Burns are injuries to tissues caused by heat, friction, electricity, radiation, or chemicals. They may be caused by even a brief encounter with heat greater than 120°F (49°C). The source of this heat may be the sun (causinga sunburn), hot liquids, steam, fire, electricity, friction (causing rug burns and rope burns), and chemicals (causing a caustic burn upon contact).
Burns are characterized by degree, based on the severity of tissue damage. Afirst-degree burn causes redness and swelling in the outermost layers of skin(epidermis). A second-degree burn involves redness, swelling and blistering,and the damage may extend beneath the epidermis to deeper layers of skin (dermis). A third-degree burn, also called a full-thickness burn, destroys the entire depth of skin, causing significant scarring. Damage also may extend tothe underlying fat, muscle, or bone. The severity of a burn is also judged bythe amount of body surface area (BSA) it involves.
Critical, or major, burns are the most serious and should be treated in a specialized burn unit of a hospital. These are defined as first- or second-degree burns covering more than 25% of an adult's body or more than 20% of a child's body, or a third-degree burn on more than 10% BSA.
Signs of a burn are localized redness, swelling, and pain. A severe burn willalso blister. The skin may also peel, appear white or charred, and feel numb. A burn may trigger a headache and fever. Extensive burns may induce shock,the symptoms of which are faintness, weakness, rapid pulse and breathing, pale and clammy skin, and bluish lips and fingernails.
First- or second-degree burns (those covering less than 15% of an adult's body or less than 10% of a child's body, or a third-degree burn on less than 2%BSA) are considered minor burns and may be treated at home or in a doctor's office. The first act of thermal burn treatment is to stop the burning processby letting cool (not cold) water run over the burned area or by soaking it in cool water.
The burn should be cleaned gently with soap and water. Blisters should not bebroken. Butter, shortening, or salve should never be applied to the burn since it prevents heat from escaping and drives the burning process deeper intothe skin. If the skin of the burned area is unbroken, the burn should be leftexposed to the air to promote healing. If the skin is broken, the burned area should be coated lightly with an antibacterial ointment and covered with asterile bandage. The burn should also be bandaged if it is on an area where it might be disturbed, such as the sole of the foot or palm of the hand. Coolwet compresses may provide some pain relief when applied to small areas of first- and second-degree burns. Ice should never be applied to the burn.
Aspirin, acetaminophen (Tylenol), or ibuprofen (Advil) may be taken to ease pain and relieve inflammation. In addition, several homeopathic remedies, including Cantharis and Causticum, can assist in burn healing. A number of botanical remedies, applied to the skin, can also help burns heal. These include aloe (Aloe barbadensis), oil of St.-John's-wort (Hypericum perforatum), calendula (Calendula officinalis), comfrey (Symphytum officinale), and tea tree oil (Melaleuca spp.).
A doctor should be consulted if any signs of infection appear while the burnis healing, including: increased warmth, redness, pain, or swelling; pus or similar drainage from the wound; swollen lymph nodes; or red streaks spreadingaway from the burn. Minor burns typically heal in 5-10 days with no scarring.
In situations where a person has received moderate or critical burns, lifesaving measures take precedence over burn treatment and emergency medical assistance must be called. Severe burns may cause the victim to stop breathing, andartificial respiration (also called mouth-to-mouth resuscitation or rescue breathing) should be administered immediately. Also, a person with burns covering more than 12% BSA is likely to go into shock; this condition may be prevented by laying the person flat and elevating the feet about 12 in (30 cm). Burned arms and hands should also be raised higher than the person's heart.
In the case of burns from fire, clothes that are smoldering or smoking shouldbe removed. However, any clothing that is embedded in the burn should not bedisturbed. Covering the burn victim with a light, cool, wet cloth, such as asheet but not a blanket or towel, will stop the burning process.
Burns from liquid chemicals must be rinsed with cool water for at least 15 minutes to stop the burning process. In cases of burns from dry chemicals suchas lime, the powder should be completely brushed away before the area is washed. Any clothing which may have absorbed the chemical should be removed. Theburn should then be loosely covered with a sterile gauze pad and the person taken to the hospital for further treatment. A physician may be able to neutralize the offending chemical with another before treating the burn like a thermal burn of similar severity.
Before electrical burns are treated at the site of the accident, the power source must be disconnected if possible and the victim moved away from it to keep the person giving aid from being electrocuted. Electrical burns should beloosely covered with sterile gauze pads and the person taken to the hospitalfor further treatment.
At the hospital, the staff will provide further medical treatment. A tube toaid breathing may be inserted if the patient's airways or lungs have been damaged. Also, because burns dramatically deplete the body of fluids, replacement fluids are administered intravenously. The patient is also given antibiotics intravenously to prevent infection, and he or she may also receive a tetanus shot.
Once the burned area is cleaned and treated with antibiotic cream or ointment, it is covered in sterile bandages, which are changed 2-3 times a day. Surgical removal of dead tissue (debridement) also takes place. The burn victim may also be placed in a hyperbaric chamber. In a hyperbaric chamber (which canbe a specialized room or enclosed space), the patient is exposed to pure oxygen under high pressure, which can aid in healing if administered in the first24 hours after the burn injury occurs.
Moderate burns usually heal in 10-14 days and may leave scarring. Critical ormajor burns take longer to heal, and leave significant scarring. As the burns heal, thick, taut scabs (eschar) form, which the doctor may have to cut toimprove blood flow to the more elastic healthy tissue beneath. The patient will also undergo physical and occupational therapy to keep the burned areas from becoming inflexible. In cases where the skin has been so damaged that it cannot properly heal, a skin graft is usually performed. A skin graft involvestaking a piece of skin from an unburned portion of the patient's body (autograft) and transplanting it to the burned area. When doctors cannot immediately use the patient's own skin, a temporary graft is performed using the skin of a human donor (allograft), either alive or dead, or the skin of an animal (xenograft), usually that of a pig.