During last year's mild winter, seven Allegheny County residents died from hypothermia inside homes where thermostats had been set too low, furnaces were shut off or utility service had been discontinued.
In contrast, only one possible hypothermia death has been reported in the county this season, despite the recent frigid temperatures.
The Allegheny County coroner's office is investigating the possibility that cold temperatures played a part in the death of James Jackson, 19, of Penn Hills, whose body was found Sunday under the Homestead Grays Bridge.
"It's pure conjecture on my part," said coroner Dr. Cyril H. Wecht, of Jackson's death, "but I guess when you live with this from day to day, you come to realize that you darn well better adjust. People have come to realize what they've got to do."
That includes turning the heat on and up, working with utility companies to ensure continued service and checking on neighbors who might need assistance.
In the aftermath of last year's deaths, the coroner's office organized a task force called VANGUARD, for Visit a Neighbor and Give Urgent Assistance to the Retired and Disabled, which includes representatives from law enforcement agencies, community groups, the U.S. Postal Service and others.
"It is something basically to keep people alerted to the fact that there is this potential for elderly people and disabled people to be left alone and we should still be checking on those people," explained Chief Deputy Coroner Joe Domenick.
In hypothermia, core body temperature falls below the normal of 98.6 degrees Fahrenheit. If a person gets colder than 95 degrees, serious problems will occur.
"The first signs of it are some alterations in your consciousness and thinking," said Dr. Donald Yealy, vice chairman of emergency medicine at the University of Pittsburgh School of Medicine. "It can be excitement, but more commonly you'll feel a little sleepy. When that happens you need to get out of that cold and get warmed up again."
The National Institute on Aging tells people to watch for "umbles," namely stumbles, mumbles, fumbles and grumbles, which may indicate that muscles and nerves are being affected by cold.
Biochemical reactions happen most efficiently at normal core temperatures. When exposed to cold, the body will initially work harder to maintain its temperature. But constant cold impairs functions and eventually organ systems begin to fail, said Dr. Harold Sherman, assistant director of Mercy Hospital's trauma and burn centers.
If the ambient temperature is colder than body temperature, hypothermia is possible.
"If we stand outside in bathing suits in 70 degree weather and for some reason we can't maintain our body temperature, we become hypothermic," Sherman said.
People who have difficulty maintaining normal body temperature are at greater risk for hypothermia. That includes the very old or very young, people with circulatory system disease such as heart conditions and diabetes or other chronic medical problems, including lung or neurological problems, and those who have had organ transplants.
The same people are at greater risk for frostbite, which is essentially injury to skin and underlying tissue caused by cold. Fingers, toes, ears and noses are most likely to get frostbitten, Yealy said.
"It comes from prolonged exposure, particularly if the exposure is directly against a cold object or associated with moisture," he said. "It can also happen just being out in the cold and wind."
Sometimes it's hard to know if frostbite has occurred. Frostbitten skin typically appears unusually white because of reduced blood flow, but the color changes may not always be obvious, particularly with dark-skinned people. The injured skin will be hard and cold.
The doctors' advice: If frostbite is suspected, immerse the affected area in warm water. Don't use hot water or open flames because they could cause burns, and don't rub the area. If pain or numbness continues despite rewarming efforts, see a doctor immediately. Amputation is not the only solution.
As Sherman put it, some frostbite injuries are like a toasted marshmallow with pristine flesh beneath a layer of char.
"You can get superficial tissue that's dead and if you just wait it out long enough, you get living tissue underneath that can survive," he said. "That's the waiting game you play. You have to balance that against the risk of infection."
And to those who have felt their icy toes temporarily burn with pain upon coming in from the cold: Don't worry.
"That's probably the mildest version of a thermal insult, but you haven't killed tissue," Yealy said.
He noted that he treats fewer frostbite cases in Pittsburgh than he did in Texas, where he used to work. That's probably because of greater local awareness of cold injuries and their prevention. Conversely, he treats a lot more heat-related illness here in the summer.
According to a UPMC Health System spokeswoman, two people were treated for hypothermia in the last week by the health system. A patient has been at Mercy for a few days for frostbite, which could result in partial amputations of his feet.
Anita Srikameswaran can be reached at anitas@post-gazette.com or 412-263-3858.
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