Burns Health Article

Definition

Burns are injuries to tissues caused by heat, friction, electricity, radiation, or chemicals.

Description

Burns are characterized by degree, based on the severity of the tissue damage. A first-degree burn causes redness and swelling in the outermost layers of the 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 may also extend to the underlying fat, muscle, or bone.

The severity of a burn is also judged by the amount of body surface area (BSA) involved. Health care workers use the rule of nines to determine the percentage of BSA affected in persons more than nine years old: each arm with its hand is 9% of BSA; each leg with its foot is 18%; the front of the torso is 18%; the back of the torso, including the buttocks, is 18%; the head and neck are 9%; and the genital area (perineum) is 1%. This rule cannot be applied to a young child's body proportions, so BSA is estimated using the palm of the person's hand as a measure of 1% area.

The severity of a burn will determine not only the type of treatment, but also where the burned individual should receive treatment. Minor burns may be treated at home or in a doctor's office. These are defined as first- or second-degree burns that cover less than 15% of an adult's body or less than 10% of a child's body, or a third- degree burn of less than 2% BSA. Moderate burns should be treated at a hospital. These are defined as first- or second-degree burns that cover 15%–25% of an adult's body or 10%–20% of a child's body, or a third-degree burn on 2%–10% BSA. 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 that cover more than 25% of an adult's body or more than 20% of a child's body, or a third-degree burn of more than 10% BSA. In addition, burns involving the hands, feet, face, eyes, ears, or genitals are considered critical. Other factors influence the level of treatment needed, including associated injuries such as bone fractures and smoke inhalation, presence of a chronic dis- ease, or a history of being abused. Children and the elderly are more vulnerable to complications from burn injuries and require more intensive care.

Causes and symptoms

Burns 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 (causing a sunburn), hot liquids, steam, fire, electricity, friction (causing rug burns and rope burns), and chemicals (causing a caustic burn upon contact).

Signs of a burn are localized redness, swelling, and pain. A severe burn will also blister. The skin may peel, appear white or charred, and feel numb. A burn may trig- ger 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.

Diagnosis

Physicians will diagnose a burn based upon visual examination, and will also ask the burned person or family members questions that help determine the best treatment. They may also check for smoke inhalation, carbon monoxide poisoning, cyanide poisoning, other event- related trauma, or, if suspected, further evidence of child abuse.

Treatment

Burn treatment consists of relieving pain, preventing infection, and maintaining body fluids, electrolytes, and calorie intake while the body heals. Treatment of chemical or electrical burns is slightly different from the treatment of thermal burns, but the objectives are the same.