Springtime is here, more time is now available to be out in the bush. Whether you go on a day-hike or on a hunting trip, air temperature is increasing. So be aware, heat can kill you, and is just as dangerous as cold.

The two major types of heat illnesses, heatstroke and heat exhaustion, occur when the body overheats. Let’s discuss both separately. Heat stroke is the most severe of the two.

Heat exhaustion
This occurs with prolonged exposure to hot humid climate, no fluid replacement and long period of fluid loss due to excessive sweating. Conditions can worsen if the patient vomits and has diarrhea.

Signs and symptoms
A general feeling of discomfort and unwellness, together with thirst, is the most important and common sign. Other signs are:

• Nausea and vomiting
• Anxiety
• Loss of appetite
• Fainting
• Cramps in muscles
• Headache
• Rapid pulse
• Poor muscle co-ordination
• Spots before eyes when quickly standing up or lying down

Treatment
The best possible treatment is to get out of the sun, away from the heat and into a cool environment. Also very important is rest. Then administer fluids orally or intravenously, to aid in sweat loss. Use a 1/4 teaspoon of salt to every 500ml of water.

Heat stroke
The most dangerous of the two is heat stroke. It can be fatal and needs to be treated as soon as possible. It can occur when a person is engaged in strenuous activity in a hot environment and is unable to dissipate the heat his body generates. In the body the core temperature is increased to 39 to 41°C. The heart, cellular function and the central nervous system are depressed. Death may occur if the core temperature is not lowered. The rise in body temperature will eventually produce kidney, liver and brain damage. The body’s metabolic rate increases by 13% with every 1°C increase.

Signs and symptoms
These are similar to heat exhaustion, but more serious and potentially fatal.

• Diarrhea.
• Hot and dry skin.
• Low consciousness.
• High pulse.
• Short of breath.
• Low blood pressure.
• Seizures.
• High temperature.
• Nausea and vomiting.
• Dilated pupils.

Treatment
Cool patient as soon as possible, cool with cold, wet shirt or sheet. Also, fan the patient with a magazine, hat or piece of cardboard. Temperature needs to drop to 38°C. Patient could go into shivering state. This needs to be controlled, since this will raise the body’s tempera-ture. Patient should be rushed to a medical facility as soon as possible. An unusual sign to look for is the lack of perspiration.

Precautions
To be cautious and prepared may save your life. Here are a few precaution pointers to help you:

• Rest period – Physical fitness can be an advantage to you, take rest stops every 30 minutes, you can progress to a 10 minute break every hour.
• Sunlight – Keep out of direct sunlight and try to stay in the shade as much as possible.
  
• Fluids – The intake of salts (isotonic or hypo tonic) is very important on hot and humid days, also the intake of enough fluids.
  
• Acclimatize – In a hot climate it is difficult to maintain normal physical capability and a person will quickly become exhausted.
  
• Dehydration – Because of excessive sweating, vomiting and diarrhea large quantities of water are lost. This will be discussed in more detail later.
  
• Humidity and high temperature – When humidity is higher than 60% and the temperature is extremely high, heatstroke can become a danger. This happens because the body cannot control its own temperature through sweating.
  

Clothing – Its best to wear loose-fitting clothes (light colored). Dark colors retain the heat as do synthetic materials.

Dehydration
This condition is brought about by a loss of body water. It is assessed in percentages.
At 5% dehydration:

• Headache starts.
  
• Dry mouth.
  
• Little urine dissipating.
  

At 10% dehydration:

• Skin elasticity decreases.
  
• Eyes sunk into sockets.
  

At 15% dehydration:

• High pulse rate.
  
• Shortness of breath.
  
• No urine.
  
• Big drop in blood pressure.
  

Remember to try to consume 1.5litre of fluids for every 2litre lost. Without water a person can last about 2.5 days at 48°C, provided you spend the whole time resting in the shade. In extreme survival conditions at a temperature of 48°C and with about 2litre of water, you might cover about 56km on foot and last for about 3 days.

Remember: Never watste water!

In the bush you need to always boil or treat drinking water found at any stagnant source.
Always be prepared, wear a hat and carry enough water with you whenever you are out in the bush