Image

Hypothermia - What to do

For people not used to cold water (temperature under 15 °C), sudden immersion is associated with two problems, either of which may result in death from drowning.

On initial immersion, the shock of the cold water coming in contact with the skin ("Cold Shock") can result in incapacitation and drowning in the first 2-3 minutes. For those who survive this and are unable to get out of the water quickly, progressive body cooling leading to hypothermia will follow in time. The rate of onset will depend on water temperature and the protective measures you have taken to reduce body cooling.

Here is some advice on how to prevent these conditions in the first instance and what to do if you do find yourself a victim of either.

COLD SHOCK

The term used to describe the initial response of a victim, unused to cold water after sudden immersion.

Signs and Symptoms:
Initial deep gasping
Uncontrollable rapid breathing, with possible dizziness and pins and needles
Panic
A large increase in both heart rate and blood pressure

Dangers:
Inhalation of Shock
Drowning
Stroke or heart attack

Prevention:
Use recognized 'man overboard' prevention equipment
Wear approved lifejackets
Wear clothing with good insulating and waterproofing properties
Wear Immersion Suits (dry/wet)
Hold on to some support and do not attempt to swim until symptoms have subsided (approx.2-3 min)
Exit the water as soon as possible

Follow up:
Monitor airway, breathing and circulation
Prevent further loss of heat
Protect from wind
Get medical help

HYPOTHERMIA
Following immersion, first, the skin and limbs cool rapidly; then the heart, brain, and other deeper parts of the body cool. Hypothermia occurs when deep body temperature drops by at least 2°C. Body build, body fat, fitness level and types of clothing worn, all affect its rate of onset.

Signs and Symptoms:
Early dulling of sensation in hands and impaired muscle function
Violent shivering with blueness around the lips
Armpits very cold
Muscles stiffness
Lethargy and disorientation
Slow and laboured breathing
Pulse weakens but difficult to feel in any case because of cold

Dangers:
Impaired sensation & muscle coordination may impair some early vital lifesaving actions involving hands
Loss of consciousness
Drowning
Cardiac arrest
Death

Note: Do not assume a person is dead; they may only be in hibernation.

Prevention:
Wear approved lifejackets
Wear Immersion Suits over warm clothing
Learn cold-water survival techniques (stay still with arms by sides and legs together - "HELP" position)
Get out of water as soon as possible (life raft; upturned hull, or any other refuge in air)

Follow up:
Prevent further heat loss (enclose in plastic bag)
Monitor airway, breathing and circulation
Move victim to shelter and lie flat
Insulate body and specially the head
Remove wet clothing if dry replacements are available.
If not:
Enclose body - except face - in large polythene bag or other waterproof material
Give warm sweet drinks if conscious, DO NOT give alcohol
Avoid rubbing the victims body

FACTS
a) It takes only 15 to 20 minutes in cold water before the temperature of the heart, brain and internal organs begin to drop but skin and muscle temperatures cool far quicker, which may impair some essential early lifesaving actions.
b) Children cool much faster than adults because they are smaller and have less fat. Boys usually cool faster than girls.
c) Swimming may give a feeling of warmth but it accelerates muscle cooling. The body may produce more heat when swimming but it is also more quickly lost from the arm and leg muscles. Once these muscles cool, swimming becomes more difficult or impossible.
d) Normal clothes will not produce much insulation against cold water, but they will slow down the rate of loss of vital body heat.
e) Wearing approved Lifeguards, Immersion Suits and properly fitting Wet suits will decrease the likelihood of hypothermia for all water sports enthusiasts.

CONVERSATION OF HEAT IN WATER

Retention of heat in water:
1) Avoid swimming if possible; floating or treading water increase the chances of survival. Remain still by using trapped air in clothes as a buoyancy aid. Better still wear a lifejacket.
2) Clothes will slow down the rate of loss of vital body heat.
3) H.E.L.P (Heat, Escape, Lessening, Position) - This position (legs together elbows to sides), may be adopted if wearing loss in calm water.
4) Immersion Suits: Wet suits provide extra buoyancy and reduce heat loss for considerable time, but dry suits are better for long-term survival.
5) Use of floating objects (e.g. Swamped or capsized boats) to get as much of the body as possible out of the water, even if the air feels colder you will always cool faster in water.

  • Irish Water Safety,  The Long Walk,  Galway,  Ireland.
  • © 2017 Irish Water Safety
  • Web Design By Webtrade.ie