As I write, the DC metro region is again looking at potential winter storms heading its way. Normally, especially after having spent 20+ years in the Washington DC region, I chalk this up to hype by the local meteorologists and news networks seeking to increase viewership. After all, ratings support ad revenue and what better way than the doom and gloom of a weather forecast with the three “b’s” (blizzard, bitter cold, biting winds!). This year, however, we in the Mid-Atlantic seem to be getting more than our fair share of really cold weather. Who had ever heard of the term “polar vortex” prior to this season (outside of comic book villains, of course!)? While all of this cold and snow is great for local ski area snowmaking, it does bring some real risks to health and safety. Given that even the groundhogs have forecast six more weeks of winter, this article provides a brief overview of the signs and symptoms of cold related injuries, how to treat them and how to prevent them.

Brrr…!!!

The adverse effects of cold can be general or acute. General effects are seen as an overall lowering of body temperature — a condition referred to as hypothermia. Normal body temperature is typically in the range of 97.7 to 99.0 degrees F. Mild hypothermia begins when body temperatures drop to below 96 degrees (generally between 90 and 95 degrees). Symptoms include shivering, confusion, lethargy, slurred speech, clumsiness, pale skin and slow or labored breathing. Moderate hypothermia occurs when the body temperature drops to between 82 and 90 degrees. Symptoms are similar to mild hypothermia, but are more pronounced. Shivering may actually stop indicating that the body’s internal warming mechanisms have been overwhelmed and shut down. Severe hypothermia is a true medical emergency and occurs when the core body temperature is lower than 82 degrees. This often results in unconsciousness and can result in a very faint or even indiscernible pulse and/or breathing.

Snow is a skier’s best friend, but don’t forget to dress appropriately for the weather. Photo by M. Scott Smith.

Treatment in all cases of hypothermia involves rewarming the chilled individual. The easiest way in the metro area is to head inside! Gradual warming is best so avoid immersion in hot water (e.g., hot tub) or sudden exposure to heat sources. This can actually shock a hypothermic person or cause burns. Where possible, warm the core using blankets (throw them in the dryer for a few minutes to help warm them up), hot water bottles (careful of water temperature), or heater packs located under the arms, between the thighs or near the neck. Again, be sure to monitor those areas to take care against burns. If you can’t move indoors or find yourself in a remote area, seek whatever shelter may be available (e.g., tent, lean-to, or even a deadfall). Taking in warm fluids can also help, but avoid caffeine and alcohol as those can actually make the situation worse. In extreme circumstances where nothing else is available, you can also use direct body to body contact to warm a hypothermic individual — just be careful not to become a patient yourself!

In addition to warming, be sure to monitor hypothermic patients for secondary issues. Moderate hypothermic patients should seek advanced medical attention in that such cases can suffer from complications including heart arrhythmia or be at risk for heart attack. Severe hypothermia is a true medical emergency and calling 911 is the best course of action, along with getting a person to shelter as quickly as possible. In cases of severe hypothermia, a person with little to no discernable pulse and/or breathing should have CPR administered until more advanced emergency medical care is available.

Frozen body parts

Acute cold injuries typically take the form of frost nip or frost bite. Both are variations of frost bite with frost nip being the mildest form. Signs and symptoms of frost nip include skin that looks pale and feels cold and/or stiff. Fortunately, this is only at the surface and the underlying tissues are not frozen. Skin may swell and itch when rewarmed. Moderate frost bite occurs when exposed skin is allowed to freeze at the surface. Skin will feel hard and stiff and will have a pale or even blue color. While deep tissue is generally not damaged, cells in the skin layers (e.g., epidermis and dermis) will have been damaged. Fluid filled blisters will appear as the affected limbs rewarm. Severe frostbite occurs when the skin and underlying tissue is frozen, including muscles and bone. Skin can appear white, blue or even mottled. As the affected limb or digits rewarm, they can turn black indicating dead tissue.

All frost bite (including frost nip) should be treated carefully. Avoid rubbing or massaging the affected part which can cause more injury. In addition, warming should only occur if you can ensure that the affected limb will stay warm and not be at risk for refreezing, which can exacerbate damage. For frost nip, warm the affected limb by coming inside. If coming inside is not possible, cover the affected limb (e.g., hat for ears, mittens for hands, etc.). You can even tuck affected parts closer to the body core (e.g., hands crossed and under the arms). Coming inside is still the best option before more severe frost bite sets in. For frost bite that is moderate to severe, try to isolate the frozen digits on hands or feet by wrapping them in sterile gauze. Seek shelter indoors and seek medical treatment for rewarming as complications can arise during the rewarming process. In cases of severe frost bite, affected digits may have to be surgically removed to prevent infection (e.g., gangrene) from taking hold and spreading.

Layer, layer, layer!

Of course, prevention of cold injuries is the best method. Dressing in layers provides the best method using materials that have appropriate insulating or wind and water repellency. Starting with a wool or polypropylene base layer is best to help wick moisture away from the body. A subsequent insulating layer (or layers) ensures body heat retention followed by a shell or parka to resist wind and rain or snow. Of course, don’t forget the hat, scarf (to seal the area around the neck) and gloves or mittens. In fact, when given a choice, mittens work better for warmth to keep the fingers together for warmth. Layering the legs and feet are just as important. Long underwear, a layer of insulation and shell pants are a good combination along with wool socks and appropriate footwear.

Finally, a word about moisture - water conducts heat away from the body at a rate about 25% faster than air. This is due to water’s density and its greater energy absorption capabilities. For this reason, its best to not only stay warm, but warm and dry! Using insulating layers that wick aware moisture and an outer layer that is both breathable and waterproof work best. Have fun with the snow, but remember to watch out for the dangers of the cold.