Frostbite

Description:

Freezing injury — the damage to fabrics caused by influence of low temperatures.

Freezing injury symptoms:

Peripheral body parts usually are exposed to freezing injuries: fingers of feet and brushes, auricles, nose. Often freezing injuries develop against the background of the general cooling of an organism.

Depending on conditions of impact of cold allocate the freezing injuries caused by a frost; the contact freezing injuries caused by direct action on skin of the cold agent with an ultralow temperature; the freezing injuries which arose under the influence of cold at air temperature close to 0 °C (perfigeration, "trench foot").

Under the influence of cold there is a resistant neuroreflex vasospasm to the expressed circulatory disturbance. Delay of a blood-groove, then стаз with the subsequent thrombosis of vessels is caused by a spasm. The circulatory disturbances developing under the influence of cold in extremities cause disturbances of a vegetative innervation which are the reason of reflex emergence of pathological changes in the bodies remote from sites of cooling.

Distinguish four degrees of freezing injury. At freezing injury of the I degree the expressed pallor of skin, decrease in sensitivity is noted. After the beginning of warming thermalgias, an itch of skin, paresthesia, moderate hypostasis, cyanosis or marble coloring of affected areas appear. These phenomena pass independently within 5 — 7 days. However further for many years hypersensitivity of affected areas by cold can remain.

At freezing injury of the II degree there is a necrosis of blankets of skin, including separate elements of a papillary layer. After the beginning of warming sharply expressed hypostasis of affected areas, their cyanosis develops, and later 1 — 3 day bubbles with transparent light yellow or pale hemorrhagic contents appear. The wound which is a bottom of such bubbles is very painful. Healing happens independently during 2 — 4 weeks.

Freezing injury of the III degree is characterized by a necrosis of all layers of skin. The struck fabrics pale, cold to the touch. After warming there is hypostasis, bubbles with hemorrhagic contents appear. Bottom of wounds without serious consequences or maloboleznenno.

Freezing injury of the IV degree represents a deep necrosis up to bones. As a rule, it is combined with freezing injuries of I, II and III degrees. In sites with freezing injuries of the IV degree sensitivity is completely lost, hypostasis is absent or small, fabrics pale, cold to the touch.

At freezing injury of III and IV degrees the clinical course of defeat is defined further by the nature of gangrene (dry or wet) and contamination of fabrics. The freezing injuries of III, IV degrees proceeding as dry gangrene are characterized by gradual mummification, drying of fabrics, dark blue coloring, education from 2nd week of a demarcation furrow. Spontaneous rejection of nekrotizirovanny fingers of brushes and feet can happen later 4 — 5 weeks.

At development of wet gangrene there is sharp hypostasis of fabrics, a large number of bubbles with hemorrhagic contents appears, the expressed intoxication caused by absorption in blood of decomposition products from a necrosis zone develops. Generalization of an infection, and also its specific forms are possible: mephitic gangrene, tetanus.

It is difficult to finalize necrosis borders in the first days, they are defined at formation of a line of demarcation. For early identification of border of freezing injury use a research of painful sensitivity (on a prick a needle) from distal departments of an extremity to proximal where the border of full anesthesia is defined if after days the border of anesthesia is in the same limits, then it corresponds to the level of future demarcation of a necrosis.

Perfigeration develops under the influence of long chronic impact of wet cold on various body parts, is more often at a temperature higher About °C.

"Trench foot" — the form of freezing injury of feet arising under the influence of moderate, but continuous and long action of wet cold. The disease begins with disorder of touch, thermal and painful sensitivity which appear at first on the internal and bottom surface of thumbs of feet, and then extend to all foot. The hypostases which are not disappearing after warming join.

First aid at freezing injury consists in transfer of the victim to the warm room, its wrapping, imposing of a heat-insulating wadded gauze bandage on an extremity. It is given tea, coffee, hot food, in 1 — 2 g of acetylsalicylic acid. Grinding of the freezed body parts snow contraindicated as leads to multiple microtraumas of skin.

At receipt in a hospital of the victim warm within 40 — 60 min. in a bathtub with weak solution of potassium permanganate, gradually increasing temperature from 18 to 38 °C. Let's allow careful massage from the periphery to the center. Excessively active warming leads to bystry recovery of exchange processes in cells that is not provided with adequate recovery of blood circulation and is the reason of an ischemic necrosis of fabrics.

Freezing injury reasons:

Refer the increased air humidity, strong wind, close footwear and clothes, alcoholic intoxication, decrease in body resistance as a result of an injury to the factors promoting freezing injury, blood losses, avitaminosis, hunger, etc.

Treatment of Freezing injury:

Treatment has to be directed mainly to endogenous warming with perhaps bystry recovery of blood circulation in the struck fabrics and microcirculation improvement. Apply ganglioblokiruyushchy, antispasmodics, vitamins, in more hard cases — corticosteroids; intravenous or intra arterial administration of the solutions of glucose, a reopoliglyukin which are warmed up to 38 °C, 0,25% of solution of novocaine, saline solutions; futlyarny novocainic blockade is shown. The patient enter antitetanic serum and tetanic anatoxin, appoint antibiotics of a broad spectrum of activity. Bubbles at the uncontaminated surface of skin puncture at the basis, impose wet drying alcohol - furacilinum, bandage alcohol-hlorgeksidinovye. At suppuration use ointments on a water-soluble basis (левосин, левомеколь, диоксиколь).

For the purpose of reduction of pains and hypostasis, activation of reparative processes appoint physiotherapeutic procedures (UVCh-therapy, a diathermy, laser radiation, ultrasound and magnetotherapy). Acceleration of mummification of a necrosis is promoted by the placement of frost-bitten body parts to local abacterial isolation centers with the managed temperature and air humidity.

The long time after freezing injury remains hypersensitivity by cold, vasculomotor and trophic disturbances which are characteristic of a cold neurovasculitis development of an obliterating endarteritis, Raynaud's disease is possible.

In prevention of freezing injuries development of resistance to cold by an organism hardening is of great importance.