Tips Sailing / Practical sheets
Advice of the French lifeboats service: Preventing and treating hypothermia at sea
Preventing and treating hypothermia at sea
PREVENTING HYPOTHERMIA:
Hypothermia is a situation in which the central temperature of the body no longer allows the vital organs to function properly. It is one of the main causes of death at sea.
Most body heat is lost by the following parts of the body:
-The head: when unprotected it can lose up to 50% of the heat produced by the body.
-The neck, the sides, the groin.
Protect these areas first, isolating them from contact with the sea, wind and any cold surface if possible...
In normal conditions the body gets rid of 95% of the heat it creates. There are two ways in which the body copes with a cold environment:
-Peripheral blood vessels contract to reduce blood flow to the surface and just under the skin, and gradually to part of or all of the limbs (goosebumps, cold feet and hands…)
-More intense ways of producing heat, from "vibrating" the muscles (shivering) to complete convulsions.
Learn to recognise the first signs of hypothermia in yourself and your crew members: shivering, confusion, clumsiness, unconsciousness.
Protect yourself from the cold:
-Do not drink alcohol.
-Eat properly, preferably warm food.
-Get enough sleep.
-Seasickness causes dehydration that induces hypothermia.
-Drink enough water.
-Wear a woollen hat that covers the back of the neck. If your feet are cold, cover your head.
-Wear woollen and/or synthetic clothing but avoid cotton (e.g.: jeans) that stay cold when wet.
-To protect yourself from the cold, wear several layers of clothing (loose-fitting) rather than a chunky sweater.
-Shield yourself from the cold and damp.
Minimise the effects of falling in the water:
-If you have a drysuit, practise getting it on in under one minute (even at night and in bad weather).
-Know where it is kept.
In the water:
-Put on your drysuit or your life vest, even in the water.
By yourself: curl up in a foetal position tucking in your arms and legs in order to diminish heat loss
In a group: cling close together to form a huddle. Put children and wounded at the centre.
These positions will prolong survival time by 50%
-Do not swim: swimming will end up killing you (cold + fatigue).
-Hold on to anything that is afloat, or fasten yourself to a float, if needed, and, if possible climb on top to get as much of your body out of the water as possible.
TREATING HYPOTHERMIA:
First aid:
Move a person with hypothermia very gently as any kind of shock may kill them (the heart is in an extremely fragile state).
Put the casualty in a heated place, or out of the wind if that is not possible. Put the casualty in a plastic bag, sleeping bag or roll them up in blankets. Their head and back of their neck must be covered.
The casualty is conscious:
-Do not give them any alcoholic drink as this may kill them.
-Do not rub them (you will send the cold blood from the limbs back towards the heart and risk killing the person)
-Take off their wet clothes, using scissors if necessary.
-Dry the casualty by gently tapping them with a towel or absorbent paper, etc. Above all, do not rub them down.
-Put warm water bottles around their head, neck and sides.
If the casualty can stand upright without difficulty, give them a warm sugary drink.
-Let the casualty warm up gradually for as long as ten hours if needed. Check their pulse, breathing, level of consciousness.
The casualty is unconscious:
-Place them on their side (recovery position)
-Take off their clothes by cutting them.
-Dry the casualty by gently dabbing their body. Do not rub them down.
-Let them warm up naturally in a heated place.
-Cover the casualty's head and back of the neck as well as their body with blankets.
-Do not massage or rub their body down in any way, as this may kill the casualty. Do not try to perform a heart massage without the advice of a specialist.
-Constantly monitor their progress as well as their pulse, breathing, consciousness. (the heart rate of a person with hypothermia may be very slow, one beat per minute)
Warning: a person with hypothermia may appear to be dead and be brought back to life.
