Middle Tennessee is entering yet another windchill advisory — meaning it will feel like sub-zero temperatures outside. That means even higher risk for frostbite and hypothermia.
Dr. Marshall Hall, the chief of emergency medicine at TriStar Skyline, said layering up and limiting exposure is always a good idea, but given the frigid temperatures this week, he calls those protective measures essential.
“You may only have to be outside for 30 minutes or an hour before you start getting frostbite in your fingertips,” he said. “Whereas if it’s 30 degrees, it may take a couple of hours.”
Frostbite
Frostbite tends to show up on the nose, fingers and toes. Those are some of the farthest points from the body’s core, and they are more likely to be exposed to wind. Hall said happens when the water in our skin starts to freeze.
“It is actually crystals forming inside our cells that then cause damage to those cells,” he said. “And if it’s extensive enough, that can be irreversible.”
He said frostbite requires exposure to freezing cold.
Hypothermia
Hypothermia can develop at warmer temperatures, so even more people are at risk than it seems.
“Especially for elderly patients that may not have great access to heat,” Hall said. “So, if they’re in a fairly cool house but not even below freezing for, you know, several hours, then we can see some hypothermia from that. We also see a lot of hypothermia from our unhoused population that are outside. And so even, you know, even if it’s 20 or 25 degrees outside, that there’s some risk there.”
Hall said hypothermia affects several organ systems in the body, but the brain is one of the first to become noticeable.
“One of the early signs of hypothermia is actually confusion,” he said. “People can become more sedate. They may even appear intoxicated because of their their core body temperature is falling.”
That’s during the early stages of hypothermia. As it progresses, people can become comatose.
The Centers for Disease Control and Prevention says that in addition to the comatose state, people with hypothermia can have a pulse so weak it seems like they’re dead.
“Perform CPR, even if the person appears dead,” the agency’s tip sheet states. “CPR should continue until the person responds or medical aid becomes available. Keep warming the person while performing CPR. In some cases, hypothermia victims who appear to be dead can be successfully resuscitated.”
Hall said the circulatory system takes a hit. The heart can struggle to keep a consistent rhythm, triggering lethal cardiac arrest.
Layering and bundling up can protect against both frostbite and hypothermia, but given how cold it has been this week and will be this weekend, it’s a tough battle.
“Even if you were to layer up a lot, it is hard to to fight off temperatures of zero,” Hall said.
Staying warm inside is a safer bet — for those who have the opportunity.
“Obviously, there are individuals in our community that are unhoused or don’t have electricity or heat on in their house,” Hall said. “And if we know of those people, and we can step in and do something to have them come inside to a warming shelter or inside our house, that is also beneficial. So, so check on those loved ones and those neighbors that you think may be at risk.”
Winter falls
Once the worst of the weather has passed — or once their cabin fever gets bad enough — Tennesseans will face the next big concern: falling.
“There’s still ice on the sidewalks or ice in the street,” Hall said. “Without fail, we will see a spike in people falling and having injuries, you know, broken wrists, broken ankles, broken hips, head injuries, things like that from the ice that remains.”
Again, he says to check in on loved ones and neighbors who are at higher risk, like those with mobility issues.