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Cold water immersion

4 stages of response to cold water immersion (from Giesbrecht)
1. Cold water shock
2. Cold incapacitation
3. Hypothermia
4. Circum rescue collapse

Cold water shock

Gasping followed by hyperventilation. Lasts up to a minute usually.
Without a PFD this may well be associated with inhalation of water and death; this is more likley in rough water.

Cold incapacitation

Cold will affect nerve and muscle function.
In around 10 minutes useful movements will become very difficult/impossible.


As core temperature decreases, mental and physical capabilities decline.
If you have a PFD hypothermia will usually take at least 30 minutes to develop.
The rate of heat loss can be slowed by adopted the HELP or by huddling. It will be slowed by protective clothing.

Circumrescue collapse

There are probably several factors that cause this, but rescuers can minimise the risk by rescuing casualties as horizontally as possible.

overview video from "cold water boot camp"

video on cold water shock
Cold Water Boot Camp USA, The First 60 Seconds Short from Brendan O'Donnell on Vimeo.

video on delaying hypothermia after cold water immersion
Cold Water Boot Camp USA, Surviving Cold Water Short from Brendan O'Donnell on Vimeo.

1 - 10 - 1 rule

You have one minute to start to breathe normally.
You have 10 minutes of useful movement (ie the window in which self rescue is possible)
You have 1 hour before unconsciousness from hypothermia (assuming you have flotation device)

Surviving cold water immersion
Cold water immersion
Presentation on cold water immersion by Mike Tipton

link to video by Gordon Biesbrecht on cold water immersion (takes a long time to download)



Drowning/near drowning (eMedicine)
European Resuscitation Council Guidelines on drowning
AHA guidelines on drowning
JRCALC guidance for immersion incidents

"The International Liaison Committee on Resuscitation (ILCOR) defines drowning as “a process resulting in primary respiratory impairment from submersion/immersion in a liquid medium. Implicit in this definition is that a liquid/air interface is present at the entrance of the victim's airway, preventing the victim from breathing air. The victim may live or die after this process, but whatever the outcome, he or she has been involved in a drowning incident”. Immersion means to be covered in water or other fluid. For drowning to occur, usually at least the face and airway must be immersed. Submersion implies that the entire body, including the airway, is under the water or other fluid. ILCOR recommends that the following terms, previously used, should no longer be used: dry and wet drowning, active and passive drowning, silent drowning, secondary drowning and drowned versus near-drowned."

Recommended books

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