Why hot chocolate is good if you've fallen into cold water

Of all the things I have ever read about the importance of life jackets when it comes to water safety or survival, the “immediate gasp response” has to be the most effective.

Ian Gilson, on the board of directors for the Canadian Safe Boating Council, said there are a number of things that happen to the human body once it lands in water 15 C and below. One of the first: Your blood vessels constrict.

“Your heart has to pump harder to provide that same volume of blood throughout your body, which is why some people have a heart attack at that particular point,” he said.

The immediate gasp response (shudder) also happens almost immediately after you take the plunge. Basically the shock and submersion causes you to breathe in forcefully, said Gilson.

“If you are not wearing a (personal flotation device) and your head is below the water, you can take more than a litre of water into your lungs, which no amount of coughing or sputtering is going to allow you to expel," he said.

If you make it through the plunge without a heart attack or sucking in vast quantities of water, you have about 10 minutes before your muscle strength wanes. “After about 10 minutes, you lose the capability of meaningful movement in cold water,” said Gilson.

Gilson notes on top of wearing a life-jacket or personal floatation device (that is the most important thing) anyone setting out on the water for any length of time needs to tell a responsible person on shore where they are headed, who they are with and when they should be coming back.

“This, combined with a detailed boat description constitutes a float or sail plan. Search and Rescue resources can then be dispatched if you’re late arriving home,” said Gilson. “These steps can save your life.”

Boaters should also take preventive steps by dressing warmly and having some sort of insulated suit on board to protect them if they fall in, he said.

“Being on the water is a wonderful activity. You just have to realize that one minute you can be having the time of your life... and the next you can be fighting for it. Cold water presents just those types of dangers!”

So what if your friend is the one who got dunked (hopefully in a life jacket) and you manage to get them out and medical attention is not immediately available?

“Try to take them out as horizontally as possible so the blood doesn’t rush to their feet and they have a drop in blood pressure that can cause ventricular fibrillation,” or wildly uncoordinated beating of the heart, said Gilson.

You also want to warm them slowly and get them out of wet clothing.

“You can cut (clothing) off; don’t try to wrestle them off and move their arms around.”

You only put people in the shower who you consider to be mildly hypothermic, to avoid, among other things, hurting their skin, notes Gilson.

The best drink to give someone who has been immersed in cold water would be hot chocolate, because it is warm and the chocolate provides sugar, which provides the energy, he said.

Warming people up sailor style – with a bolt of hard booze – is definitely not a good idea. Alcohol thins the blood, said Gilson.

We're assuming that means a stiff drink before you suit up and get tossed in the lake is totally out of the question – but who really wants to be less coordinated in that situation? We're also guessing a celebratory pint of beer several hours after immersion would get the green light.

Comments

[Chris Berneche]

The reason the casualty is removed horizontally is to gradually allieviate the pressure that the water is exerting on the immersed portion. If this is removed too quickly the cold blood will rush to the core and further reduce the body temperature.
Alcohol is a bad idea because it is a vasodilator and further increases heat loss.