Frostbite UPDATE - Everything You Need To Know - Dr. Nabil Ebraheim

Educational video describing the condition of frostbite.
Exposure to a temperature below freezing leads to severe soft tissue damage.
How does the body protect itself from cold? Thermoregulation: the body tries to maintain a core body temperature. During extreme cold, the body receives a signal from sensory receptors. For example, these receptors are present in the hands of the feet. The signal will go up to the brain. The posterior hypothalamus is responsible for regulating the body temperature during exposure to cold. The anterior hypothalamus responds to heat.
Once the signal reaches the brain, the brain sends a signal to the body in order to respond to cold temperatures to maintain a core body temperature. This is necessary in order to provide the vital organs with the necessary heat to function properly. Th brain will send a signal to the smooth muscle cells of the blood vessels of the skin and the skeletal muscles. The smooth muscle cells line the arteries and arterioles. During cold, the signal from the brain causes vasoconstriction of the arterioles in the skin which allows the body to shift the blood to more vital areas of the body. At below 0 degrees Celsius, which is about 32 degrees F, the blood vessels close to the skin start to constrict which helps to preserve the core body temperature. Another signal from the brain goes to the skeletal muscles which quickly contracts them causing shivering that helps to keep the body warm. As the body forces the muscles to work (shivering), it breaks down ATP that will also release energy. ATP we converted into ADP and releases free phosphate (P) and energy to warm up the body.
The condition of Frostbite usually affects the hands and feet. When the temp. drops below -2 degrees C, ice crystals are formed in the extracellular fluid. The water moves from the intracellular compartment to the extracellular compartment causing cell dehydration and death. The sensory nerve endings are affected early and the condition can be painless.
Causes of frostbite include:
•Inadequate circulation in below freezing weather
•Inadequate clothing
•Wind chills
•Wet clothes
•Poor circulation
•Tight boots
•Cramped position
•Smoking
•Alcohol use
•Diabetes
•Peripheral neuropathy
•Certain medications such as beta blockers.
Clinical features
The patient may have skin erythema, edema and there may be the presence of mottled skin. In most significant cases there will be blisters present. Blisters may be painless. There are usually two kinds of blisters present:
1-superficial lesions due to partial thickness injury, these are white clear blisters.
2-Hemorrhagic blisters from a deeper lesion which indicates a full thickness injury.
Treatment
•Splint or wrap the involved extremity
•Warm the person and wrap a blanket around them
•Do not rub or massage the involved extremity
•Rapidly warming at a temperature of 40-42 degrees celsius for about 15-30 min
•If blisters are present and if they are clear and white (superficial lesion), then debridement should be done.
•If the blisters are hemorrhagic, drain the blisters but leave the overlooking skin intact. Hemorrhagic blisters are a sign of a deeper lesion and they are usually covering a deep significant injury.
•Amputation for necrotic tissue is always delayed. Need to wait for demarcation of the zone of injury (they used to say if frozen in January, amputate in July) except in severe infection or gas gangrene.
•If the condition of frostbite occurs in children, it may lead to a cartilage or growth plate injury and the child may, later on, develop short digits.

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