Monday, November 22, 2010

How to Avoid Drowning in Cold Water

Our guest contributor from the USCG Auxiliary spells out the new facts about Hypothermia

By Vincent Pica
District Captain, Sector Long Island Sound/South, D1SR
United States Coast Guard Auxiliary

A cool water cruise could turn deadly. ©iStockphoto.com/TT
Traditions Die Hard at Sea
It isn’t easy convincing mariners that a life-time of tradition and practice is wrong. And not everything we know and practice on hypothermia IS wrong – but some has been. So, here are the facts:

The first phase of cold water immersion is called the cold shock response. Data now shows that roughly 20% die in the first two minutes. They take on water in that first uncontrolled gasp, panic and drown, plain and simple. Surviving this stage requires you to stay calm and get your breathing under control. If you don’t, your life is measured in minutes and you won’t need your other hand to count them.

A further consequence of this phenomenon is that you will rapidly lose your physical capacity to swim. Even the strongest swimmer can’t fight Mother Nature – your body will constrict blood flow to the outer extremities and keep as much warm blood as possible around the inner core. We had this right. I’ve described it as “being drunk without the booze.” Fine motor skills go, followed by gross motor skills, followed by, well, death by drowning. You can’t swim without arms and legs (read: extremities) working.

What we had completely wrong was this.
It is impossible to get hypothermic in cold water unless you are wearing flotation, because without flotation – you won’t live long enough to become hypothermic. (source: Mario Vittone, USCG)
This leads me to the next thing we had completely wrong – “that a 50 year old man would last 50 minutes in 50 degree water.” All the timings are wrong – if you had a life-jacket on. The good news is that we last longer, far longer, before losing consciousness and ultimately reaching the point of no return.

Table courtesy of Cold Water Boot Camp

Don’t Lose Them During Rescue!
One of the things we also got wrong was how to rescue them. Rescuers would be well served keeping the victim horizontal – not vertical, ever – while getting them into the boat! Often, two rescuers, one with each arm of the victim, would “bob” the stricken mariner up and down, “1-2-3 and HEAVE in”, using some the natural buoyancy of the human body to help the rescuers get the person out of the water, over the gunwales and into the boat. This can kill them. This is because of what is called post-rescue collapse. The rescue itself is stressful to a fragile heart – potentially leading to cardiac arrest. They keel over right in front of you, as you haul them over the gunwales and try to get them out of wet clothes (a struggle in itself) and into dry ones.

Editor's Note
Rescuers know a lot about the dangers of boating in cold water - that's why new laws like those in New York requiring boaters to wear life jackets in cold weather are important to follow, even if some believe they "take away our freedoms" as one commenter told us. Please take a look at the facts presented by experts like Vincent Pica and Mario Vittone, as well as the Cold Water Boot Camp video we shared last year.