Frostbite is a
skin
Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation.
Other animal coverings, such as the arthropod exoskeleton, have different ...
injury
Injury is physiological damage to the living tissue of any organism, whether in humans, in other animals, or in plants.
Injuries can be caused in many ways, including mechanically with penetration by sharp objects such as teeth or with ...
that occurs when someone is exposed to extremely low temperatures, causing the
freezing
Freezing is a phase transition in which a liquid turns into a solid when its temperature is lowered below its freezing point.
For most substances, the melting and freezing points are the same temperature; however, certain substances possess dif ...
of the skin or other tissues,
[ commonly affecting the ]finger
A finger is a prominent digit (anatomy), digit on the forelimbs of most tetrapod vertebrate animals, especially those with prehensile extremities (i.e. hands) such as humans and other primates. Most tetrapods have five digits (dactyly, pentadact ...
s, toe
Toes are the digits of the foot of a tetrapod. Animal species such as cats that walk on their toes are described as being ''digitigrade''. Humans, and other animals that walk on the soles of their feet, are described as being ''plantigrade''; ...
s, nose
A nose is a sensory organ and respiratory structure in vertebrates. It consists of a nasal cavity inside the head, and an external nose on the face. The external nose houses the nostrils, or nares, a pair of tubes providing airflow through the ...
, ear
In vertebrates, an ear is the organ that enables hearing and (in mammals) body balance using the vestibular system. In humans, the ear is described as having three parts: the outer ear, the middle ear and the inner ear. The outer ear co ...
s, cheek
The cheeks () constitute the area of the face below the eyes and between the nose and the left or right ear. ''Buccal'' means relating to the cheek. In humans, the region is innervated by the buccal nerve. The area between the inside of th ...
s and chin
The chin is the forward pointed part of the anterior mandible (List_of_human_anatomical_regions#Regions, mental region) below the lower lip. A fully developed human skull has a chin of between 0.7 cm and 1.1 cm.
Evolution
The presence of a we ...
areas. Most often, frostbite occurs in the hands and feet. The initial symptoms are typically a feeling of cold and tingling or numbing
Hypoesthesia or numbness is a common side effect of various medical conditions that manifests as a reduced sense of touch or sensation, or a partial loss of sensitivity to sensory stimuli. In everyday speech this is generally referred to as num ...
.[ This may be followed by clumsiness with a white or bluish color to the skin.][ Swelling or blistering may occur following treatment.][ Complications may include ]hypothermia
Hypothermia is defined as a body core temperature below in humans. Symptoms depend on the temperature. In mild hypothermia, there is shivering and mental confusion. In moderate hypothermia, shivering stops and confusion increases. In severe ...
or compartment syndrome
Compartment syndrome is a serious medical condition in which increased pressure within a Fascial compartment, body compartment compromises blood flow and tissue function, potentially leading to permanent damage if not promptly treated. There are ...
.[
People who are exposed to low temperatures for prolonged periods, such as winter sports enthusiasts, military personnel, and ]homeless
Homelessness, also known as houselessness or being unhoused or unsheltered, is the condition of lacking stable, safe, and functional housing. It includes living on the streets, moving between temporary accommodation with family or friends, liv ...
individuals, are at greatest risk.[ Other risk factors include drinking ]alcohol
Alcohol may refer to:
Common uses
* Alcohol (chemistry), a class of compounds
* Ethanol, one of several alcohols, commonly known as alcohol in everyday life
** Alcohol (drug), intoxicant found in alcoholic beverages
** Alcoholic beverage, an alco ...
, smoking
Smoking is a practice in which a substance is combusted, and the resulting smoke is typically inhaled to be tasted and absorbed into the bloodstream of a person. Most commonly, the substance used is the dried leaves of the tobacco plant, whi ...
, mental health problems, certain medications, and prior injuries due to cold. The underlying mechanism involves injury from ice crystals and blood clot
A thrombus ( thrombi) is a solid or semisolid aggregate from constituents of the blood (platelets, fibrin, red blood cells, white blood cells) within the circulatory system during life. A blood clot is the final product of the blood coagulatio ...
s in small blood vessel
Blood vessels are the tubular structures of a circulatory system that transport blood throughout many Animal, animals’ bodies. Blood vessels transport blood cells, nutrients, and oxygen to most of the Tissue (biology), tissues of a Body (bi ...
s following thawing.[ Diagnosis is based on symptoms.] Severity may be divided into superficial (1st and 2nd degree) or deep (3rd and 4th degree).[ A ]bone scan
A bone scan or bone scintigraphy is a nuclear medicine imaging technique used to help diagnose and assess different bone diseases. These include cancer of the bone or metastasis, location of bone inflammation and fractures (that may not be vis ...
or MRI
Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to generate pictures of the anatomy and the physiological processes inside the body. MRI scanners use strong magnetic fields, magnetic field gradients, and rad ...
may help in determining the extent of injury.[
Prevention consists of wearing proper, fully-covering clothing, avoiding low temperatures and wind, maintaining hydration and nutrition, and sufficient physical activity to maintain ]core temperature
Normal human body temperature (normothermia, euthermia) is the typical temperature range found in humans. The normal human body temperature range is typically stated as .
Human body temperature varies. It depends on sex, age, time of day, exert ...
without exhaustion.[ Treatment is by rewarming, by immersion in warm water (near body temperature) or by body contact, and should be done only when consistent temperature can be maintained so that refreezing is not a risk.][ Rapid heating or cooling should be avoided since it could potentially cause burning or heart stress. Rubbing or applying force to the affected areas should be avoided as it may cause further damage such as abrasions.][ The use of ]ibuprofen
Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that is used to relieve pain, fever, and inflammation. This includes dysmenorrhea, painful menstrual periods, migraines, and rheumatoid arthritis. It can be taken oral administration, ...
and tetanus toxoid
Tetanus vaccine, also known as tetanus toxoid (TT), is a toxoid vaccine used to prevent tetanus. During childhood, five doses are recommended, with a sixth given during adolescence.
After three doses, almost everyone is initially immune, but ...
is recommended for pain relief or to reduce swelling or inflammation.[ For severe injuries, ]iloprost
Iloprost, sold under the brand name Ventavis among others, is a medication used to treat pulmonary arterial hypertension (PAH), scleroderma, Raynaud's phenomenon, frostbite, and other conditions in which the blood vessels are constricted and b ...
or thrombolytic
Thrombolysis, also called fibrinolytic therapy, is the breakdown ( lysis) of blood clots formed in blood vessels, using medication. It is used in ST elevation myocardial infarction, stroke, and in cases of severe venous thromboembolism (massiv ...
s may be used.[ Surgery, including amputation, is sometimes necessary.]
Evidence of frostbite occurring in people dates back 5,000 years. Evidence was documented in a pre-Columbian mummy discovered in the Andes. The number of cases of frostbite is unknown. Rates may be as high as 40% a year among those who mountaineer
Mountaineering, mountain climbing, or alpinism is a set of outdoor activities that involves ascending mountains. Mountaineering-related activities include traditional outdoor climbing, skiing, and traversing via ferratas that have become sports ...
.[ The most common age group affected is those 30 to 50 years old.] Frostbite has also played an important role in a number of military conflicts.[ The first formal description of the condition was in 1813 by ]Dominique Jean Larrey
Dominique Jean, Baron Larrey (8 July 1766 – 25 July 1842) was a French surgeon and soldier best known for his service in the French Revolutionary and Napoleonic Wars. An important innovator in battlefield medicine and triage, Larrey invented t ...
, a physician in Napoleon
Napoleon Bonaparte (born Napoleone di Buonaparte; 15 August 1769 – 5 May 1821), later known by his regnal name Napoleon I, was a French general and statesman who rose to prominence during the French Revolution and led Military career ...
's army, during its invasion of Russia.[
]
Signs and symptoms
Areas that are usually affected include cheeks, ears, nose and fingers and toes. Frostbite is often preceded by frostnip.[ The symptoms of frostbite progress with prolonged exposure to cold. Historically, frostbite has been classified by degrees according to skin and sensation changes, similar to burn classifications. However, the degrees do not correspond to the amount of long term damage.] A simplification of this system of classification is superficial (first or second degree) or deep injury (third or fourth degree).
First degree
* First degree frostbite is superficial, surface skin damage that is usually not permanent.
* Early on, the primary symptom is loss of feeling in the skin. In the affected areas, the skin is numb, and possibly swollen, with a reddened border.
* In the weeks after injury, the skin's surface may slough off.
Second degree
* In second degree frostbite, the skin develops clear blister
A blister is a small pocket of body fluid (lymph, serum, plasma, blood, or pus) within the upper layers of the skin, usually caused by forceful rubbing (friction), burning, freezing, chemical exposure or infection. Most blisters are filled ...
s early on, and the skin's surface hardens.
* In the weeks after injury, this hardened, blistered skin dries, blackens, and peels.
* At this stage, lasting cold sensitivity and numbness can develop.
Third degree
* In third degree frostbite, the layers of tissue below the skin freeze.
* Symptoms include blood blisters and "blue-grey discoloration of the skin".
* In the weeks after injury, pain persists and a blackened crust (eschar
Eschar (; ; ; or ''an'' eschar) is a slough or piece of necrosis, dead tissue that is cast off from the surface of the skin, particularly after a Burn, burn injury, but also seen in gangrene, Ulcer (dermatology), ulcer, mycosis, fungal infection ...
) develops.
* There can be longterm ulcer
An ulcer is a discontinuity or break in a bodily membrane that impedes normal function of the affected organ. According to Robbins's pathology, "ulcer is the breach of the continuity of skin, epithelium or mucous membrane caused by sloughin ...
ation and damage to growth plates.
Fourth degree
* In fourth degree frostbite, structures below the skin are involved like muscles, tendon, and bone.
* Early symptoms include a colorless appearance of the skin, a hard texture, and painless rewarming.
* Later, the skin becomes black and mummified
A mummy is a dead human or an animal whose soft tissues and organs have been preserved by either intentional or accidental exposure to chemicals, extreme cold, very low humidity, or lack of air, so that the recovered body does not decay furthe ...
. The amount of permanent damage can take one month or more to determine. Autoamputation can occur after two months.
Causes
Risk factors
The major risk factor for frostbite is exposure to cold through geography, occupation and/or recreation. Inadequate clothing and shelter are major risk factors. Frostbite is more likely when the body's ability to produce or retain heat is impaired. Physical, behavioral, and environmental factors can all contribute to the development of frostbite. Immobility and physical stress (such as malnutrition or dehydration) are also risk factors. Disorders and substances that impair circulation contribute, including diabetes
Diabetes mellitus, commonly known as diabetes, is a group of common endocrine diseases characterized by sustained high blood sugar levels. Diabetes is due to either the pancreas not producing enough of the hormone insulin, or the cells of th ...
, Raynaud's phenomenon
Raynaud syndrome, also known as Raynaud's phenomenon, is a medical condition in which the spasm of small arteries causes episodes of reduced blood flow to end arterioles. Typically the fingers, and, less commonly, the toes, are involved. Rare ...
, tobacco
Tobacco is the common name of several plants in the genus '' Nicotiana'' of the family Solanaceae, and the general term for any product prepared from the cured leaves of these plants. More than 70 species of tobacco are known, but the ...
and alcohol
Alcohol may refer to:
Common uses
* Alcohol (chemistry), a class of compounds
* Ethanol, one of several alcohols, commonly known as alcohol in everyday life
** Alcohol (drug), intoxicant found in alcoholic beverages
** Alcoholic beverage, an alco ...
use. Homeless individuals and individuals with some mental illnesses may be at higher risk.
Mechanism
Freezing
In frostbite, cooling of the body causes narrowing of the blood vessels (vasoconstriction
Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of vasodilation, the widening of blood vesse ...
). Prolonged exposure to temperatures below may cause ice crystals to form in the tissues, and prolonged exposure to temperatures below may cause ice crystals to form in the blood. Ice crystals can damage small blood vessels at the site of injury. Typically, prolonged exposure to temperatures below may cause frostbite.
Rewarming
Rewarming causes tissue damage through reperfusion injury
Reperfusion injury, sometimes called ischemia-reperfusion injury (IRI) or reoxygenation injury, is the tissue damage caused when blood supply returns to tissue ('' re-'' + ''perfusion'') after a period of ischemia or lack of oxygen (anoxia or hy ...
, which involves vasodilation
Vasodilation, also known as vasorelaxation, is the widening of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls, in particular in the large veins, large arteries, and smaller arterioles. Blood vessel wa ...
, swelling (edema), and poor blood flow (stasis). Platelet aggregation
Platelets or thrombocytes () are a part of blood whose function (along with the coagulation factors) is to react to bleeding from blood vessel injury by clumping to form a blood clot. Platelets have no cell nucleus; they are fragments of cytop ...
is another possible mechanism of injury. Blisters and spasm of blood vessels (vasospasm
Vasospasm refers to a condition in which an arterial spasm leads to vasoconstriction. This can lead to tissue ischemia (insufficient blood flow) and tissue death (necrosis).
Along with physical resistance, vasospasm is a main cause of ischemi ...
) can develop after rewarming.
Non-freezing cold injury
The process of frostbite differs from the process of Non-freezing cold injury
Non-freezing cold injuries (NFCI) is a class of tissue damage caused by sustained exposure to low temperature without actual freezing. There are several forms of NFCI, and the common names may refer to the circumstances in which they commonly occ ...
(NFCI). In NFCI, temperature in the tissue decreases gradually. This slower temperature decrease allows the body to try to compensate through alternating cycles of closing and opening blood vessels (vasoconstriction
Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of vasodilation, the widening of blood vesse ...
and vasodilation
Vasodilation, also known as vasorelaxation, is the widening of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls, in particular in the large veins, large arteries, and smaller arterioles. Blood vessel wa ...
). If this process continues, inflammatory mast cell
A mast cell (also known as a mastocyte or a labrocyte) is a resident cell of connective tissue that contains many granules rich in histamine and heparin. Specifically, it is a type of granulocyte derived from the myeloid stem cell that is a p ...
s act in the area. Small clots (microthrombi) form and can cut off blood to the affected area (known as ischemia
Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems ...
) and damage nerve fibers. Rewarming causes a series of inflammatory chemicals such as prostaglandin
Prostaglandins (PG) are a group of physiology, physiologically active lipid compounds called eicosanoids that have diverse hormone-like effects in animals. Prostaglandins have been found in almost every Tissue (biology), tissue in humans and ot ...
s to increase localized clotting.
Pathophysiology
The pathological mechanism by which frostbite causes body tissue injury can be characterized by four stages: Prefreeze, freeze-thaw, vascular stasis, and the late ischemic stage.
# Prefreeze phase: involves the cooling of tissues without ice crystal formation.
# Freeze-thaw phase: ice-crystals form, resulting in cellular damage and death.
# Vascular stasis phase: marked by blood coagulation
Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a thrombus, blood clot. It results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The process of co ...
or the leaking of blood out of the vessels.
# Late ischemic phase: characterized by inflammatory events, ischemia
Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems ...
and tissue death.
Diagnosis
Frostbite is diagnosed based on signs and symptoms as described above, and by patient history
The medical history, case history, or anamnesis (from Greek: ἀνά, ''aná'', "open", and μνήσις, ''mnesis'', "memory") of a patient is a set of information the physicians collect over medical interviews. It involves the patient, and even ...
. Other conditions that can have a similar appearance or occur at the same time include:
* Frostnip is similar to frostbite, but without ice crystal formation in the skin. Whitening of the skin and numbness reverse quickly after rewarming.
* Trench foot
Trench foot, also known by #Names, other names, is a type of immersion foot syndromes, foot damage due to moisture. Initial symptoms often include tingling or itching which can progress to numbness. The feet may become erythema, red or cyanosis, ...
is damage to nerves and blood vessels that results from exposure to cold wet (non-freezing) conditions. This is reversible if treated early.
* Pernio or chilblains are inflammation of the skin from exposure to wet, cold (non-freezing) conditions. They can appear as various types of ulcers and blisters.
* Bullous pemphigoid
Bullous pemphigoid (a type of pemphigoid) is an autoimmune pruritic skin disease that typically occurs in people aged over 60, that may involve the formation of blisters ( bullae) in the space between the epidermal and dermal skin layers. It is ...
is a condition that causes itchy blisters over the body that can mimic frostbite. It does not require exposure to cold to develop.
* Levamisole toxicity is a vasculitis
Vasculitis is a group of disorders that destroy blood vessels by inflammation. Both artery, arteries and veins are affected. Lymphangitis (inflammation of lymphatic vessels) is sometimes considered a type of vasculitis. Vasculitis is primarily c ...
that can appear similar to frostbite. It is caused by contamination of cocaine by levamisole
Levamisole, sold under the brand name Ergamisol among others, is a medication used to treat parasitic worm infections, specifically ascariasis and hookworm infections. It is taken by mouth.
Side effects may include abdominal pain, vomiting, ...
. Skin lesions can look similar those of frostbite, but do not require cold exposure to occur.
People who have hypothermia
Hypothermia is defined as a body core temperature below in humans. Symptoms depend on the temperature. In mild hypothermia, there is shivering and mental confusion. In moderate hypothermia, shivering stops and confusion increases. In severe ...
often have frostbite as well. Since hypothermia is life-threatening this should be treated first. Technetium-99
Technetium-99 (99Tc) is an isotope of technetium that decays with a half-life of 211,000 years to stable ruthenium-99, emitting beta particles, but no gamma rays. It is the most significant long-lived fission product of uranium fission, produci ...
or MR scans are not required for diagnosis, but might be useful for prognostic purposes.
Prevention
The Wilderness Medical Society recommends covering the skin and scalp, taking in adequate nutrition, avoiding constrictive footwear and clothing, and remaining active without causing exhaustion. Supplemental oxygen might also be of use at high elevations. Repeated exposure to cold water makes people more susceptible to frostbite. Additional measures to prevent frostbite include:
* Avoiding temperatures below −23 °C (-9 °F)
* Avoiding moisture, including in the form of sweat
Perspiration, also known as sweat, is the fluid secreted by sweat glands in the skin of mammals.
Two types of sweat glands can be found in humans: eccrine glands and Apocrine sweat gland, apocrine glands. The eccrine sweat glands are distribu ...
and/or skin emollients
A moisturizer, or emollient, is a cosmetic preparation used for protecting, moisturizing, and lubricating the skin. These functions are normally performed by sebum produced by healthy skin. The word "emollient" is derived from the Latin verb ''mo ...
* Avoiding alcohol and drugs that impair circulation or natural protective responses
* Layering clothing
* Using chemical or electric warming devices
* Recognizing early signs of frostnip and frostbite
Treatment
Individuals with frostbite or potential frostbite should go to a protected environment and get warm fluids. If there is no risk of re-freezing, the extremity can be exposed and warmed in the underarm of a companion or the groin. If the area is allowed to refreeze, there can be worse tissue damage. If the area cannot be reliably kept warm, the person should be brought to a medical facility without rewarming the area. Rubbing the affected area can also increase tissue damage. Aspirin
Aspirin () is the genericized trademark for acetylsalicylic acid (ASA), a nonsteroidal anti-inflammatory drug (NSAID) used to reduce pain, fever, and inflammation, and as an antithrombotic. Specific inflammatory conditions that aspirin is ...
and ibuprofen
Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that is used to relieve pain, fever, and inflammation. This includes dysmenorrhea, painful menstrual periods, migraines, and rheumatoid arthritis. It can be taken oral administration, ...
can be given in the field to prevent clotting and inflammation. Ibuprofen is often preferred to aspirin because aspirin may block a subset of prostaglandins
Prostaglandins (PG) are a group of physiologically active lipid compounds called eicosanoids that have diverse hormone-like effects in animals. Prostaglandins have been found in almost every tissue in humans and other animals. They are derive ...
that are important in injury repair.
The first priority in people with frostbite should be to assess for hypothermia
Hypothermia is defined as a body core temperature below in humans. Symptoms depend on the temperature. In mild hypothermia, there is shivering and mental confusion. In moderate hypothermia, shivering stops and confusion increases. In severe ...
and other life-threatening complications of cold exposure. Before treating frostbite, the core temperature
Normal human body temperature (normothermia, euthermia) is the typical temperature range found in humans. The normal human body temperature range is typically stated as .
Human body temperature varies. It depends on sex, age, time of day, exert ...
should be raised above 35 °C. Oral or intravenous (IV) fluids should be given.
Other considerations for standard hospital management include:
* wound care
The history of wound care spans from prehistory to modern medicine. Wounds naturally Wound healing, heal by themselves, but hunter-gatherers would have noticed several factors and certain herbalism, herbal remedies would speed up or assist the pro ...
: blister
A blister is a small pocket of body fluid (lymph, serum, plasma, blood, or pus) within the upper layers of the skin, usually caused by forceful rubbing (friction), burning, freezing, chemical exposure or infection. Most blisters are filled ...
s can be drained by needle aspiration, unless they are bloody (hemorrhagic
Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, va ...
). Aloe vera
''Aloe vera'' () is a succulent plant species of the genus ''Aloe''. It is widely distributed, and is considered an invasive species in many world regions.
An evergreen perennial plant, perennial, it originates from the Arabian Peninsula, but ...
gel can be applied before breathable, protective dressings or bandages are put on.
* antibiotics
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting pathogenic bacteria, bacterial infections, and antibiotic medications are widely used in the therapy ...
: if there is trauma, skin infection (cellulitis
Cellulitis is usually a bacterial infection involving the inner layers of the skin. It specifically affects the dermis and subcutaneous fat. Signs and symptoms include an area of redness which increases in size over a few days. The borders of ...
) or severe injury
* tetanus toxoid
Tetanus vaccine, also known as tetanus toxoid (TT), is a toxoid vaccine used to prevent tetanus. During childhood, five doses are recommended, with a sixth given during adolescence.
After three doses, almost everyone is initially immune, but ...
: should be administered according to local guidelines. Uncomplicated frostbite wounds are not known to encourage tetanus.
* pain control: NSAIDs or opioid
Opioids are a class of Drug, drugs that derive from, or mimic, natural substances found in the Papaver somniferum, opium poppy plant. Opioids work on opioid receptors in the brain and other organs to produce a variety of morphine-like effects, ...
s are recommended during the painful rewarming process.
Rewarming
If the area is still partially or fully frozen, it should be rewarmed in the hospital with a warm bath with povidone iodine
Povidone-iodine (PVP-I), also known as iodopovidone, is an antiseptic used for skin disinfection before and after surgery. It may be used both to disinfect the hands of healthcare providers and the skin of the person they are caring for. It may ...
or chlorhexidine
Chlorhexidine is a disinfectant and antiseptic which is used for skin disinfection before surgery and to disinfect surgical instruments. It is also used for cleaning wounds, preventing dental plaque, treating yeast infections of the mouth, and ...
antiseptic
An antiseptic ( and ) is an antimicrobial substance or compound that is applied to living tissue to reduce the possibility of sepsis, infection, or putrefaction. Antiseptics are generally distinguished from ''antibiotics'' by the latter's abil ...
. Active rewarming seeks to warm the injured tissue as quickly as possible without burning. The faster tissue is thawed, the less tissue damage occurs. According to Handford and colleagues, "The Wilderness Medical Society and State of Alaska Cold Injury Guidelines recommend a temperature of 37–39 °C, which decreases the pain experienced by the patient whilst only slightly slowing rewarming time." Warming takes 15 minutes to 1 hour. The faucet should be left running so the water can circulate. Rewarming can be very painful, so pain management is important.
Medications
People with potential for large amputations and who present within 24 hours of injury can be given TPA with heparin
Heparin, also known as unfractionated heparin (UFH), is a medication and naturally occurring glycosaminoglycan. Heparin is a blood anticoagulant that increases the activity of antithrombin. It is used in the treatment of myocardial infarction, ...
.[ These medications should be withheld if there are any contraindications. Bone scans or ]CT angiography
Computed tomography angiography (also called CT angiography or CTA) is a computed tomography technique used for angiography—the visualization of arteries and veins—throughout the human body. Using contrast injected into the blood vessels, im ...
can be done to assess damage.
Blood vessel dilating medications such as iloprost
Iloprost, sold under the brand name Ventavis among others, is a medication used to treat pulmonary arterial hypertension (PAH), scleroderma, Raynaud's phenomenon, frostbite, and other conditions in which the blood vessels are constricted and b ...
may prevent blood vessel blockage. This treatment might be appropriate in grades 2–4 frostbite, when people get treatment within 48 hours. In addition to vasodilators, sympatholytic
A sympatholytic (sympathoplegic) drug is a medication that opposes the downstream effects of postganglionic nerve firing in effector organs innervated by the sympathetic nervous system (SNS). They are indicated for various functions; for example, t ...
drugs can be used to counteract the detrimental peripheral vasoconstriction
Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of vasodilation, the widening of blood vesse ...
that occurs during frostbite.
A systematic review and metaanalysis revealed that iloprost alone or iloprost plus recombinant tissue plasminogen activator (rtPA) may decrease amputation rate in case of severe frostbite in comparison to buflomedil alone with no major adverse events reported from iloprost or iloprost plus rtPA in the included studies.
Surgery
Various types of surgery might be indicated in frostbite injury, depending on the type and extent of damage. Debridement
Debridement is the medical removal of dead, damaged, or infected tissue to improve the healing potential of the remaining healthy tissue. Removal may be surgical, mechanical, chemical, autolytic (self-digestion), or by maggot therapy.
In ...
or amputation of necrotic
Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. The term "necrosis" came about in the mid-19th century and is commonly attributed to German pathologist Rudolf Virchow, who is ...
tissue is usually delayed unless there is gangrene
Gangrene is a type of tissue death caused by a lack of blood supply. Symptoms may include a change in skin color to red or black, numbness, swelling, pain, skin breakdown, and coolness. The feet and hands are most commonly affected. If the ga ...
or systemic infection (sepsis
Sepsis is a potentially life-threatening condition that arises when the body's response to infection causes injury to its own tissues and organs.
This initial stage of sepsis is followed by suppression of the immune system. Common signs and s ...
). This has led to the adage "Frozen in January, amputate in July". If symptoms of compartment syndrome
Compartment syndrome is a serious medical condition in which increased pressure within a Fascial compartment, body compartment compromises blood flow and tissue function, potentially leading to permanent damage if not promptly treated. There are ...
develop, fasciotomy
Fasciotomy or fasciectomy is a surgical procedure where the fascia is cut to relieve tension or pressure in order to treat the resulting loss of circulatory system, circulation to an area of biological tissue, tissue or muscle. Fasciotomy is a li ...
can be done to attempt to preserve blood flow.
Prognosis
Tissue loss and autoamputation are potential consequences of frostbite. Permanent nerve damage including loss of feeling can occur. It can take several weeks to know what parts of the tissue will survive. Time of exposure to cold is more predictive of lasting injury than temperature the individual was exposed to. The classification system of grades, based on the tissue response to initial rewarming and other factors is designed to predict degree of longterm recovery.
Grades
Grade 1: if there is no initial lesion on the area, no amputation or lasting effects are expected
Grade 2: if there is a lesion on the distal body part, tissue and fingernails can be destroyed
Grade 3: if there is a lesion on the intermediate or near body part, auto-amputation and loss of function can occur
Grade 4: if there is a lesion very near the body (such as the carpals of the hand), the limb can be lost. Sepsis and/or other systemic problems are expected.
A number of long term sequelae can occur after frostbite. These include transient or permanent changes in sensation, paresthesia
Paresthesia is a sensation of the skin that may feel like numbness (''hypoesthesia''), tingling, pricking, chilling, or burning. It can be temporary or Chronic condition, chronic and has many possible underlying causes. Paresthesia is usually p ...
, increased sweating, cancers, and bone destruction/arthritis
Arthritis is a general medical term used to describe a disorder that affects joints. Symptoms generally include joint pain and stiffness. Other symptoms may include redness, warmth, Joint effusion, swelling, and decreased range of motion of ...
in the area affected.
Epidemiology
There is a lack of comprehensive statistics about the epidemiology
Epidemiology is the study and analysis of the distribution (who, when, and where), patterns and Risk factor (epidemiology), determinants of health and disease conditions in a defined population, and application of this knowledge to prevent dise ...
of frostbite. In the United States, frostbite is more common in northern states. In Finland, annual incidence was 2.5 per 100,000 among civilians, compared with 3.2 per 100,000 in Montreal. Research suggests that men aged 30–49 are at highest risk, possibly due to occupational or recreational exposures to cold.
History
Frostbite has been described in military history for millennia. The Greeks encountered and discussed the problem of frostbite as early as 400 BC. Researchers have found evidence of frostbite in humans dating back 5,000 years, in an Andean mummy. Napoleon's Army was the first documented instance of mass cold injury in the early 1800s. According to Zafren, nearly 1 million combatants fell victim to frostbite in the First and Second World Wars, and the Korean War.
Society and culture
Several notable cases of frostbite include:
* Captain Lawrence Oates, an English army captain and Antarctic
The Antarctic (, ; commonly ) is the polar regions of Earth, polar region of Earth that surrounds the South Pole, lying within the Antarctic Circle. It is antipodes, diametrically opposite of the Arctic region around the North Pole.
The Antar ...
explorer who in 1912 died of complications of frostbite
* Harold Bride
Harold Sydney Bride (11 January 1890 – 29 April 1956) was a British merchant seaman and the junior wireless operator on the ocean liner during her ill-fated maiden voyage.
After the ''Titanic'' struck an iceberg at 11:40 pm 14 April 1912, B ...
, the junior wireless operator of , who suffered severe frostbite on his feet as he and other survivors stood for over an hour on the back of a capsized lifeboat knee-deep in freezing water—Bride had to be carried off from the rescue vessel after it arrived in New York
* Noted American rock climber Hugh Herr
Hugh Herr (born October 25, 1964) is an American rock climber, engineer, and biophysicist. When he was young, both of his legs were amputated below the knee due to an accident during an unexpected blizzard that occurred on a rock climbing trip. ...
, who in 1982 lost both legs below the knee to frostbite after being stranded on Mount Washington (New Hampshire)
Mount Washington is an ultra-prominent peak, ultra-prominent mountain in the state of New Hampshire. It is the highest peak in the Northeastern United States at and the most Topographic prominence, topographically prominent mountain east of the ...
in a blizzard
* Beck Weathers
Seaborn Beck Weathers (born December 16, 1946) is an American pathologist from Texas who survived the 1996 Mount Everest disaster. His story was covered in Jon Krakauer's book ''Into Thin Air'' (1997), its film adaptation '' Into Thin Air: Death ...
, a survivor of the 1996 Mount Everest disaster
The 1996 Mount Everest disaster occurred on 10–11 May 1996 when eight climbers caught in a blizzard died on Mount Everest while attempting to descend from the summit. Over the entire season, 12 people died trying to reach the summit, making i ...
who lost his nose and hands to frostbite
* Scottish mountaineer Jamie Andrew, who in 1999 had all four limbs amputated due to sepsis from frostbite sustained after becoming trapped for four nights whilst climbing Les Droites
Les Droites () is a mountain in the Mont Blanc massif in the French Alps and is the lowest of the 4000-metre peaks in the Alps. The mountain has two summits:
* West summit (3,984 m), first ascent by W. A. B. Coolidge, Christian Almer and Ulri ...
in the Mont Blanc massif
Research directions
Evidence is insufficient to determine whether or not hyperbaric oxygen therapy
Hyperbaric medicine is medical treatment in which an increase in barometric pressure of typically air or oxygen is used. The immediate effects include reducing the size of gas emboli and raising the partial pressures of the gases present. Initial ...
as an adjunctive treatment can assist in tissue salvage. Cases have been reported, but no randomized control trial
A randomized controlled trial (or randomized control trial; RCT) is a form of scientific experiment used to control factors not under direct experimental control. Examples of RCTs are clinical trials that compare the effects of drugs, surgical t ...
has been performed on humans.
Medical sympathectomy
A sympathectomy is an irreversible procedure during which at least one sympathetic ganglion is removed. One example is the lumbar sympathectomy, which is advised for occlusive arterial disease in which L2 and L3 ganglia along with intervening sy ...
using intravenous reserpine
Reserpine is a drug that is used for the treatment of hypertension, high blood pressure, usually in combination with a thiazide diuretic or vasodilator. Large clinical trials have shown that combined treatment with reserpine plus a thiazide diur ...
has also been attempted with limited success. Studies have suggested that administration of tissue plasminogen activator
Tissue-type plasminogen activator, short name tPA, is a protein that facilitates the breakdown of blood clots. It acts as an enzyme to convert plasminogen into its active form plasmin, the major enzyme responsible for clot breakdown. It is a s ...
(tPa) either intravenously or intra-arterially may decrease the likelihood of eventual need for amputation.
References
External links
Mayo Clinic
Definition
{{Authority control
Mountaineering and health
Skin conditions resulting from physical factors
Thermal medicine
Weather and health
Causes of amputation
Wikipedia medicine articles ready to translate
Wilderness medical emergencies