b'FrostbitehapterChapter The body reacts to extreme cold by shutting down blood vessels to limit the escape of heat. If the vessels are deprived of a warm blood supply, exposed areas such as the fingers, nose or toes tend to freeze up causing frostbite. Contributing factors include cold air temperature, how long the person has been exposed and the wind. Frostbite results from the freezing of tissues causing ice crystal formation and swelling of small blood vessels.Superficial FrostbiteSkin is frozen but the tissues beneath are not.Deep FrostbiteSkin and underlying tissues are frozen.Both conditions are regarded as serious because the frozen water in the tissue cells, swell and produce harmful crystals that destroy the cells. This may lead to permanent damage such as gangrene that often results in amputation to fingers, hands, arms, toes, feet and legs.How to RecogniseAbnormal sensations such as pins and needles.Skin appears pale and waxy, is cold to touch and becomes numb and hard.Skin can become discoloured (yellow, mottled, flushed and eventually black).Upon recovery, the skin may turn red, hot, blistered and become extremely painful.How to ManageDo not apply direct heat or rub vigorously because the affected area is crystallised and likely to sustain further damage and even re-freeze.Be gentle and discreetly remove clothing and any restrictions. Warm the affected parts with the patients own body heat such as placing the affected hands under their armpits.Cover affected nose, ears and face with a towel or scarf to help gradual re-warminguntil sensation and normal colour returns. You may use lukewarm water to help slowly warm up the affected part.Elevate any affected limb to help reduce pain and swelling.Call Ambulance 000.Reassure and rest the patient.Heat and Cold Emergency 141'