Frostbite is a local tissue damage that develops when exposed to cold. Frostbite has a latent and reactive period coming after warming up. Pathology is manifested by discoloration, pain, sensitivity disorders, the appearance of blisters and foci of necrosis. Damage of the III and IV degrees leads to the development of gangrene and spontaneous rejection of the fingers. Treatment is carried out with vascular drugs (pentoxifylline, nicotinic acid, antispasmodics), antibiotics, physiotherapy; relief of pain syndrome is carried out by novocaine blockades.
ICD 10
T33-T35 Frostbite
Frostbite causes
The cause of tissue damage can be frost, direct contact with an object cooled to an ultra-low temperature (contact frostbite) and prolonged periodic cooling in conditions of high humidity (“trench foot”, chills). Factors contributing to the development of frostbite are strong wind, high humidity, decreased local and general immunity (as a result of illness, injury, vitamin deficiency, malnutrition, etc.), alcohol intoxication, tight clothing and shoes that cause circulatory disorders.
Pathogenesis
Exposure to low temperatures causes persistent vascular spasm. Blood flow rate decreases, blood viscosity increases. Shaped elements “clog” small vessels, blood clots form. Thus, pathological changes in frostbite occur not only as a result of direct exposure to cold, but also as a result of a reaction from the vessels. Local circulatory disorders provoke disturbances on the part of the autonomic nervous system, which regulates the activity of all internal organs. As a result, inflammatory changes develop in organs removed from the place of frostbite (respiratory tract, bones, peripheral nerves and gastrointestinal tract).
Frostbite symptoms
Clinical manifestations are determined by the degree and period of the lesion. The latent (pre-reactive) period of frostbite develops in the first hours after injury and is accompanied by scant clinical symptoms. Minor pain, tingling, sensitivity disorders are possible. The skin in the area of frostbite is cold, pale.
After warming the tissues, a reactive period of frostbite begins, the manifestations of which depend on the degree of tissue damage and complications caused by the underlying pathology.
There are four degrees of frostbite:
- With frostbite of the first degree, moderate edema appears in the reactive period. The affected area becomes cyanotic or acquires a marble color. The patient is concerned about burning pains, paresthesia and itching of the skin. All signs of frostbite disappear on their own within 5-7 days. Subsequently, there is often an increased sensitivity of the affected area to the action of cold.
- Frostbite of the II degree is accompanied by necrosis of the surface layers of the skin. After warming, the affected area becomes cyanotic, sharply edematous. On 1-3 days, bubbles with serous or serous-hemorrhagic contents appear in the area of frostbite. When the bubbles are opened, a painful wound is exposed, healing independently after 2-4 weeks.
- With frostbite of the III degree, necrosis spreads to all layers of the skin. In the pre-reactive period, the affected areas are cold, pale. After warming, the lesion site becomes sharply edematous, bubbles filled with hemorrhagic fluid appear on its surface. When opening the bubbles, wounds with a painless or slightly painful bottom are exposed.
- Frostbite of the IV degree is accompanied by necrosis of the skin and underlying tissues: subcutaneous tissue, bones and muscles. As a rule, areas of deep tissue damage are combined with areas of frostbite of I-III degree. Areas of frostbite of the IV degree are pale, cold, sometimes slightly edematous. There is no sensitivity.
With frostbite of the III and IV degrees, dry or wet gangrene develops. Dry gangrene is characterized by gradual drying of tissues and mummification. The area of deep frostbite turns dark blue. In the second week, a demarcation furrow forms, separating necrosis from “living” tissues.
Spontaneous finger rejection usually occurs 4-5 weeks after frostbite. With extensive frostbite with necrosis of the feet and hands, rejection begins at a later date, especially in cases where the demarcation line is located in the area of bone diaphysis. After rejection, the wound is filled with granulations and heals with the formation of a scar.
Wet gangrene during frostbite proceeds more unfavorably, accompanied by a sharp swelling of soft tissues and the formation of a large number of blisters with bloody contents. Tissue breakdown products are absorbed into the blood from the affected area and cause severe intoxication. There is a high probability of developing local (phlegmon, osteomyelitis, arthritis) and general (sepsis) infectious complications. Wet gangrene in frostbite is often complicated by anaerobic infection.
Chills occur during periodic cooling (usually at temperatures above 0) and high humidity. Dense bluish-purple swellings appear on the peripheral parts of the body (hands, feet, protruding parts of the face). The sensitivity of the affected areas decreases. The patient is concerned about itching, bursting or burning pains. Then the skin in the area of chills becomes rough and covered with cracks. When the hands are affected, physical strength decreases, the patient loses the ability to perform delicate operations. Further erosion or development of dermatitis is possible.
Chills develop with moderate, but prolonged and continuous exposure to wet cold. At first, there are sensitivity disorders in the thumb area, gradually spreading to the entire foot. The limb becomes edematous. With repeated cooling and warming, wet gangrene is possible.
Frostbite treatment
The victim should be moved to a warm room, warmed up, given tea, coffee or hot food. Areas of frostbite should not be intensively rubbed or quickly warmed. When rubbing, multiple microtraumas of the skin occur. Too rapid warming leads to the fact that the normal level of metabolic processes is restored faster than the blood supply to the affected areas. As a result, necrosis may develop in deprived tissues. The best result is achieved when warming “from the inside” – applying heat-insulating cotton-gauze bandages to the area of frostbite.
Upon admission to the department of traumatology, a patient with frostbite is warmed up. A mixture of solutions of novocaine, euphyllin and nicotinic acid is injected into the artery of the damaged limb. Prescribe drugs to restore blood circulation and improve microcirculation: pentoxifylline, antispasmodics, vitamins and ganglioblockers, with severe lesions – corticosteroids. Intravenously and intraarterially, solutions of rheopolyglucine, glucose, novocaine and salt solutions heated to 38 degrees are administered. A patient with frostbite is prescribed broad-spectrum antibiotics and anticoagulants (heparin for 5-7 days). Perform a case novocaine blockade.
To reduce the stimulation of recovery processes, reduce swelling and pain, physiotherapy (magnetotherapy, ultrasound, laser irradiation, diathermy, UHF) is performed. Bubbles are punctured without removing. Alcohol-chlorhexidine and alcohol-furaciline wet-drying bandages are applied to the frostbite area, with suppuration – bandages with antibacterial ointments. With significant edema, orthopedic traumatologists perform fasciotomy to eliminate tissue compression and improve blood supply to the frostbite area. With the preservation of pronounced edema and the formation of necrosis sites, necrectomy and necrotomy are performed on 3-6 days.
After the demarcation line is formed, the volume of surgical intervention is determined. As a rule, viable soft tissues are preserved under damaged skin in the demarcation zone, therefore, in case of dry necrosis, a wait-and-see treatment tactic is usually chosen, allowing more tissues to be preserved. With wet necrosis, there is a high probability of the development of infectious complications with the spread of the process “up” through healthy tissues, therefore, wait-and-see tactics are not applicable in such cases. Surgical treatment for frostbite of the IV degree consists in the removal of dead areas. Necrotic fingers, hands or feet are amputated.
Prognosis and prevention
With superficial frostbite, the prognosis is conditionally favorable. Limb functions are restored. In the long-term period, increased sensitivity to cold, nutritional disorders and vascular tone in the area of the lesion area persist for a long time. It is possible to develop Raynaud’s disease or obliterating endarteritis.With deep frostbite, the outcome is the amputation of a part of the limb. Prevention includes choosing clothes and shoes taking into account weather conditions, refusing to stay outside for a long time in the cold, especially when intoxicated.
