How long can a person survive in sub-zero temperatures?
With a polar vortex sweeping the coldest air in a generation across a large swath of the country, officials are concerned about seeing more tragedies like the one that claimed the life of a young man in Minnesota last weekend.
Police say 22-year-old Ali Gombo was found dead outside a home in Rochester, Minnesota, in freezing cold temperatures and likely died from hypothermia. He'd been dropped off by friends after a night out at a bar but didn't have keys and the doors and windows were locked, CBS Minnesota reports. Experts say it highlights the life-threatening dangers of sub-zero temperatures.
"Hypothermia is a medical emergency when your body loses heat faster than it can produce it. As your body temperature drops, your heart, brain, and internal organs cannot function. Without aggressive resuscitation and rapid rewarming, you will ultimately not survive," explains Dr. Robert Glatter, an emergency physician at New York's Lenox Hill Hospital.
A neighbor found Gombo's body the next morning, along with footprints around the home and smeared blood on the doors. Pieces of Gombo's clothing were also found in the yard. Stripping off clothing is a strangely common occurrence in later stages of hypothermia — due to nerve damage and mental confusion, a person may feel like they're burning up rather than freezing and begin taking off their clothes and shoes. The phenomenon even has a name: "paradoxical undressing."
Hypothermia starts setting in when a person's body temperature drops from the normal 98.6 degrees F to about 95 degrees. The body begins to shut down. Heart and breathing rates slow down, accompanied by confusion and sleepiness.
"Without rapid rewarming, your heart rate and breathing slows even further, leading to poor circulation to the brain, heart and extremities, which is fatal," Glatter said.
Hypothermia can happen in minutes
Hypothermia can develop in as little as five minutes in temperatures of minus 50 degrees Fahrenheit if you're not dressed properly and have exposed skin, especially the scalp, hands, fingers, and face, Glatter explained. At 30 below zero, hypothermia can set in in about 10 minutes.
Over the next few days, the upper Midwest and Great Lakes will face temperatures 20 to 40 degrees below average, with even more brutal wind chills. Wednesday's high temperature in Chicago is forecast to be 12 below zero. Grand Forks, North Dakota will dip to minus 24 and Minneapolis will hit minus 13. Wind chills will be as low as -65 in parts of Wisconsin and Minnesota, and CBS News' DeMarco Morgan reports a state of emergency has been declared in both states.
How long it takes for someone to freeze to death depends on conditions and the type of exposure, but death can occur in under an hour if conditions are dangerous enough. It can happen even more quickly in a situation such as falling through ice into freezing water.
The elderly and infants are especially vulnerable to hypothermia, according to CBS News' Dr. Tara Narula.
How to protect against frostbite
Another risk in the cold weather is frostbite — when a person's skin freezes. In this extreme cold, exposed skin can be damaged in a matter of minutes.
"This can affect the nose, the chin, the ears, the fingers or the toes. And so you want to keep those covered," Narula advised on "CBS This Morning" last week. She noted mittens may keep your hands warmer than gloves, and she warned, "If you start to notice that you're having numbness or tingling or burning, you want to seek help for that immediately."
Rewarm the skin with warm — not hot — water once you get inside, or use body heat like holding your hands under the armpits. Don't hold freezing limbs over radiators to avoid burning yourself.
The CDC also recommends wearing appropriate outdoor clothing to help you stay safe in the extremely cold weather: a tightly woven, preferably wind-resistant coat or jacket; inner layers of light, warm clothing; mittens, hats, scarves, and waterproof boots.
Avoid traveling when the weather service has issued advisories, and if you have to go out, take a buddy and an emergency kit and always carry a charged cellphone. The CDC also recommends keeping your car's gas tank full to avoid ice in the tank and fuel lines. You don't want to get stranded in this weather.