Extremes in environmental conditions can be serious and life threatening.

Enviromental Conditions

1. Hypothermia

Hypothermia results from excessive cooling of the body core. Generally, hypothermia occurs in cold conditions where clothing may not provide adequate insulation, and is often worsened by physical and mental exhaustion. Onset of hypothermia is more rapid if the body is immersed in water.

The body core
The body core

Normally, in cold conditions, the body core maintains heat by decreasing blood supply to the legs and arms. This has the effect of lowering muscle activity which results in the characteristic signs of clumsiness and lack of coordination associated with hypothermia. If the body continues to be cooled, these signs will worsen; the person will become drowsy, erratic and sometimes irritable. This can lead to unconsciousness and death if no action is taken.

It is important to remember that hypothermia can affect any person. Often hypothermia is only thought of in the context of outdoor activities, but other groups of people can also experience this condition – e.g. elderly people after a fall in a cold house or garden.

Symptoms and signs – Not all may be present

  • patient feels cold to touch and may be shivering violently
  • cold environment
  • tiredness – patient may fall behind the others outdoors
  • clumsy, uncoordinated, may fall over and appear drunk
  • changes in mood with irritability, irrational behaviour
  • patient may resist help
  • slow to respond to questions
  • shivering may decrease and stop – this is a critical sign
  • loss of consciousness
  • pale or blueish skin colour

How you can help

The best treatment for hypothermia is prevention. People who go tramping or engage in other outdoor activities should ensure they are wearing adequate clothing for insulation. Frequent stops for drinks and snacks are important.

If you suspect hypothermia the aim of managing the patient is to stop further heat loss and warm the patient slowly.

  • Provide immediate shelter out of the wind and dry clothing.
  • If fully conscious, give warm drinks, sweets, chocolate, etc.
  • Use body contact to reduce heat loss and slowly warm patient – e.g. huddle around the patient in a sleeping bag.

If hypothermia is mild, and rest, warmth, drinks, etc. allow recovery, the patient can continue tramping at a comfortable pace provided weather conditions are good.

If hypothermia has reached the stage where the patient is becoming drowsy, urgent medical assistance is required. The patient may need CPR if they become unconscious with no signs of life.

Call 111 for an ambulance.


2. Heat-related conditions

Overheating can cause a range of conditions. Because it is not easy for a first aider to determine the exact condition an overheated patient is suffering from, management of such patients is described here in a general way.

Heat-related conditions can be caused by overexertion, particularly in warm to hot environments, from prolonged physical exercise, and dehydration.

Symptoms and signs – Not all may be present

  • Weakness
  • Thirst
  • Sweating
  • feeling hot
  • nausea and vomiting
  • rapid breathing
  • confusion
  • flushed skin, which may become pale

The following signs and symptoms indicate a serious heat-related condition requiring urgent medical assistance and rapid cooling:

  • no sweating
  • confusion
  • seizures
  • unconsciousness

How you can help

1.    Rest in a cool place
2.    Give the patient fluid to drink

  • Most patients will respond well with water, fruit juice, or their soft drink of choice.

If unconscious, call 111 for an ambulance and DO NOT give the patient anything to drink.

3.    Arrange medical attention

Or call for an ambulance, if the patient’s condition gets worse or if they are unable to drink fluids.

4.    Rapid cooling

  • For serious conditions this can be achieved by removing heavy clothing, spraying or sponging with cool water, and applying cold packs to the armpits, groin and neck. A fan directed onto the patient is also helpful.

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