The question: I've been spending more time outside shovelling and have noticed that my fingers turn cold and painfully prickly. Is this frostbite? And what's the best way to treat it?
The answer: With severe winter weather hitting Canada, frostbite is a real risk that can put a damper on our time outdoors.
Frostbite can occur when our body is exposed to subzero temperatures, which causes the skin and underlying tissues to freeze. It most commonly affects the smaller extremities such as the hands, feet, nose and ears. With prolonged exposure to low temperatures (but only a few short minutes on very cold days) ice crystals can form in the skin and deeper tissues. These crystals can damage the skin and surrounding structures as well as interfere with blood flow to the affected areas.
The severity of frostbite varies based on external and personal factors. External factors include the length of exposure to the cold, windchill and temperature. Personal factors include the type of clothes worn (tight, wet clothes decrease the temperature near your skin), age (those over 65 and young children are at higher risk) and alcohol consumption that can impair your perception of cold temperatures and also cools the body faster.
Mild frostbite, also known as frostnip, involves superficial change in the skin, such as redness and the sensation of cold. If you remain exposed to low temperatures, the symptoms can progress to prickling and numbness. It sounds like you may have developed frostnip. However, once you warm up, the good news is that frostnip generally reverses itself without any consequences.
The next stage of frostbite, known as superficial frostbite, involves ice crystal formation. The skin remains soft but can feel very cold and takes longer to warm up and return to its normal state. In time, if you do not warm up and the skin remains exposed, this can progress to severe frostbite which involves the deeper tissue layers. Symptoms can rapidly progress to numbness, increasing pain, and blistering. The skin's texture can also change from soft to hard and its colour can go from red to pale to black.
The key to treating frostbite is reversing the ice crystal formation and blood vessel damage. This is done by warming the skin and decreasing inflammation. If you're still outside, tuck your hands into your armpits or cover your ears or nose with a hat or scarf. Get out of the cold as soon as possible and remove any wet clothing when you're inside.
Place the frostbitten area in warm water (40-42 C) for 15 to 30 minutes. It's tempting to warm up over a fireplace or stove but you could be putting yourself at rist of burning since it's difficult to detect extreme heat when you skin is numb and frostbitten. If your feet are affected, avoid walking to prevent further damage and pain.
If you continue to experience symptoms or any signs of severe frostbite such as increasing pain, swelling, fever, loss of sensation or blistering , seek medical attention immediately as the damage to the skin and nerves can be permanent if left untreated.
Dr. Sheila Wijayasinghe is the medical director at the Immigrant Womens' Health Centre, works as a staff physician at St. Michael's Hospital in their Family Practice Unit and at Hassle Free Clinic, and established and runs an on-site clinic at Women's Habitat Shelter in Etobicoke.
Click here to submit your questions. Our Health Experts will answer select questions, which could appear in The Globe and Mail and/or on The Globe and Mail website. Your name will not be published if your question is chosen.
The content provided in The Globe and Mail's Ask a Health Expert centre is for information purposes only and is neither intended to be relied upon nor to be a substitute for professional medical advice, diagnosis or treatment.