Adventure Doc Cold Weather

I grew up in a desert area. Most of the things in here are common sense to those who were raised in a cold environment. Some of these things are not well know, especially to those who live in warm climates. However, living in a warm area makes you enjoy going to colder climates for recreation. This section will help you be a bit more prepared when you find yourself in the cold.

The body’s normal temperature is 98.7 degrees Fahrenheit or 37 degrees Celsius. When the body temperature drops below 95 degrees Fahrenheit or 35 degrees Celsius this is hypothermia (hypo means below in Greek and thermia is temperature). Most of the body’s heat is lost through radiation. This is not radiation from a nuclear plant, but a way of heat transfer. Radiation is loss or gain of heat, through infrared, directly into the environment.

The other three methods of heat transfer besides radiation are convection, conduction and evaporation. Conduction is heat transfer by direct contact and convection is air moving of the surface of something, changing the temperature. Evaporation is water changing from liquid to gas state. So, your body is warm, at 37 degrees Celsius/98.7 Fahrenheit, and the outside temperature is cold, let’s say 0 degrees Celsius/32 degrees Fahrenheit (freezing point of water). The heat will move from your warm body, to the outside air by radiation. In fact, 65% of your body’s heat loss is through radiation. Here’s what to look for with hypothermia:

A body temperature of 32.2 to 35 Celsius (90-95 Fahrenheit) depresses the nervous system and slows pulse rate. Difficulty speaking and walking are common, as is apathy (not caring about what happens). Your body begins to shiver to help itself keep warm. Shivering is your body’s way of moving muscles to increase blood flow to the area, which brings warmth.

27-32.2 Celsius (80-90 Fahrenheit) begins to slow the heart rate even more. Your level of consciousness begins to drop and you feel sleepy. Your heart begins to beat abnormally (arrhythmia) and you see things on an EKG like J waves (Osborne waves) and the QRS complex gets longer. You feel the need to urinate due to the constriction of your body constricting its arteries and veins. At this point, your body cannot rewarm itself and needs help to get the temperature back to normal.

A body temperature of 32.2 to 35 Celsius (90-95 Fahrenheit) depresses the nervous system and slows pulse rate. Difficulty speaking and walking are common, as is apathy (not caring about what happens). Your body begins to shiver to help itself keep warm. Shivering is your body’s way of moving muscles to increase blood flow to the area, which brings warmth.

Hypothermia is a major problem for people in cold weather, especially if they aren’t prepared with good clothing or recognize the signs. Don’t let it happen to you or your traveling partners. I advise the buddy system to keep an eye on each other. If you start seeing signs of hypothermia, begin to help that person warm up. Also remember that if one person in your group is beginning to become hypothermic, others are close and will be shortly.

Some tips for warming up include:

Getting inside a building or shelter, out of the cold and wind (this may be common sense, but when you get really cold, you stop thinking clearly)

Drinking a warm drink (not alcohol) will put that warm fluid into your stomach and intestines. This is the core of your body and does wonders to bring the body temperature up!

Moving around makes your muscles work, which makes heat. You can’t move around forever, but it is a quick fix.

In cold weather, I forget that I need to drink water. I am just not as thirsty as I am in hot weather. That is not very good. Your body may need less water than if it were in hot weather, but it still needs that important water. Also, if you are sweating under your clothing, that counts as water loss from your body. It can be cold outside and if you are dressed warm and active, you will sweat. Remember to replace this water loss! Drinking cold water makes you cold. If you are in a cold environment, try to drink warm water. A trick I use is placing my bottle of water inside my coat, close to my body to let it warm up. After 20 minutes or so, it is ready to drink.

This is the most common type of tissue/skin injury that occurs in cold weather. Simply, the skin freezes. Water, which your body is largely made up of, freezes at 0 Celsius/32 Fahrenheit. Your skin does the same. Ice crystals actually begin to form inside your body’s cells. Why does this happen? Well, your body has a built in mechanism that sacrifices the extremities temperature to keep the core/center warm. Blood gets used to keep the important stuff warm, like heart, lungs, live and kidneys. Frost nip is the beginnings of frostbite.

Frostbite is the advanced condition of frost nip. This is a medical emergency and needs quick treatment. The affected limb or body part will feel like a chunk of wood. There will be a major loss of sensation and feeling. Again, this is a medical emergency and needs a doctor! Rewarming of the area will cause major pain to the victim and frequently will require pain medicine. Never rub the effected area! This will further damage the already injured tissue. The best method for rewarming is to immerse the area into a warm water bath (40 degrees Celsius/104 Fahrenheit) and let it soak. Make sure to handle the are gently! A common mistake is to stop rewarming the area too early. Also, don’t let it refreeze.

Some things that cause frost nip are handling cold objects with your hands, such as metal pipes, wires or going from cold water to the air. Tight clothing, such as tight fitting boots reduce circulation to the area, causing the area to get colde easier. Also, some drugs, such as nicotine, are vasoconstrictors (they tighten up the blood vessels), which decreases circulation. The first signs are a feeling of paresthesia (pins and needles) in the area that is getting too cold. Next, as the skin begins to freeze, waxy looking patches form on the skin and they loose feeling.

To treat this, warm the area up! Put the cold body part under your armpits or your friend’s armpits. Get some gloves on it the hands or socks on the feet. Get to a warm area. If left untreated, this will progress to frostbite, which is a serious condition.

Layering is a common idea to people who live in cold weather. I grew up in a desert area and had to learn about layering the hard way. Layering is using many thinner jackets, coats and shirts to keep warm, rather than one large, thick and bulky layer. The benefits of this are that dressing in layers keeps you warmer and makes it easier to shed a layer if you get too warm. I am known for having an extra layer than most people, because I get cold, easy. I advise having a few warm layers, for insulation, inside your outer layer, which should be wind and waterproof. If you get too hot, take off one of the inner layers and keep the outer layer on top of what is left.

Your body loses most of its heat from the top of your head. This is because there is a large amount of blood that circulates through your brain, without a lot of fat to insulate it from the cold. Anytime you have your blood close to the surface in cold weather, you will get cold quicker. A hat is the perfect solution to this. Why do you think everybody wears one in cold weather? A hat should also be one of the first things you take off, if you are getting to hot. Remember to keep it close by, because you’ll probably get cold in a few minutes without it! Gloves work great too. Your hands are almost always exposed to the cold by carrying something. A good thing to remember is that the further body parts are towards the edge of your body, the colder they get. Hands, feet, ears and the tip of your nose are affected the most. They are just further form your heart and the blood gets colder by the time it gets there.

The old image of the St. Bernard dog rescuing the avalanche victim with a tiny keg of liquor is from a time when people did not know any better. Today, we know that alcohol actually hurts you in cold weather. I know this is not fun, because I enjoy a little shot or two while snowboarding as much as anybody else. Alcohol is a strong vasodilator (opens the blood vessels) and this actually makes you get colder, quicker! As the little arteries and veins open up (dilate), that brings them closer to the surface of your skin and more susceptible to the cold weather. If you want to stay warm, skip the Jagermeister and go for a hot chocolate instead.

The sun’s rays are very powerful and can cause temporary blindness, or at least a lot of pain in the eyes. Everybody knows never to look directly at the sun, for too long, without protection. Well, the sun’s rays reflect off water and snow with a very high intensity. So strong in fact, that it is like looking directly at the sun. Make sure you wear some protective glasses or goggles when in a snowy or icy area!

Also, don’t be fooled into thinking that if the day is cloudy, you can skip the glasses. Not true! If you forgot your glasses and got some "snow blindness", it will not last forever. Heat makes the pain and itchiness worse, so a cool damp cloth over the eyes feels great. Ibuprofen works well to control the pain. Worse cases may require ketorolac opthalmic drops and patching for 24 hours.

Blizzards don’t happen too often where I am from. Still, it is important to know what to do if you find yourself having to live through one, especially if you are trapped in your car, on the way home from work. First, make sure that you are in a safe area and not in the middle of traffic. Stay in the car! If you are on a main road, you’ll soon see help finding you and risking the walk is not worth the chance of injury or death. Hopefully, you will have prepared yourself with some extra blankets and some spare food, for your wait. This might help save you. Turn the engine off. Try to insulate yourself with papers or other things to keep warm. If the cold gets to unbearable, start the car and run the heater, just long enough to take the chill off the air. Also, make sure the tailpipe is not covered with snow. If you need to get out of the car, to cover your engine with a blanket to help keep it warm or to dig out your tailpipe, place a scarf or easily visibly maker on the car, so you can make sure to see it. Never sleep with the engine of the car running. If you feel yourself getting sleepy, turn the engine off and crack a window to help stay awake. Help will find you shortly

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