Hypothermia is a direct effect of the cold on health. When a person is exposed to the cold for too long, his or her body may be incapable of keeping the proper temperature to function well. Hypothermia occurs when a person’s oral temperature drops below 35°C.
When hypothermic, the human body can no longer function normally. Hypothermia can lead to serious health risks and even death.
Risk of hypothermia varies according to the temperature felt, meaning the wind chill index. Weather forecasters use the term “wind chill index” to indicate the temperature felt on skin exposed to the cold. In general, the temperature felt is colder than the actual temperature.
Wind chill index
Risk of hypothermia
-10 to -47
Low to moderate risk
If you stay outside for a long time without proper protection
-48 to -54
Serious risk
If you stay outside for a long time without proper protection
-55 and lower
High risk
Danger
Symptoms
The severity of hypothermia depends on the body’s temperature. Hypothermia can be mild, moderate or severe. Symptoms differ depending on the severity of hypothermia.
Severity of hypothermia
Symptoms
Before hypothermia
Oral temperature a little over 35°C
Discomfort
Mild hypothermia
Oral temperature between 32.2°C and 35°C
Chills
Cold ears, nose, cheeks, fingers and toes
Swelling of extremities (fingers, toes) to the point of causing clumsiness
Moderate hypothermia
Oral temperature between 28°C and 32.2°C
Lack of coordination
Difficulty speaking
Confusion
Unusual or abnormal behaviour
Impaired judgment
Rapid pulse and breathing
Severe hypothermia
Oral temperature lower than 28°C
Chills stop
Empty stare
Loss of consciousness
Slow breathing
Respiratory arrest
Cardiac arrest
Death
What to do if you have symptoms
Mild to moderate hypothermia
If you have symptoms of mild to moderate hypothermia, contact Info-Santé 811.
While waiting for Info-Santé instructions:
Shelter yourself from the cold without making any sudden movements.
Gently remove damp or wet clothing.
Cover yourself with blankets and begin by warming up your head, neck, trunk and then groin area (upper thighs).
If you have hot water bottles or electric blankets, place them in your armpits, in the groin area and on your stomach. Be careful not to burn yourself.
If possible, take small sips of a hot and sugary drink that does not contain alcohol.
Do not massage your skin.
Do not smoke or drink alcohol to warm yourself up. On the contrary, smoking or drinking alcohol can lower your body temperature even more.
Severe hypothermia
Severe hypothermia requires immediate medical attention. Anyone with symptoms of severe hypothermia should be taken to emergency or 9-1-1 should be called immediately. While waiting for assistance, you can take the following measures to help the person:
Shelter him or her from the cold without making any sudden movements.
Gently remove his or her damp or wet clothing.
Cover him or her with blankets.
Do not use electric blankets, hot water bottles or direct heat to warm the person up.
Do not massage his or her skin.
If the person is conscious, give him or her small sips of a hot and sugary drink that does not contain alcohol.
Do not allow the person to smoke or drink alcohol; neither will warm him or her up. On the contrary, smoking or drinking alcohol can lower his or her body temperature even more.
Treatment
It is always necessary to see a doctor or another health-care professional to treat hypothermia, whether it’s mild, moderate or severe.
Complications
Severe hypothermia can be fatal.
Protection and prevention
You can take certain precautions to prevent experiencing the effects of cold temperatures. You will find advice on how to protect yourself and your loved ones during periods of extreme cold on the Preventing the harmful effects of cold temperatures page.
People at risk
Certain people are more at risk of suffering from the effects of extreme cold:
Newborns and infants
People aged 65 and over
People with reduced mobility
People with reduced autonomy
People with chronic illnesses, such as:
Cardiac or respiratory failure
Asthma
Diabetes
Malnutrition
Certain neurological disorders
People with mental illness
Homeless people
People who work outside
Some medications make people more sensitive to the cold. People who take medication for chronic illnesses or other diseases should seek information on the subject from a health-care professional.
