burn

an injury to the skin, mucosa, and underlying tissue as a result of exposure to high temperatures (thermal burns), such chemicals as concentrated acids and caustic bases (chemical burns), electric current (electric burns), and ionizing radiation (radiation burns). The severity of the injury is determined by the depth and extent of the burn.

In 1960, Soviet medicine adopted the classification of burns that is based on the determination of the depth of pathological changes in the tissues. According to this classification, first-degree burns are accompanied by redness and edema; second-degree, by the formation of blisters; third-degree, by dry or colliquative necrosis of the skin with liquefaction of dead tissues; and fourth-degree, by charring of the skin and the underlying tissues—fatty tissue, fascia, muscle, and bone. The area of a burn can be determined by several methods, including the use of tables, formulas, and simple measurement with the palm of the hand. (The area covered by an outstretched hand is roughly equivalent to 1–1.2 percent of the surface area of the body.) A first-degree burn is usually considered life-threatening if it covers 50 percent of the body; second-degree, more than 30 percent; and third-degree, about 30 percent. With superficial first- and second-degree burns that cover more than 20 percent of the body, burn syndrome arises. This is characterized by four stages: shock; acute toxemia, in which the body is poisoned by microbial toxins and the products of tissue breakdown; septicemia, in which suppuration arises; and convalescence, or recovery.

First aid procedures for first- and second-degree burns involve eliminating the source of the burn, warming the body and taking other measures to prevent shock, applying dry, sterile dressings (in cases of extensive burns, wrapping with a clean sheet), and transporting the victim to a hospital or clinic.

In chemical burns, the rapid reaction between acids and tissue proteins results in coagulation necrosis and formation of a solid dry crust. First aid consists of copious washing with tapwater and subsequent application of a 2-percent sodium carbonate solution. Caustic bases cause colliquative necroses that dissolve the surface layers of the skin and form a soft, loose crust. After copious washing with water, pads soaked in mild solutions of weak acids, for example, a 2-percent solution of acetic or boric acid or 0.5-percent solution of citric acid, are applied to the affected area. In burns of the esophagus and stomach caused by the ingestion of bases or vinegar essence, the victim must drink large quantities of milk or water and receive antidotes. Chemical burns of the eyes require flushing with water. In all cases, the victims must be promptly brought to a hospital or clinic.

In the hospital, tetanus antitoxin and toxoid are administered, the skin around the burn is treated with alcohol, and a dry dressing is applied. Local burns are treated by the closed method, which involves the application of dressings impregnated with antibacterial ointments; in some cases, the exposure method is used. Deep burns require an operation called dermoplasty to close the skin lesion. The general treatment involves blood transfusion, infusion of blood substitutes, infusion of serum from patients who are recovering from burns, oxygen therapy, and the use of antibiotics, antihistamines, and vitamins. The victim should be kept on a high-calorie, protein-rich diet. Aseptic procedures must be observed. The linen should be frequently changed and the patient’s room should be well ventilated. Prevention of bedsores and other complications is essential.