Frostbite occurs when the skin an underlying tissue freeze due to being exposed to very low temperatures. You can get it on any part of your body but it most commonly affects your hands, feet, nose, ears and lips.
The severity of the frostbite depends on how low the temperature was. There are two types: superficial and deep frostbite. Superficial frostbite is when only the top layer of skin was affected, so a full recovery is likely. Deep frostbite is more serious. If deeper tissue and blood vessels are affected, the damage may be permanent. In the case of gangrene (dead tissue), amputation may be necessary.
Frostbite happens when your body loses too much heat and damage it caused by its reaction to the extreme cold. Severe weather conditions (such as a blizzard) and unsuitable clothing, especially if it is wet, can have an impact on this.
Blood flow to the extremities, such as the hands, feet, ears, nose and lips, slows down as blood vessels constrict (narrow). This allows an increase in the flow of blood to the body’s vital organs in order to keep the body alive. As blood is redirected away from the extremities, these parts of the body get colder. Fluid in the tissue freezes and ice crystals form. These crystals can rupture cells and damage tissue. If it continues getting colder, the blood vessels with widen further to try to maintain function.
The progressive symptoms of superficial frostbite include:
- Pins and needles, throbbing and aching
- Skin becomes cold, numb and white
- Tingling sensation
- In time, the areas start to feel hard and frozen
- Once in the warm, skin becomes red and may blister – this is painful
- Swelling and itching
- When the frostbite becomes deep, the following additional symptoms are to be expected:
- Skin becomes white, blue or blotchy
As the skin thaws, blood filled blisters form and turn into thick black scabs. At this stage, it is likely that some tissue has died. This is known as gangrene. The tissue may have to be amputated (cut off) to prevent infection.
Can also lead to loss of feeling and lack of sensitivity to the cold
How is it treated?
Preventing frostbite is most important. Do this by staying out from extreme cold and making sure you wear correct clothing so your skin is protected.
If frostbite occurs, it is vital to seek immediate medical attention. If this is not readily available, symptoms can be marginally eased through the following tips:
- If possible, move to a warmer place.
- Replace wet clothing with soft dry clothing to stop further heat loss.
- Warm the body by wrapping it in blankets and protecting the frostbitten parts.
- Do not rub the affected area or apply direct heat (such as a fire or heater) as this can cause further injury.
Re-warming should ideally be carried out under medical supervision, but in any case it needs to be done slowly by immersing the affected area in warm, but not hot, water or warm wet-packs.