Cold water survival

[florriej]

Here is some info from the book "The Basic Essentials of Hypothermia", by William Forgey, MD, (1991) a small book packed with tons of good info on treatment & prevention of hypothermia, nutrition requirements in the cold, and physical responses to cold.

"Exercise in cold water can increase cooling rates by 35 to 50 percent. Some authorities have felt this was due to increased blood flow in muscle [encouraging cooled blood from extremities to travel into core], while others feel it is the increased turbulence of the water which increases the rate of cooling [not allowing body to heat water around it]. "Regardless of which, movement such as swimming in water decreases the survival time. Depending upon circumstances, perhaps swimming to a nearby point of rescue is the best option. But for those who must remain in the water until rescue arrives, remaining as still as possible is the best choice" [assuming you can't climb on top of a boat and out of the water].

"Cold stress acclimatization and food intake have little effect on the rapid heat loss experienced during immersion in cold water."

He goes on to talk about the elsewhere discussed Huddle position of curling up with your life jacket. However, it is apparently difficult to maintain this position without getting washed around by the water and repeatedly getting head and neck wet, which negates any positive affect. If that happens, the author suggests straightening your legs, crossing legs at the ankles and bringing the thighs together, minimizing heat loss while not allowing you to go awash in the water.

Chart of estimated survival times in hours of lean subjects (11% body fat) wearing various types of clothing in rough seas at 43 degrees F. (taken from Wilderness Medicine Newsletter, April 1990)

//// time to incapacity// time to unconsciousness // time to cardiac arrest

light weight clothing: .4 - 1.3 hours// .8 - 2.6 hours // 1.3 - 4.3 hours

3.2 mm loose wetsuit: 1 - 2.9 hours // 1.9 - 6.0 hours // 3.0 - 9.9 hours

drysuit w/fiber-fill insul: 2.9 - 8.8 hours // 5.7 - 18.2 hours// 9.1 - 30 hours

"It will be noted that there are significant variations in lengths of time until loss of coordination and probably death by drowning will occur." He doesn't go on to explain the variations, however, only stating that temp of water and amount of fat a person has affect rate of cooling, with cooling occuring faster for thinner people.

Just some stuff to ponder while sitting on the couch in front of a warm fire....

[JohnHuth]

That all sounds about right, based on my experience and the information I've read.

Also, the 50/50/50 rule doesn't make sense (note that your survival figures are for 43 degrees F, and there's a substantial change dropping from 50 degrees to 43).

[Phil Allen]

Just thinking: maybe the 50/50/50 "rule" takes into account not only hypothermia induced mortality, but that of cold shock and cold induced aspiration of sea water. Or maybe it's an old wives tale used by the CG and others to scare us into doing what's good for us.

Phil

[Gcosloy]

From the above it would seem that an investment in a dry-suit for 43 degree F. water is a no brainer. The dry-suit provides about three times the immersion time the wet-suit does before the respective ill effects set in. It would be helpful to see the same chart for warmer temperatures too. As an example I'm usually in a wet-suit in 50's water. Maybe I'm better of in a dry suit then as well.

[John Martinsen]

Dr. Popsicle, a scientist, on hypothermia...

http://www.nols.edu/alumni/leader/05spring...fmedicine.shtml

"It’s another hour until our body temperature drops far enough to make us critically hypothermic. The scientist’s simple message is “1 minute, 10 minutes, 1 hour.†We need to control our breathing and survive the first minute. Then we have 10 minutes to move carefully and thoughtfully, and an hour before we become gravely hypothermic. Knowing this, while we still need to promptly treat hypothermia, we don’t need to panic."

[Phil Allen]

Dr. Popsicle, a scientist, on hypothermia...

http://www.nols.edu/alumni/leader/05spring...fmedicine.shtml

"It’s another hour until our body temperature drops far enough to make us critically hypothermic. The scientist’s simple message is “1 minute, 10 minutes, 1 hour.†We need to control our breathing and survive the first minute. Then we have 10 minutes to move carefully and thoughtfully, and an hour before we become gravely hypothermic. Knowing this, while we still need to promptly treat hypothermia, we don’t need to panic."

Nice link and good info. I'd speculate that while we won't lose more heat through our neck and head compared to the rest of the body, it's probably the part of the body where the blood flow won't get shut down to prevent heat loss. Which explains why they always told us to put a hat on if we complained about cold feet.

Phil

[rylevine]

Nice link and good info. I'd speculate that while we won't lose more heat through our neck and head compared to the rest of the body, it's probably the part of the body where the blood flow won't get shut down to prevent heat loss. Which explains why they always told us to put a hat on if we complained about cold feet.

Phil

Interesting topic. Another factor is the loss of hand dexterity. I think that can happen faster than 10 minutes, and if it is needed for rescue (to work paddle floats, pumps, for balance and etc) it could be a problem independent of overall hypothermia. Gloves obviously help, but they are not waterproof and I've noticed my hands can get cold even with the gloves on while paddling (hence the pogues).

Bob

[tyson]

Interesting topic. Another factor is the loss of hand dexterity. I think that can happen faster than 10 minutes, and if it is needed for rescue (to work paddle floats, pumps, for balance and etc) it could be a problem independent of overall hypothermia. Gloves obviously help, but they are not waterproof and I've noticed my hands can get cold even with the gloves on while paddling (hence the pogues).

Bob

I keep wondering about a dry suit with built in gloves, much like the "socks". Two less seals to leak or fight with. I would wear a liner glove underneath and a more substantial neoprene glove over it. Then I could have DRY HANDS! :-)

Ty

[rylevine]

I keep wondering about a dry suit with built in gloves, much like the "socks". Two less seals to leak or fight with. I would wear a liner glove underneath and a more substantial neoprene glove over it. Then I could have DRY HANDS! :-)

Ty

Tyson,

It's a great idea. I can't believe this has not been tried.

Bob

[EEL]

It's a great idea. I can't believe this has not been tried.

I have seen diving drysuits with gloves at a diving shop and was told by the owner that they could add them to a paddling drysuit. The ones I saw had a locking metal ring attachment system and did not seem particularly suitable for paddling.

May not be done since for long journeys folks tend to use the drysuit on and off water where fine dexterity is needed for camp tasks etc. and you would not want integrity compromised by wear in hand area. Still, an interesting idea. Certainly warm hands after a lunch break in winter is a very good thing.

[rick stoehrer]

Tyson,

It's a great idea. I can't believe this has not been tried.

Bob

it is an idea that has been tried but not through a manufacturer.....i think bryan n used nordic blue gloves to do essentially what you're talking about...

myself, i'm a pogie guy even in the dead of winter...my hands can still get wet so long as they aren't exposed to the wind and i'm fine with no real loss of dexterity....it's when the wind hits em and they're wet that i have a problem.

[brambor]

I have briefly experimented with thin glove liners and surgical gloves under my neoprene gloves. It sure keeps the water out better than not wearing them and provides vapor barrier to keep the heat in.

I have seen diving drysuits with gloves at a diving shop and was told by the owner that they could add them to a paddling drysuit. The ones I saw had a locking metal ring attachment system and did not seem particularly suitable for paddling.

May not be done since for long journeys folks tend to use the drysuit on and off water where fine dexterity is needed for camp tasks etc. and you would not want integrity compromised by wear in hand area. Still, an interesting idea. Certainly warm hands after a lunch break in winter is a very good thing.

[glil]

May not be done since for long journeys folks tend to use the drysuit on and off water where fine dexterity is needed for camp tasks etc. and you would not want integrity compromised by wear in hand area. Still, an interesting idea. Certainly warm hands after a lunch break in winter is a very good thing.

A zipper across the back of the hands could allow free hands when needed. Keeping the wrist gasket would prevent water from getting into the rest of the drysuit. Having a way to roll the mittens up and out of the way when not needed might also be possible. Imagine DRY HANDS as well as cozy feet!

[rcohn]

From the above it would seem that an investment in a dry-suit for 43 degree F. water is a no brainer. The dry-suit provides about three times the immersion time the wet-suit does before the respective ill effects set in. It would be helpful to see the same chart for warmer temperatures too. As an example I'm usually in a wet-suit in 50's water. Maybe I'm better of in a dry suit then as well.

That was a drysuit w/fiber-fill insul: which I assume is diving level insulation. With the level of insulation kayakers use you won't last nearly as long.

Ralph

[rcohn]

I have seen diving drysuits with gloves at a diving shop and was told by the owner that they could add them to a paddling drysuit. The ones I saw had a locking metal ring attachment system and did not seem particularly suitable for paddling.

lots of options for attached gloves, DUI zip seals and gloves are a nice system that lets you choose seal or gloves and quickly replace torn seals.

Much greater advantage to attached gloves in diving compared to kayaking. I don't think they would be worth the hassle for kayaking, nordic blues are fine.

Ralph

[Paul Sylvester]

Forget attached gloves on drysuits for kayaking, too many problems..

Pogies or mittens for me

One option some may like.... NE Fishing gear in Portsmouth sells a neoprene glove that has a sleeve/ cuff that comes up your forearm. I have a worn out pair that I liked. You don't get that little bit of water hitting your wrist in waves.

Mine are labeled as "Mad Dog gear by Stearns"

[Brian Nystrom]

Forget attached gloves on drysuits for kayaking, too many problems..

That was the conclusion I came to as well. There are two major problems with the idea of attached gloves:

1- There are times on the water when you need the dexterity of bare hands, it's not just something you need on land. In a pinch, you need to be able to take off your gloves quickly, which leads to the next problem:

2- The quick detach systems designed for diving dry suits (wrist rings) totally compromise your dry suit when the gloves are detached. A capsize would result in t flood of water entering at the wrists. The wrist ring system is meant for use in an activity - diving - where you never take off your gloves except when donning or removing your gear before and after dives.

Dry gloves are great for keeping your hands warm, but they're a pain to get on and off. What I usually do in winter is to wear my dry gloves, but keep a pair of neoprene gloves on my deck as well. If I need to pull off the dry gloves and circumstances don't allow me to put them back on, I'll either stow them in my PFD or in the cockpit, then slip on the neoprene gloves and use them until I get to a place where I can put the dry gloves back on.

One option some may like.... NE Fishing gear in Portsmouth sells a neoprene glove that has a sleeve/ cuff that comes up your forearm. I have a worn out pair that I liked. You don't get that little bit of water hitting your wrist in waves. Mine are labeled as "Mad Dog gear by Stearns"

I have a pair of those too, and I agree that they're handy, though not as warm as dry gloves. I think I bought mine at Walmart in the hunting department (waterfowl hunters use them for setting decoys). Like all 3mm neoprene gloves, they develop leaks within a season of use. I now use mine mostly for washing the car in cool/cold weather. I can reach into a bucket of cold, soapy water without freezing my hands.

[florriej]

I'd speculate that while we won't lose more heat through our neck and head compared to the rest of the body, it's probably the part of the body where the blood flow won't get shut down to prevent heat loss. Which explains why they always told us to put a hat on if we complained about cold feet.

Hypothermia begins with the body keeping blood in the core to protect (warm) the essential organs, sacrificing the extremities. The brain is not protected in this, which is why symptoms of hypothermia include disorientation and poor judgement.

This blood thickening and remaining in the core happens over time when the body is too cold for too long, even if the person is doing all the right things - remaining hydrated and well fed. Remember the Monadnock Guide who died several years ago during that really cold winter? He was backpacking and night temperatures were minus 40 over 3 nights. He was experienced, had all the right equipment and knowledge but human bodies just can't manage certain conditions! His gear was found strewn all over the trail. I guess we gotta be smart enough to remember how fallable we are!

[rcohn]

2- The quick detach systems designed for diving dry suits (wrist rings) totally compromise your dry suit when the gloves are detached. A capsize would result in t flood of water entering at the wrists. The wrist ring system is meant for use in an activity - diving - where you never take off your gloves except when donning or removing your gear before and after dives.

There are diving systems using rings and wrist seals so that a torn glove will not compromise the suit. The main problem for kayaking is that you need help to fasten the rings, nearly impossible to make a secure seal using one hand.

Ralph

[bob budd]

When wearing dry gloves, its also important to carry at least two sets of liners. They can get damp/wet from sweat and the dry liners can be used while on a break. There are also mitten/gloves that are great for breaks and before/after the paddle.

[Phil Allen]

Hypothermia begins with the body keeping blood in the core to protect (warm) the essential organs, sacrificing the extremities. The brain is not protected in this, which is why symptoms of hypothermia include disorientation and poor judgement.

This blood thickening and remaining in the core happens over time when the body is too cold for too long, even if the person is doing all the right things - remaining hydrated and well fed. Remember the Monadnock Guide who died several years ago during that really cold winter? He was backpacking and night temperatures were minus 40 over 3 nights. He was experienced, had all the right equipment and knowledge but human bodies just can't manage certain conditions! His gear was found strewn all over the trail. I guess we gotta be smart enough to remember how fallable we are!

I don't know that specific case, but there are plenty of reports where the hypothermic person became delusional and believed they were too warm.

Phil

[Michael_Crouse]

This sometimes happen during the final stages. Your body starts shutting down everything unneeded for survival and the portion of the brian that regulates/understands temperature shuts down. I guess this makes since because at that point your brain knows you're freezing to death and doesn't need to know the exact temperature. This is of course a theory but it seems plausible.

People also become combative during the final stages. It's lots of fun fighting with a freezing person who refuses to put on a hat and jacket.

[Suz]

This sometimes happen during the final stages. Your body starts shutting down everything unneeded for survival and the portion of the brian that regulates/understands temperature shuts down. I guess this makes since because at that point your brain knows you're freezing to death and doesn't need to know the exact temperature. This is of course a theory but it seems plausible.

People also become combative during the final stages. It's lots of fun fighting with a freezing person who refuses to put on a hat and jacket.

The name for this is paradoxical undressing and according to the research happens quite a bit in later stages of hypothermia.

Suz

[nancysan]

The name for this is paradoxical undressing and according to the research happens quite a bit in later stages of hypothermia.

Suz

sounds rather unpleasant

[florriej]

The name for this is paradoxical undressing and according to the research happens quite a bit in later stages of hypothermia.

Suz

I may be mixing my concepts up here, but I seem to remember a phenomenon called somthing like "hunter's flush", where, in a last ditch effort towards survival, the body lets go of the blood in the core, releasing it to the rest of the body. This results in a feeling of heat, briefly, and thus the clothing removal. -Florrie