Monday, November 20, 2006

Hypothermia by Bush Creatures, Guest Article


HYPOTHERMIA Guest Article by Bush Creatures

Bush Dad is the senior member of the Bush Creatures caching team. He is a long-time employee of a provincial fish and wildlife agency in Canada, worked as provincial boating officer, enforced boating safety regulations and has received training in cold water survival, ice travel and rescue and wilderness survival. He has, unfortunately, participated in body recoveries after boating accidents and has been involved in some major wrecks of his own before smartening up. The junior member of the Bush Creatures (thirteen year old Bush Girl) thinks her dad is a nag on wilderness safety and hypothermia but has learned that her dad doesn’t mess around, particularly when it comes to traveling with precious cargo.

October 30 on a northern lake. There had been a skim of ice on the water when we put the boat in to travel about a kilometer to our favorite duck hunting island. Our island was well sheltered from the rising wind by a larger island and it was a good day. By 5:00 p.m., we were chilled and tired and hungry and it was time to head back to the camp. Boat was heavy as we also had the decoys and blinds that we had taken out the evening before. Lake was choppy with a lot of spray. We passed the big island and turned into the wind for the 500 m ride back to the camp.
Three large waves later and we were swimming beside a swamped boat and grabbing for the life jackets we should have been wearing. It was fine, nobody panicked, the boat had enough floatation to hang on to in spite of our heavy clothes until we grabbed for the life-jackets floating beside us and got them on. Nobody drowned so this would be another story to laugh about. Unfortunately, the story goes on. Half an hour later as we were blown to the far shore, I was completely incapable of a rational thought, violent shivering had me unable to handle the minimal survival gear we had with us and it would have felt great just to close my eyes, let go of the swamped boat and die. I had just met up with hypothermia.

Hypothermia is generally defined as a lowering of body temperature below 35C or 95F. By the time the body core cools to below about 32C or 90F, consciousness is affected and when the core temperature cools to below 30C or 86F, you die. Hypothermia is not particularly painful as the brain is shutting down at the same time as the body is. In fact, most victims will not realize they are suffering from hypothermia. In cold water, a victim can become hypothermic in under 30 minutes and will die in under 90 minutes. On land, the process of hypothermia typically takes longer. One set of government statistics indicate that approximately 140 Canadians and 800 Americans die from hypothermia each year. However, these stats could be considerably low if there was a way to determine how many drowning victims drowned after loosing consciousness because of hypothermia or how many land victims, particularly in wilderness settings, met with fatal accidents because of a loss of capability due to hypothermia.

Even though the lake we were on was near freezing, the adrenaline rush of hitting the water made any shock from the cold water pass quickly. In fact, all those swimming lessons came back at me and, after kicking my rubber boots off, I swam quite easily in heavy clothes and put on one of the life jackets floating nearby and then pitched a couple more over to my friends. At that point I was only 200 m from shore and debated keeping going to dry land. Then the standard “stay with the boat” line kicked in and we all swam back to the boat (more on that line to come). We were all safe and sound, nobody had drowned, we had life jackets on by now and were holding on to a boat with enough floatation to keep us above the waves even though it was full of water and nobody could get back in. Looked like all we had to do was to hold on until the wind blew us over to the far shore. Of course, I was missing some smarts on heat loss and hypothermia...

HYPOTHERMIA (Part 2 of 3) Guest Article by Bush Creatures

The ingredients for a close-up and personal visit with hypothermia had started coming together the moment I left the cabin in the morning to head down to the boat. Staying up too late and getting up too early had left me tired. There was no time for breakfast and not enough time to pay attention to the sky and weather. There was no plan and minimal survival gear if we dumped the boat. I had got away with that kind of inattention a thousand times before, coming back none the wiser. Not this time. I was now holding on to a swamped boat and up to my neck in very cold water.

Hypothermia is simply a loss of body heat to the point where body functions are impaired or stop. Whether geocaching or boating, the formula for loss of body heat is the same: radiation (the body radiates heat into a colder environment), conduction (direct contact between the body and a colder environment. Water takes heat from the body about 25 times faster than air.), convection (cold molecules moving across the warmer body like wind-chill) and evaporation (where heat is lost when liquids turn to gas such as through perspiration or when breathing out warm air on a very cold day). The variables are almost infinite. What is the air or water temperature, how well is the body insulated from cold, wet or wind, how fast is the body losing heat from exertion? What natural insulation and heat sources does the body have?

As we hung on to the boat and tried to guess how long before we would be blown to the far shore, I was a feast for heat loss. Radiation and conduction into the cold water was the number one threat although the cold wind blowing across my face and head and the puffs of my breath in the cold air were also helping. I am not naturally well-insulated and the lack of body fuel (remember that skipped breakfast?) didn’t help. Strangely enough, I didn’t feel cold. Heck, at no point in the incident did I feel particularly scared. I should have been scared. By now I was close to the point of no-return.

Symptoms of hypothermia can vary almost as much as the causes but all relate to loss of body functions. Confusion, weakness, lack of coordination, drowsiness and violent shivering are all early symptoms. The bad news is that it is not always possible to see those symptoms in yourself. My pals were not hypothermia smart either but at some point as we floated along, two of them moved me between them and locked my arms in theirs because I was talking but making no sense and they were afraid I was going to let go of the boat.

The only good news about the high winds that day was an arrival at the far shore in about fifteen minutes. I will never forget how good it felt to feel rock and sand under my feet and then crawl onto dry land. Safe and sound and out of the water. No drowning victim today. Then the violent shivering really kicked in. I got up and stumbled around with enough brain function left to try to make a fire out of the drift wood lying on the shore. I had a lighter and couldn’t even hold it although it was so wet it wouldn’t have fired up anyway. In my mental and physical state, even a water-proof match container was too technologically advanced. A space blanket would have been a great idea but I wouldn’t have been able to take it out of the plastic wrap if I even remembered I had it. Sudden immersion in cold water wearing jeans and a heavy parka hadn’t drowned me in spite of the stupid lack of a life jacket. But I was completely past the point of any attempt at self-rescue.

Hypothermia (Part 3 of 3) Guest Article by Bush Creatures

An individual can take steps to avoid hypothermia but once they have moved past the minor stage of hypothermia, it is up to others to save their lives because it is very unlikely that they can save themselves.


Stages of Hypothermia:

Mild – victim is cold, shivering and may be uncoordinated

Moderate – intense shivering, obvious lack of coordination, possible confusion

Severe – shivering may stop, very poor coordination, confusion. May lead to semi consciousness or unconsciousness, erratic respiration and heart beat

Treatment of Hypothermia:

Be aware of the risk – is the temperature and situation capable of causing hypothermia?

Recognize the symptoms – be aware of your companions’ behavior. Are they hypothermic?

Stop the cause – is shelter needed from the wind and cold? Are dry clothes needed? Remember my decision to stay with the swamped boat? Given what I know now about hypothermia and add the variables like temperature, wind, how long until we reached the far shore, I think I should have swam to shore. Would I have made it, would I have been abandoning my buddies or getting them rescued faster? Tough call. I do know that had I been alone, swimming to shore would have been the only survivable option.

Increase available heat – add clothing, use a sleeping bag or space blanket, provide heat

Provide body fuel – warm drinks (no alcohol, limit caffeine), provide carbohydrates, proteins and fats if the victim is capable of eating and drinking

Seek medical help

As we huddled together on that wind swept shore, soaking wet in an air temperature of around freezing, I was at the end stage of moderate hypothermia. Due to lack of proper planning, we were all in various stages of hypothermia and our options were limited. No shelter, dry clothes or other gear to reduce heat loss, no means of increasing heat and no body fuel. We hadn’t been aware of the risk and we didn’t have the equipment to stop the cause and provide heat and body fuel. Any form of help was miles away.

At this point, we got very lucky. I was the luckiest for traveling with pals who could still get their act together and knew their stuff. If no-one was going to come and get us and we lacked the gear to survive, we had get out of there. Using an ammo can and bailing bucket, we were able to get the boat above water. Then, wonder of wonder, the wet motor started after numerous pulls on the cord. The boat was still half full of water and the waves were still too high but I was hauled to the boat and one of the guys managed to get me across enough of the lake to be in walking distance of the cabin. The other guys willingly stayed back in spite of their own risk because the boat wouldn’t carry their weight. At the time, I was clueless but, since then, I often think of that. What can I say? Thanks.

It was a happy ending. I made it to the cabin and heat and then the other guys got back too. Four wet, cold but alive guys sitting together under a blanket in front of the fireplace. Don’t get much better! From that moment on, I vowed that there was no way that I, my family, my friends or anyone else I travel the trails with would face the life threatening situation of hypothermia without a lot of ammunition to fight back.

There is a good chance that most of us will not face a life threatening situation in the water or woods but it is out there. Add to that, the possibility of encountering someone else needing assistance and it is an obligation to be prepared, to be equipped and to have the skills to respond. I duck hunt several times a year. The fall hunting season normally brings temperatures as low as freezing. I geocache almost every weekend of the year and, for the winter months, in temperatures far below freezing. Even in the spring and fall with above zero temperatures, I can expect to encounter the combination of temperature, wind and wet that can cause hypothermia. I prepare for it.


Plan your geocaching day. Will it be drive-by caches in an urban setting or bush caching? Dress and pack equipment appropriate to the caches. Then don’t deviate from your plans (besides, if you are caching solo, you have already advised a family member or another cacher which caches you are doing, right?).

Sky watch and check the forecast and plan for sudden extremes appropriate to the season. Encountering an unexpected rainstorm or falling in a creek in the spring and fall while wearing light, non-waterproof clothes is great food for hypothermia. Personally, I feel safer from hypothermia bush caching at below zero temperatures because I am always dressed for it and pack the gear necessary to face a geocaching wreck. At warmer temperatures, too many assumptions can get made. While bush caching, I wear or take the clothes needed to survive sleeping out there.


Take what you need to face the worst possible scenario and know how to use it and know it works. There is a wealth of advice on the Web about survival kits. Check it out. Personally I have several caching packs depending on the type of caching I am doing. The precious cargo that caches many trails in the bush with me, packs her own basic kids kit.

Can’t resist a “check your equipment” story. Remember our inability to light a fire on that wind swept shore? Vowing not to put up with that again, I bought several waterproof match containers and then figured that I would check them out. One type is the aluminum kind with the lanyard ring. Once sealed, I had difficulty reopening it while messing around with it in the warm basement. Given memories of violent shivering and lack of coordination while hypothermic, that one got tossed. Then I tested the plastic ones. Easier to open but two out of four of them leaked when I submerged them under a brick in the kitchen sink. Whoops? That was easily solved with a bit of waxy, leather boot waterproofing in the threads of the container top but I’m glad I found that out in the kitchen sink and not when I really needed fire.

I have found some brand new survival whistles to be defective when taken straight from the bag. We used to pack a few glow sticks until I discovered that they won’t work after cracking at the bottom of the pack. How often do you check your flashlight? For the sake of the couple of dollars, next time you are on the trails in cold weather, sacrifice a space blanket by trying it. How warm are they? What’s the best way to wrap them around yourself or someone else for maximum warmth.


While on the trails, look out for potential hypothermia hazards. A fall into a beaver pond on a crisp fall day can get you every bit as hypothermic as my adventure on the lake. We only cross beaver dams or ice or other water hazards if we know we can survive an unplanned soaking. By the way, how dry will those spare clothes in your larger, long distance bush pack stay when you fall in? I love orange garbage bags. They keep our stuff dry, they can be used as raincoats, signals or picnic blankets and always good for CITO.

Cache In A Group

One cacher on the trails means a do-it-yourself plan for survival. Two cachers doubles the survival options but means one lonely, disabled cacher while the other cacher heads out alone for help. Three cachers means the victim has support but the other cacher still goes it alone while getting out to seek rescue. Four cachers and more is perfection! Do kids count as cachers? Of course. My rules with Bush Girl are her safety is #1. Don’t follow Bush Dad through the ice to rescue him but following #1 first, then follow #2 if you can, help your caching partner. If #1 and #2 work, then #3 is stabilize your partner in that space blanket and those dry clothes and then #4, get help fast.


If tech has provided us with the ability to use multi-billion dollar military satellites to find peanut butter jars and ammo-cans in the woods, it has also provided us with cell-phones and radios. Batteries good and are the electronics water-proofed in double zip lock bags? Can clever little Bush Girl call 911 and give them a good description of our location? Of course she can. She has her own basic etrex and knows how to use it and knows how to use the cell-phone and our local air ambulance service has a GPSr too. Give them our coords and wave that orange garbage bag, Bush Girl!

General Geo-Caching Safety

Can’t resist repeating my own geo-caching safety creed, particularly for bush caching:

Travel in a group or let some-one know the caches you are doing and a call-for-help time if you have not returned.

Mark your vehicle as a waypoint.

Carry spare batteries for the GPSr and pack a non-electronic compass (compasses don’t run out of batteries.) The lanyard on my Garmin has an attached compass and working whistle.

Dress right for potential weather.

Pack the right survival gear and know how to use it.

Be aware of potential wrecks in your cache hunt such as hypothermia and other dangers and plan for them.

Stay tuned to your surroundings. Look up for leaning trees, look around for potential falls while you are looking down at your GPSr or looking for the cache.


This is an overview of hypothermia from the angle of a victim not an expert. Googling hypothermia on the internet will provide a wealth of additional information. In serious hypothermia situations, consult medical advice. Then again, with some basic common sense and some basic knowledge on avoiding hypothermia, you may never have to experience or treat hypothermia.

Thanks to Johnnygeo for the safety page.

Happy and safe caching!

Bush Creatures