavy, dark coloured clothing on hot days.
• Taking some medications.
• Being con.ned to a small, poorly ventilated space.
• Wearing constrictive individual protective equipment.

The manual identifies four different levels of heat illness:

Heat syncope: A person faints in a hot environment and there is no other identifiable cause.

Heat cramps: Muscular cramps after physical exertion, while internal body temperature may be normal.

Heat exhaustion: Moderately elevated body temperature. Casualty is pale, sweating and thirsty.

Heatstroke: A very high body temperature, which leads to unconsciousness and death.

We’ll focus on heat exhaustion and heatstroke. The .rst step in the treatment process should always be the DRABC basic first aid principles.

Heat exhaustion

The most common form of heat illness, heat exhaustion is caused by fluid loss from sweating, usually through physical exertion without adequate fluid replacement. A reduction in body fluids means a reduction in blood volume, which ultimately means less blood gets to the vital organs, so the casualty suffers a mild form of shock.

Signs and symptoms

• Profuse sweating.
• Exhaustion and weakness.
• Dizziness, headache and faintness.
• Nausea and vomiting.
• Rapid breathing and shortness of breath.
• Weak, rapid pulse.
• Pale, clammy skin.
• Skin may be cool to touch.

Treatment

• Move casualty into the shade with circulating air.
• Lie casualty down.
• Loosen or remove unnecessary clothes.
• Sponge with water.
• Give fluids to drink.
• Apply cold packs to the groin and armpits.
• Seek medical assistance if casualty vomits or doesn’t recover promptly.

Heatstroke

Heatstroke is a potentially life-threatening condition – 50-70 per cent of people who suffer heatstroke and are not treated will die.

Heatstroke occurs when water levels in the body become so low that sweating stops and therefore the body’s natural cooling system fails completely. Vital organs, begin to overheat and fail.

Signs and symptoms

• Body temperature of 40 degrees or more.
• Hot, .ushed and dry skin, but the casualty may still be sweating.
• Agitation and mental confusion.
• Dizziness and visual disturbances.
• Initially a pounding rapid pulse, which gradually weakens.
• Altered mental state, which may progress to seizures and unconsciousness.

Treatment

• Move the casualty to a cool environment and remove almost all clothing.
• Apply cold packs to the neck, groin and armpits.
• If possible, cover the casualty with a wet sheet and fan to increase air circulation.
• If unconscious, place the casualty in the lateral position.
• If there is no pulse or breathing, start CPR and keep cooling.
• Seek urgent medical assistance.
• Evacuate the casualty as soon as possible.

The manuals

Documentation for the treatment of heat and cold illness can be found at http://adel2.defence.gov.au:8087/pdf/lwdc/lwpg/LWP-G_1-2-5/multi/Chapters/LWP-G_1-2-5_Basic_First_Aid_CHAP11.pdf

The Defence Safety Manual http://defweb.cbr.defence.gov.au/home/documents/data/DEFPUBS/DEPTMAN/SAFETYMANV2%5CV2P1/01.pdf provides information for supervisors and commanders on prevention of heat illness and management of training and activity in hot environments.

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