I came across these two articles on Drowning and Cold Water Shock & Recovery, they make interesting reading so I thought I would share these. Some very good points to remember.
Drowning – Doesn’t Look Like Drowning
<edit> same as post above</edit>
Cold Water Shock & Recovery
I’m going to come right out and tell you something that almost no one in the maritime industry understands. That includes mariners, executives, managers, insurers, dock workers, for certain – fisherman, and even many (most) rescue professionals:
It is impossible to die from hypothermia in cold water unless you are wearing flotation, because without flotation – you won’t live long enough to become hypothermic.
Despite the research, the experience, and all the data, I still hear “experts” – touting as wisdom – completely false information about cold water and what happens to people who get in it. With another season of really cold water approaching, I feel compelled to get these points across in a way that will change the way mariners behave out there on (or near) the water.
What follows is the truth about cold water and cold water immersion. I know that you think you know all there is to know about hypothermia already (and maybe you do), but read ahead and see if you aren’t surprised by something.
When the water is cold (say under 50 degrees F) there are significant physiological reactions that occur, in order, almost always.
You Can’t Breathe:
The first is phase of cold water immersion is called the cold shock response: It is a stage of increased heart rate and blood pressure, uncontrolled gasping, and sometimes uncontrolled movement. Lasting anywhere from 30 seconds to a couple of minutes depending on a number of factors, the cold shock response can be deadly all by itself. In fact, of all the people who die in cold water, it is estimated that 20% die in the first two minutes. They drown, they panic, they take on water in that first uncontrolled gasp, if they have heart problems – the cold shock may trigger a heart attack. Surviving this stage is about getting your breathing under control, realizing that the stage will pass, and staying calm.
You Can’t Swim:
One of the primary reasons given by recreational boaters when asked why they don’t wear a life jacket, is that they can swim. Listen up, Tarzan; I swam for a living for the better part of my adult life, and when the water is cold – none of us can swim for very long. The second stage of cold water immersion is called cold incapacitation. lacking adequate insulation your body will make its own. Long before your core temperature drops a degree, the veins in your extremities (those things you swim with) will constrict, you will lose your ability control your hands, and the muscles in your arms and legs will just flat out quit working well enough to keep you above water. Without some form of flotation, and in not more than 30 minutes, the best swimmer among us will drown – definitely – no way around it. Without ever experiencing a drop in core temperature (at all) over 50% of the people who die in cold water, die from drowning perpetuated by cold incapacitation.
You Last Longer than You Think:
If you have ever heard the phrase, “That water is so cold, you will die from hypothermia within ten minutes.” then you have been lied to about hypothermia. For that matter you can replace ten minutes with twenty, or thirty, or even an hour, and you’ve still been lied to. In most cases, in water of say 40 degrees (all variables to one side), it typically takes a full hour to approach unconsciousness from hypothermia, the third stage of cold water immersion. But remember, you must be wearing flotation to get this far.
We are all different in this regard, but I once spent an hour in 44 degree water wearing street clothes and my core temperature was only down by less than two degrees (I was not clinically hypothermic). It was uncomfortable to be sure, and I wouldn’t recommend finding your own limit, but it probably would have taken another hour to lose consciousness, and an hour after that to cool my core to the point of no return. The bodies efforts to keep the core warm – vasoconstriction and shivering – are surprisingly effective. The shivering and blood shunting to the core are so effective, that twenty minutes after jumping in (twice the “you’ll be dead in ten minutes” time), I had a fever of 100.2.
Rescue Professionals Think You Live Longer:
There is a good side to the misconceptions about hypothermia. Should you ever be in the water in need of rescue, you can be certain that the Coast Guard is going to give you the benefit of every possible doubt. When developing search criteria – search and rescue coordinators use something called the Cold Exposure Survival Model (CESM): It is a program wherein they enter all the available data about the victim (age, weight, estimated body fat, clothing, etc.) and about the environment (water temp, sea state, air temp, wind) and the software spits them out a number that represents the longest possible time you can survive under those conditions. I plugged my own information into it once and it said I could survive for over 4 hours in 38 degree water wearing nothing but a t-shirt and jeans and no flotation. I can tell you from experience that the CESM is full of it – I’d give me 35 minutes tops – but the error is comforting. If the program that determines how long I might live is going to be wrong – I want it to be wrong in that direction.
Out of the Water is Not Out of Trouble:
I lost count of the number of survivors I annoyed in the back of the helicopter because I wouldn’t let them move. I had a rule – if they came from a cold water environment – they laid down and stayed down until the doctors in the E.R. said they could stand. It didn’t matter to me how good they felt or how warm they thought they were. Because the final killer of cold water immersion is post-rescue collapse. Hypothermia does things besides making everything colder. Victims are physiologically different for awhile. One of the things that changes is called heart-rate variability. The hearts ability to speed up and slow down has been effected. Getting up and moving around requires your heart to pump more blood, being upright and out of the water is also taxing, then any number of other factors collide and the heart starts to flutter instead of pump – and down you go. Victims of immersion hypothermia are two things; lucky to be alive, and fragile. Until everything is warmed back up – out of the water and dry is good enough – mobility comes later.
Did You Learn Anything?:
If you did, then hopefully you’ll use it to make good decisions when it comes to being safe on and around cold water; good decisions like these:
1.When working on deck, wear flotation. This includes, especially, all fisherman in Alaska. I couldn’t find more recent research, but the 31 Alaskan “fell overboard” casualties in 2005 died from drowning, not cold water. Not one of them was wearing flotation. Many couldn’t stay above water long enough for their own boats to make a turn and pick them up…..over a life jacket.
2.If you witness a man overboard – getting the life ring directly to them is critical (vital – step one – must do it). Make certain that all-important piece of safety gear is not just on your vessel, but readily available and not tied to the cradle.
3.When working on deck – wear flotation. I said that already? Well, when I quit reading search reports that end with “experienced” mariners dying because they thought they understood cold water – I’ll come up with better advice.
For more advice about how to handle an accidental immersion into cold water – please watch Cold Water Boot Camp – it is one of the best 10 minutes on immersion hypothermia ever produced. For even more advice, ask me a question on the discussion boards.
Sitting in the chief’s office of Coast Guard Station Fairport Harbor in Mentor, Ohio, I’m reading the legal release that I have to sign if I want to be part of this project. I’m reminded again that one of the risks associated with cold water immersion is “sudden cardiac arrest.” A few paragraphs down I’m asked to release the project’s sponsor from any responsibility on behalf of myself and “my heirs” (excuse me?) should the rescue team be unable to revive me. I think, “Seriously, what the hell am I doing here?”
Beyond Boot Camp; Rescue, Recover, Rewarm – is a follow up DVD to Cold Water Boot Camp on the best techniques and practices used to safely recover hypothermic victims from cold water. My job? Easy. Get in the water and stay there until I am hypothermic. If you read my last article, then you know it will take at least an hour in the sub 40 degree lake to get my core temperature to drop that far. I sign the form and think one more time, “what the hell am I doing here?”
Two days later I’m lying on a stretcher, wrapped in a cocoon of blankets, violently shivering and in considerable pain. The water temp on lake Eerie had dropped to 32.6 – the effect freezing water has on your hands, feet, and other ….parts… is amazing. Dr. Gordon Geisbrecht – the project’s medical director and the world’s leading authority on environmental injury – had lowered the max immersion time (thanks Doc) to insure that the pain was not accompanied by real damage. Still, me and the other idiots who signed the release form were in considerable pain and discomfort. Looking up at the professional medics, firefighters, Coast Guard, and other municipal rescue workers ; I realized exactly what the hell I was doing there. We were all learning things.
Being recovered from Lake Eerie – December 2010
It turns out that there are as many misconceptions about the treatment of hypothermia as there are myths about the condition itself, and if this project would help save lives like Cold Water Boot Camp did before it, then that was reason enough to be cold and wet just one more time.
The National Water Safety Congress released the DVD last winter, but I thought I’d share to gCaptain readers what we learned about caring for victims of accidental cold water immersion.
Important Note: What follows is advice about caring for victims pulled from cold water – specifically tailored for mariners at sea. This is because “at sea” is a place that often also means “hours, if not days, from a advanced care”. That makes “at sea” a much different place than say “at the marina – or beach” where professional medical assistance is nearby. As working mariners – the average gCaptain reader may need to handle victims from the water to full recovery – so this advice is for you.
Be careful getting them out: Approximately 20% of those that die from accidental cold water immersion – do so during the rescue phase. There are ways to get victims out of the water right and ways to do it very wrong. That’s because depending on a number of variables including time in the water, age, health, and half a dozen others – victims of cold water immersion may be in a very fragile physiological state.
Just being in water does things to the human body that change it. The pressure of the water on the limbs – particularly the legs (because they are deeper) – forces blood out of the legs and into the core and this raises blood pressure. When the water is cold, we get the added effect of constricting blood vessels in the outer skin layers and extremities (vasocontriction – see The Truth About Cold Water) and this also raises core blood pressure. The body is trying to keep the core warm and more blood in the core and less every where else helps.
Without digging in too deep – you should know that when a person spends long periods of time in cold water, they have changed physically. Their bodies contain warm blood and very cold blood; their heart has a decreased ability to speed up when it needs to, and veins and nervous systems have been temporarily altered in such a way that may have them on an edge very close to significant heart malfunction. They are fragile – and must be treated carefully: Here are some best practices for the recovery from the water phase:
•Recover them as horizontally as possible: If you can avoid lifting them out of the water vertically, do it. If you must lift them out vertically, get them laying down immediately once on board. The hydrostatic pressure on their body has made it easier for their bodies to maintain blood pressure – as soon as they are removed, the heart has to work harder – and a cold heart doesn’t do well at working harder.
•No walking: They shouldn’t be walking around until the are completely recovered. There is some very cold water in those limbs and for the time being, you want it to stay there.
•Don’t make them work for it: Don’t ask them to “pull” or to exert themselves in their own rescue if it can be avoided. Remember, they are in a fragile cardiovascular state and climbing that net after being in the freezing water may be the last thing they ever do.
•Remember – None of this is as important as getting them out: If you’re at sea, and the only way to get them aboard is by hauling them over the rail like so many pounds of tuna – then haul away. Just do it….carefully, and be very gentle with them once they’re aboard.
•Stay calm – move slow: They do have to get out of the water – but doing things slow will make them smooth and smooth is what you want. If recovered to your rescue boat, do not rush at full speed back to the ship. Pounding through waves is just as bad for them as any other rough handling.
Get Them Dry:
Just because you got them inside and out of the elements, doesn’t mean that they aren’t still cooling off. Wet clothes will continue to cool them off and hinder their recovery. Getting them dry sounds easy enough, but this is another area where there is a right way and a wrong way to do things:
•All modesty and dignity can be reserved for another day – once you have them inside the cabin – absolutely every stitch of wet clothing comes off. It is also better to cut clothing off (safely – medical bandage scissors are best) rather than have them endure the flexing and stretching of the limbs that occurs by pulling it off the regular way. You want them laying down and moving as little as possible.
•Use towels to gently pat the water from their skin and hair – NEVER rub them dry. Trying to rewarm a victim by vigorous rubbing of their skin actually has the opposite effect. It makes them colder. A victims skin contains the coldest blood in their bodies and by rubbing it, you essentially push it back into play before the body is ready for it.
•Thickness equals warms: wrapping them in layers of loose fitting blankets and keeping them inside a warm, dry place is the first goal after removal from the water. Everything you have done so far has been about preventing further heat loss: If they are out of the elements, dry, and covered up – you have done at least that.
To get an idea how being wet in a cold environment can effect the human body, watch this video shot during the first day of “Beyond Boot Camp”. This section was filmed to show rescuers how to remove a victim from the water and to a waiting ambulance. I was only in the water for a minute – but after exposure to the 24 degree air and blowing wind for just a few moments – my wet clothes really did a number on my ….comfort…the intense shivering is not an act.
Keep Them Down
Now that they are dry and out of the elements – the recovery can begin. If they are intensely shivering, that’s good. But for those who have never seen it before, it is a little disconcerting. It looks awful and feels even worse, but it is just the body trying to regulate temperature. What I can tell you from experience is that the first ten minutes out of the water is far more painful than any ten minutes in it – but that if they are down and dry and shivering – things are looking very good. What you want to do next is help them….wait for it…keep shivering
Get Them Calories:
If your recovered victim has been in the water long enough to be shivering violently, then they have been burning an awful lot of calories. Depending on when they last ate, they may be running low on available fuel and need a boost. Knowing that, what do you think is better for your freezing – shivering – crew member; a warm cup of water, or an icy cold soda? (pick the soda) A warm sugary cocoa is better, but the point is that calories are more important than the temperature of the drink. They need the calories to fuel the shivering until they are fully recovered.
Warm Them Up (maybe):
There are many methods and devices for adding heat to help rewarm hypothermic victims. They range from complex medical devices like warm air infused blankets to simple heat packs or hot water bottles. But if it was my ships hospital, I’d just make sure I had a simple heating blanket. Put on low to medium they will provide radiating heat and everyone knows how to use them. Forced air systems have lots of parts to go bad, and heat packs can cause problems – even blistering – if they stay in contact with very cold skin. Simply cranking the heat up in the cabin is another way to assist in recovery. A warm bath or shower may seem like a good idea, but it isn’t. Remember, the blood in their skin will be cold and not moving for a while. What feels warm to you may be scolding hot to them.
One of my favorite myths about treatment is the old “climb in the sleeping bag with them” idea. Don’t – do not – back off. That may be a good idea to stay warm but not a good idea to re-warm a victim of cold immersion. They do not need anyone pressing up against their cold skin and agitating their cold muscles.
People recovering from cold water immersion can look miserable. Their skin may be a red like a bad sunburn, they can shake violently, and they just sound like they are in pain – and they are. But here is the thing: If you have done everything above and they are red and shivering and complaining about how miserable they are – they are probably just fine. They are as uncomfortable as they have ever been in their lives, sure, but they are fine. All you can do is let them lay there and get over it. Just watch them until they are absolutely bored from laying there. None of this “get back to work” stuff until hours have passed. Of course, contact your medical authority and pass all pertinent information for recommendations. Did they injest or inhale sea water? If they did, it can cause problems unrelated to the cold that may require a medevac just the same.