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Cold Water Immersion
The Shocking Reality

Jumping in sounded like a good idea?!Think you're a good swimmer? It doesn't matter, if you suddenly and unexpectedly end up in the frigid coastal and inland waters of the Pacific Northwest. Every year, dozens of swimmers and boaters drown in lakes, rivers and coastal waters in the Pacific Northwest. But it may surprise you that many victims don't die as a result of poor swimming skills or the effects of hypothermia, but from the immediate effects of cold water immersion, or cold water shock.

Unlike hypothermia, the effects of cold water immersion can lead to death in just a few minutes and in some cases, instantly.

Sudden entry into the water can cause cardiac arrest, even for people in good health. The shock of the cold water can also cause an involuntary gasp reflex that can cause victims to inhale water and drown. After just a few minutes, the ability to swim or tread water is impaired as the victim loses muscular coordination. All of this can occur in water as warm as 69 degrees.

"Sudden cold-water immersion is a phenomenon that is becoming more recognized as a cause of death as compared to hypothermia," said Dan Shipman, recreational boating safety specialist with the Coast Guard's Thirteenth District office in Seattle.

True hypothermia usually doesn't normally set in until at least 30 minutes after being in the water, depending on body size and type, insulation of clothing and other factors. Even then, victims can survive for hours before losing consciousness and drowning.

So what can be done to protect yourself from the effects of cold water shock? Wear a survival suit or life jacket. 

Survival suits, which keep cold water away from the body, minimize the loss of body heat and muscular coordination. That gives victims a better chance to climb back onto an overturned boat, swim to shore or signal for help. 

Life jackets are just as important. Because a life jacket keeps a person's head above the water, the potentially deadly effects of the gasp reflex that can lead to aspiration and drowning are minimized. A PFD also provides some protection from the cold water and makes the wearer more visible.

But life jackets and survival suits are virtually useless unless they are worn at the time someone becomes immersed in cold water. 

 Man Overboard -A Survival Story


"Amazingly, many people are not prepared for accidental immersion in cold water by already wearing a survival suit or life jacket. They think that, if worst comes to worst, I'll just put it on in the water. That's a difficult enough task in warm water and calm conditions. In cold water, it's nearly impossible," said Ted Rankine, former chair of the Canadian Safe Boating Council.

Experts say that there are other things you can do to increase your chances of survival if you do end up in the water. First, don't panic. Keep your head above the water and concentrate on breathing. If you can find a way to get out of the water, do it quickly. 

Four Stages of Cold Water Immersion
Stage 1 -Cold Water Shock
When someone falls into cold water their first unconscious response is to take a large breath of air, called the "involuntary gasp reflex."  If their face is in the water when that gasp occurs, then their chances of survival immediately diminish.
Stage 2 -Swim Failure
After one has been in cold water for 3-30 minutes, there's a continued inability to hold one's breath, loss of coordination in the arms and legs results in cramping and inability to grab onto anything.  Swimming becomes increasingly difficult, and painful.
Stage 3 -Hypothermia
It usually takes between 15-30 minutes to reach this stage.  The first signs are uncontrolled shivering and the person starts to become disoriented.  As the body pulls blood away from the extremeties toward the organs, the person usually cannot use their arms and legs for self-rescue.  When severe hypothermia sets in, will eventually become unconscious.  A person's normal body temperature is around 98.6 degrees F.  Most people cannot survive a core body temperature below 85 degrees F.
Stage 4 -Post-Rescue Collapse
The hypothermic boater is not out of the woods after rescue.  Blood pressure can drop to a dangerously low level, inhaled water can damage tissues in the lungs (dry drowning), and heart problems may develop as colder blood from the extremeties is released back from the core of the body.