Frostbite is a type of freezing injury, often accompanied by irreversible tissue damage.
Depending upon the depth of tissue damage, frostbite has been classified into various categories, each of which has its own characteristic clinical manifestations. These include:
Commonly known as “frost nip”. Involves only the superficial part of skin. Presents as:
It is also called “superficial frost bite”. The skin freezes without the involvement of deeper soft tissues. It manifests as:
Third- and fourth-degree frostbite
All the layers of the skin are involved at this stage. Permanent and irreversible tissue damage occurs. Deeper tissues like muscles, tendons, nerves get involved at this point. If left untreated, gangrene might set in, which is a major indication for amputation of the affected organs. It presents as:
The diagnosis of frostbite is made with through the following elements .
The management of frostbite consists of the following .
Irreversible tissue damage is common after frostbite. The mortality rate related with frost bite is about 11%.
Inadequate blood supply to the extremities when exposed to hypothermic environmental conditions as a result of vasoconstriction leading to inadequate tissue perfusion is the basic cause of frostbite.
Various risk factors associated with frostbite are:
Frostbite is common at the altitudes of 11,000-22,000 feet above sea level. It is common in military personnel, mountaineers and in people who engage in activities like high altitude camping. Any racial, gender or age association has not been established as yet.
Body responds to hypothermia by directing the flow of blood from extremities towards the core organs like heart and lungs in an effort to maintain body’s homeostasis. This is done by peripheral vasoconstriction. The body parts likely to be exposed are affected the worst. These include earlobes, tip of nose, chin, fingers, knuckles and toes. Decrease in the flow of blood in the peripheral parts decreases the already falling temperature even further.
If exposure to the cold continues, cellular changes start taking place. Ice crystal formation occurs around the cell membrane . Dehydration of cells causes them to shrink and they begin to die as a result of loss of cellular architecture . Capillary endothelium is also affected which causes leakage of blood out of the blood vessels into the tissue spaces. Blood also begins to clot inside the small vessels, initiating the recruitment of the mediators of inflammation which cause further tissue damage.
Frostbite can be prevented by the following measures   .
Frostbite refers to the damage to the tissues caused by prolonged exposure to cold environment . Exposure to minus 10 °C for even a few minutes is enough to cause frostbite. The parts of the body that are normally exposed to the external environment are likely to be affected the most.
The condition goes unnoticed at first as numbness sets in almost immediately. A form of frostbite, the “trench foot”, is common in soldiers. It is however, a preventable condition that can be avoided with proper precautionary measures.
Initially, it is limited to the superficial layer of skin only but later on, it proceeds to deeper tissues. Tingling is followed by numbness. Skin becomes initially red, then white and yellow, ultimately becoming black. Infection of the affected tissues may lead to the need for amputation. That is why frost bite should be given prompt medical attention.