11.04 Frostbite and Frostnip
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agk's Library of Common Simple Emergencies

Presentation
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Frostnip occurs when skin surfaces such as the 
tip of the nose and ears are exposed to an 
environment cold enough to freeze the 
epidermis. These prominent exposed surfaces 
become blanched and develop paresthesias and 
numbness. As they are rewarmed, they become 
erythematous and at times painful.

Superficial frostbite can be either a partial 
or a full thickness freezing of the dermis. The 
frozen surfaces appear white and feel soft and 
doughy. With rewarming these areas will become 
erythematous and edematous with severe pain. 
Blistering will occur within 24-48 hours with 
deeper partial thickness frostbite.

What to do:
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- When there is no longer any danger of re- 
    exposure and re-freezing, rapidly warm the 
    affected part with heated blankets (warm 
    hands in the case of frostnip) or in a warm 
    bath (38-40 degrees C).
- A strong anesthetic such as meperidine 
    (Demerol) or morphine may be required to 
    control pain.
- When blistering occurs, bullae should not be 
    ruptured. If the blisters are open, though, 
    they should be debrided and gently cleansed 
    with povidone-iodine and normal saline. 
    Silvadene cream may be applied, followed by 
    a sterile absorbent dressing.
- Patients should be provided with follow up 
    care and warned that healing of the deeper 
    injuries may be slow and produce skin that 
    remains sensistive for weeks. In addition, 
    there may be permanent damage to finger- 
    nails, long term paresthesia, and permanent 
    cold sensitivity.

What not to do:
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- Do not warm the injured skin surface while in 
    the field if there is a change that re- 
    freezing will occur. Re-exposing even 
    mildly frostbitten tissue to the cold 
    without complete re-warming can result in 
    additional damage.
- Do not rub the injured skin surface in an 
    attempt to warm it by friction: this can 
    also create further tissue destruction.
- Do not allow the patient to smoke. Smoking 
    causes vasoconstriction and may further 
    decrease blood flow to the frostbitten 
    extremity.
- Do not confuse frostnip and superficial 
    frostbite with deep frostbite. Severe 
    frostbite, when the deep tissue or 
    extremity is frozen with a woody feeling 
    and lifeless appearence, requires inpatient 
    management and could be associated with 
    life-threatening hypothermia.

Discussion
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Frostbite is more common in persons exposed to 
cold at high altitudes. The areas of the body 
most likely to suffer are those farthest from 
the trunk or large muscles: ear lobes, nose, 
cheeks, hands and feet. Touching cold metal 
with bare hands can cause immediate frostbite, 
as can the spilling of gasoline or other 
volatile liquids on the skin at very low 
temperatures. Of course, prevention is the best 
"treatment" for frostbite. Heavily insulated, 
waterproof clothing gives the best frostbite 
prevention.

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 from Buttaravoli & Stair: COMMON SIMPLE EMERGENCIES
 Longwood Information LLC 4822 Quebec St NW Wash DC
 1.202.237.0971 fax 1.202.244.8393 electra@clark.net
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