We’re in for a cold week in the 705 with temperatures expected to dip to -32 degrees in some regions. I can practically hear some people yelling that this is Canada in the winter, and we should be used to it. Used to it or not, the effects of exposure to the cold can set in quicker than you think, and it can be life threatening. In fact, even prolonged exposure to normal winter temperatures can affect the heart, brain and other vital organs.
When exposed to the cold, the body can lose heat faster than it’s produced. Studies show that about 60% of heat loss occurs through radiation – heat simply radiates away from the body into the surrounding air. The body also can lose heat when a person touches a cold object, such as the steering wheel of a car, or cold wind touches the body. Heat can also leave the body through evaporation, such as when someone sweats while running, shoveling snow or otherwise exerting themselves in cold weather.
When air temperatures drop, blood vessels constrict to prevent heat loss and to keep more blood around the body’s core. Blood is moving away from the periphery to this area, which is why fingers and toes get cold. However, this increases blood pressure, and high blood pressure can lead to a heart attack or stroke. Extreme cold also may cause blood to thicken and become more prone to clotting, which also raises the risk of heart attack and stroke.
Cold also poses risk to people with asthma, chronic lung disease, or other respiratory conditions or illnesses because cold, dry air irritates the airways. This leads to greater inflammation and causes muscles around the airways to constrict, which can lead to wheezing, coughing, shortness of breath or a burning feeling in the chest, especially during exertion.
The Simcoe Muskoka District Health Unit has released some important information about how cold weather impacts your body and how to protect yourself.
HYPOTHERMIA
Hypothermia occurs when the body loses heat faster than it can generate it, leading to a core body temperature that is too low (less than 35ºC) for regular functioning of the body. Hypothermia affects brain and muscle functions, making it difficult for a person to think clearly or move well.
Signs and symptoms of hypothermia include:
- Shivering (in later stages of hypothermia, shivering can decrease or stop)
- Pale skin (in later stages, skin can turn bluish)
- Confusion (e.g. difficulty thinking, poor judgement, and memory loss)
- Difficulty speaking (e.g. slurred, mumbled speech)
- Difficulty moving (e.g. stumbling or uncoordinated movements and fumbling objects)
- Drowsiness or exhaustion
Symptoms may be more subtle in older adults. For infants, look for cold reddish skin and low energy.
If you suspect that someone has hypothermia, seek medical attention immediately. Move the person to a warm location. Remove wet clothes and change into dry clothes if possible. Cover the person with several layers of blankets to warm them slowly. If the person is alert, offer them a warm drink (non-alcoholic and non-caffeinated). If the person is unconscious, lay them down and avoid shaking or handling them roughly.
FROSTNIP
Frostnip is a cold weather injury that occurs when skin is exposed or not properly protected from cold temperatures and wind. It happens before frostbite begins. Frostnip can progress into frostbite if cold exposure is prolonged. Recognizing frostnip is important, so that actions can be taken to prevent frostbite.
Signs and symptoms of frostnip include:
- Skin appears red (it may start to turn white)
- Skin may sting, prickly, or burn (in later stages, skin may feel tingly or numb)
- Skin will feel soft (not firm or waxy)
If you suspect you or someone else has frostnip, move to a warm location and slowly warm the affected area. Put on warm, dry clothes. Rewarm the skin using body heat, or warm (not hot) water. Do not rub or massage the affected areas. This can cause more damage. Do not apply direct heat, such as a heating pad, heat lamp, or the heat of a stove, fireplace, or radiator for warming; this will help to avoid burning the skin. It is common to feel tingling or burning as the skin rewarms. If blisters form after cold exposure, this may indicate frostbite. If this occurs, seek medical attention.
FROSTBITE
Frostbite is a skin injury, caused by freezing. Frostbite occurs when skin is exposed or not properly covered or protected from cold temperatures and wind chill. The most common body parts to get frostbite include the nose, ears, cheeks, chin, fingers, and toes. Frostbite can permanently damage body tissues, and in severe cases, lead to amputations. Once a part of the body has had frostbite, it is more likely to happen again.
Signs and symptoms of frostbite include:
- Skin appears white or grayish-yellow in colour
- Skin feels unusually firm or waxy and cold to the touch
- Pins and needles feeling, followed by numbness
- Blisters, in severe cases
If you suspect that you or someone else has frostbite, move to a warm location and remove wet clothes. If a warm shelter is not available and there is a possibility that skin will refreeze, do not try to warm frostbitten skin. Gently warm up the affected areas using body heat (e.g. put fingers in your armpits or place a warm hand over your nose or cheeks). Do not rub or massage the affected areas. This can cause more damage. Do not apply direct heat such as a heating pad, heat lamp, or the heat of a stove, fireplace, or radiator for warming. Since frostbite makes an area numb, you could burn your skin. Avoid walking on frostbitten toes or feet.
Seek medical attention if the skin is pale gray or waxy, there is swelling or blistering, or if there is pain. Medical help should also be sought if the normal skin colour or sensation does not return quickly.
Be aware:
- Know the weather conditions before going outside. Check the forecast, weather alerts, and travel advisories.
- Consider shortening outdoor play for children when temperatures are between -20ºC to -25ºC (with or without wind chill) and keep children indoors if temperatures reach or drop below -27ºC (with or without wind chill). More advice about winter safety for your children can be found at Caring for Kids, developed by the Canada Paediatric Society.
- Always be alert for signs of hypothermia, frostbite, and frostnip. If you experience these symptoms when exposed to the cold, move indoors, get warm, and seek medical attention:
- Respiratory: shortness of breath, wheezing and coughing
- Cardiovascular: chest pain and arrhythmia
- Circulation: colour change of finger and toes, pain, numbness, and tickling sensation in extremities
- Muscle: pain, stiffness, swelling, restricted movement, weakness
- Skin: itching, pale
Cover up:
- Dress warmly and cover exposed skin (exposed skin can become frostbitten in as little as 30 seconds in extreme cold).
- Wear a hat, gloves/mittens, and a neck warmer or scarf to prevent heat loss, and protect the fingers, chin, lips, nose, and cheeks.
- Wear waterproof winter boots and warm socks (e.g. wool socks).
- Dress in layers to include an:
- Inner layer: clothing should have ‘wicking’ properties to remove moisture (sweat) from the skin;
- Middle layer: should be warm, insulating layer (e.g. sweater) to keep you warm and prevent heat loss; and
- Outer layer: should be wind-resistant to prevent cold air from getting inside the layers.
- Wear sunglasses, lip balm, and sunscreen to protect your skin from ultraviolet radiation (UV rays) causing sun burns, and skin and eye damage. See Health Canada’s sun protection through the seasonsfor more information.
- Wear a face mask and googles if you are participating in winter activities such as skiing, snowmobiling, and skating to protect your face from frostbite and windburn.
- Stay dry, since wet clothing chills the body rapidly.
- If you start to sweat or are getting too warm, try to cool off (e.g. resting, removing some extra layers of clothing). Excess sweat can increase heat loss.
- If your clothes get wet, change into dry clothes as soon as possible.
Warm up:
- Drink warm fluids (e.g. non-caffeinated tea, water, milk). Avoid caffeinated or alcoholic beverages as they can cause your body to lose heat more quickly.
- Take shelter from the wind to reduce wind chill exposure.
- Keep moving and limit time spent standing or sitting. Moving will keep your blood flowing and maintain your body heat.
- Warm up by taking regular breaks in a heated building.
Take care:
- Check in on neighbours, friends, and family (e.g. call, videocall, text) who may be at risk during extreme cold weather events.
- Frequently check in with children and ensure they remain properly dressed.
- Notify friends and family of your location when going on outdoor activities, such as hiking and skiing.
Travel safety:
- Avoid travelling on ice-covered roads, overpasses and bridges, or when visibility is poor.
- Have a winter emergency car kitbefore you leave and bring warm clothing.
- Never pour water on your windshield to remove ice or snow; shattering may occur.
- Do not rely on a car to provide sufficient heat; the car may break down.
One note we wanted to add – please look after your pets and do not leave them outside in these freezing temperatures. Like people, cats and dogs are susceptible to frostbite and hypothermia and should be kept inside.
