Frostbite and other snow-related health hazards

Winter sees many of us looking forward to a trip to the snow. Some Mainlanders don't have to go far; it's at the back door! Cold weather is great but there are some problems to watch out for. This article looks at how to minimise the risks and maximise the fun without falling victim to the cold because of:

• chapping 
• chilblains
• frostnip 
• frostbite
• Raynaud’s syndrome attack 
• sun and wind-burn
• snow blindness.

It’s a good idea to wear several layers of clothing, with a waterproof outer layer, to ensure that you remain warm and dry. Thermal undergarments draw any moisture away from the skin and additional layers create pockets of warm air around the body. Layers can also be removed or added as temperatures rise and fall.

Chapping

The cold and wind cause chapping: dry, cracked skin that can be painful. Sometimes the cracks can become deep and infected.

The lips and mouth are particularly vulnerable to chapping as they are most likely to be exposed to the cold and drying wind. Other areas that may get chapped include:

• eyelids
• palms
• knuckles
• folds between the fingers.

To prevent and treat chapping, use a good moisturiser, barrier cream, oil (such as olive oil) or emollient such as petroleum jelly or lanolin on susceptible areas.

Chilblains

Chilblains are itchy, burning red patches that tend to develop on extremities like fingers, toes and earlobes several hours after exposure to the cold. Thought to be related to poor circulation, they seem to affect some people more than others.

The blood vessels in the affected area constrict as they become colder. When they are warmed again – particularly if they are warmed too quickly – a small amount of blood leaks from them, producing the redness and itchy, burning sensations. 

The best prevention is protection against the cold, particularly if you know you have poor circulation or are prone to chilblains.

If any body parts become cold it is best to warm them gradually, rather than by exposure to extreme heat.

Chilblains usually disappear after seven to 14 days. In the meantime, they should be kept warm and dry to protect them from further damage.

Frostnip and frostbite

Frostnip and frostbite are caused by exposure to the cold. The risk of both is increased by:

• wind chill
• high altitude
• hypothermia 
• pre-existing circulatory disorders.

Frostnip can be the precursor of frostbite. It usually affects areas of the body that are exposed to the cold, such as ears, nose, fingers and toes. The skin becomes white and numb or tingly.

Frostbite is a more severe form of frostnip and leads to permanent injury. Ice crystals form in the cells, which expand and then burst, releasing chemicals that damage the flesh. The skin may become swollen and blistered.

To diagnose frostnip and frostbite doctors will check out the appearance of the skin, changes in sensation and any additional risk factors.

Frostnip can be treated with rapid rewarming. It should cause no long term damage, although the skin may become injured more easily if it is exposed to the cold again soon afterwards.

Frostbite should be taken very seriously and medical help is needed as soon as possible.

Frostnip and frostbite animation

Treatment of frostbite:

• remove affected parts from any cold or wet clothing
• attempt rewarming ONLY if further re-freezing is not a possibility
• if rewarming is possible then it should be in water at approximately 40 degrees Celsius with antiseptic solution added if available
• strong painkillers may be needed for the rewarming process, which tends to take approximately an hour
• the affected part must not be used and should be splinted and placed in sterile and protective dressings
• the person should be kept well hydrated and warm
• antibiotics and tetanus prevention may be needed
• the person is likely to be referred to a specialist doctor for more treatment.

Raynaud’s syndrome attack

Raynaud’s syndrome is a circulatory condition usually affecting the hands and feet. Women are seven times more likely to have it than men. A Raynaud’s syndrome attack is often provoked by exposure to the cold. Arteries in the affected part constrict or shut down, dramatically decreasing the blood supply to the area, which goes white then blue.

As the person warms up, the arteries begin to circulate blood again and the part may become red or purple and throb, tingle or burn.

A person with Raynaud’s syndrome needs to be particularly careful to keep his or her extremities warm and dry to prevent an attack.

Read more about Raynaud’s disease.

Sun and wind-burn

The snow reflects up to 80% of the sun’s rays, nearly doubling the risk of sunburn. Wind further exaggerates these effects, drying out the skin and making it more likely to burn.

Prevent sun and wind-burn by applying a high sun protection factor (SPF) sunscreen – 30 or above. Remember to cover the parts that the snow will reflect on:

• your lips
• under and inside your nose
• under your chin
• ears
• around eyebrows.

Treat sun and wind-burn with cooling water, calamine lotion and regular applications of moisturiser. Find out more about the treatment and prevention of sunburn.

Snow blindness

Snow blindness is sunburn that affects the eyes, including the conjunctiva (the moist membrane that coats the surface of the eye and eyelid), the cornea (the transparent dome that covers the surface of the eye) and the retina (the light-sensitive tissue that lines the inner surface of the eye).

At first the eyes may feel dry and irritated. Over the following 12 hours, though, the irritation may develop into:

• red, swollen eyes and eyelids
• extreme irritation of the eyes - feeling like sand is in them
• difficulty opening the eyes or moving them.

Snow blindness can be cumulative: each time you get it, the long term effects are worse. In severe cases the eyes can be permanently damaged.

Prevent snow blindness by wearing UV goggles or sunglasses - particularly those that stop light from the sides - all the time, even when it is overcast. Get more information about protecting your eyes from the sun.

Rubbing the eyes can cause further damage, so it is important to resist the temptation to do this. If symptoms are severe, or cause ongoing visual disturbance, see your doctor.

Snowblindness can be relieved with anaesthetic eye drops. It is important to avoid further exposure to UV light. Sunglasses or goggles are essential.

With the right gear and good protection, you can keep safe and have maximum fun in the snow.

Further information

For more information about being prepared and keeping safe in the snow, visit the ACC website www.snowsmart.co.nz

Original material by everybody and kindly reviewed by Dr Cheryl Tallon, June 2009.