Extreme Cold, Wind Chill Pose Dangerous Health Risks

Holmes advises spending as little time as possible outdoors and taking the following steps.

If you need to be exposed to extreme cold longer than 10 minutes:

• wear several layers of loose clothing to better insulate your body; tight clothes reduce blood circulation
• wear a warm winter jacket and warm pants or long underwear 
• protect ears, head, face, hands and feet with insulated boots, wool socks, a warm hat, mittens and a scarf or mask that covers most of your face
• warm your body from the inside with hot liquids, such as soup, hot chocolate, coffee or tea
• keep your car winter-ready with a full tank of gas, extra blankets and clothes in case you get stranded and have to wait for help

Frostbite can set in quickly in frigid weather, largely due to the wind chill, notes Holmes.

With 15 mph winds, for example, body tissue can start to freeze in 30 minutes when the temperature is zero degrees Fahrenheit and in 10 minutes when the temperature drops to minus 20.

Frostbite results in a loss of feeling, such as numbness or tingling; aching; and loss of color, usually in the toes, fingers, nose, ears, cheeks and chin.

It can permanently damage body tissue and, in severe cases, require amputation.

Never rub an area of the body that may have frostbite, Holmes advises, as skin damage may result.

Hypothermia occurs when the body loses heat faster than it can produce it. The body will try to preserve heat to the vital organs — the heart, lungs and brain — by constricting blood vessels everywhere else. Blood pressure and heart rate increase. As the temperature drops, electrical activity in the brain and heart slows.

Multiple physical and mental symptoms result, including uncontrollable shivering, rapid heart rate, increased need to urinate, confusion, drowsiness, slurred speech, loss of coordination, exhaustion and memory loss.

Eventually, victims may experience poor decision-making — which may cause them to stay outside rather than seek warmth — and coma.

Holmes cites several factors that cause hypothermia to occur more quickly, including:

• age: Babies and young children will lose more heat because their heads are bigger relative to their bodies, and people lose a lot of heat through the head, Holmes says. Older people are more vulnerable because the body’s ability to regulate temperature may lessen with age.
  
• alcohol: Alcohol alters the body’s protective response to cold, causing vasodilation of the peripheral blood vessels, which means vital organs will get colder faster as blood circulates. It also produces a flushing feeling or false sense of warmth, which may lead people to remove clothing. In addition, even mild intoxication may affect judgment.
  
• wetness: Water conducts heat away from the body 25 times faster than air, Holmes explains. According to the U.S. Coast Guard, immersion in 33-40 degree water will likely cause exhaustion or unconsciousness in 15-30 minutes and death in 30-90 minutes.

Conversely, increased body fat adds extra insulation and prolongs the time it takes for hypothermia to occur — one of the few benefits of obesity, notes Holmes.

It’s best to keep the elderly, the very young and those with a mental illness that impairs judgment indoors during cold winter blasts, Holmes advises. 

Older people may have mobility problems that make it difficult to get to a warm place. They also may have medical problems or be on medications that affect the regulation of body temperature. 

Children and individuals with dementia or mental illness may not have the judgment to dress properly in cold weather or to get out of the cold when they should.

People with heart and lung diseases are especially vulnerable to subfreezing temperatures, Holmes adds.

Cardiovascular responses can trigger a heart attack and — in severe hypothermia — ventricular arrhythmias.

Because the airway tends to narrow in cold weather, breathing becomes more difficult, affecting those with asthma and chronic obstructive pulmonary disease, including emphysema and chronic bronchitis.

Cold weather also exacerbates Raynaud’s disease, a condition that limits blood circulation to certain areas of the body, such as the hands, causing numbness and pain.

In general, it’s a good idea to check up on relatives and friends to make sure they are warm enough, especially if they live alone, says Holmes.