Medical Dermatology - Burns
Burns are a type of traumatic injury caused by thermal, electrical, chemical, or electromagnetic energy. Most burn accidents occur at home. Many others occur at work. More than two million burn injuries occur each year in the US, resulting in 100,000 to 300,000 hospitalizations.
An open flame is the leading cause of burn injury for adults, while scalding is the leading cause of burn injury for children. Both infants and the elderly are at the greatest risk for burn injury.
Types of Burns
A burn injury usually results from an energy transfer to the body. There are many types of burns caused by thermal, radiation, chemical, or electrical contact:
thermal burns - burns due to external heat sources which raise the temperature of the skin and tissues and cause tissue cell death or charring. Hot metals, scalding liquids, steam, and flames, when coming in contact with the skin, can cause thermal burns.
radiation burns - burns due to prolonged exposure to ultraviolet rays of the sun, or to other sources of radiation such as x-ray.
chemical burns - burns due to strong acids, alkalies, detergents, or solvents coming into contact with the skin and/or eyes.
electrical burns - burns from electrical current, either alternating current (AC) or direct current (DC).
Burns are classified as first-, second-, or third-degree, depending on how deep and severe they penetrate the skin's surface:
First-degree (superficial) burns
First-degree burns affect only the epidermis, or outer layer of skin. The burn site is red, painful, dry, and with no blisters. Mild sunburn is an example. Long-term tissue damage is rare and usually consists of an increase or decrease in the skin color.
Second-degree (partial thickness) burns
Second-degree burns involve the epidermis and part of the dermis layer of skin. The burn site appears red, blistered, and may be swollen and painful.
Third-degree (full thickness) burns
Third-degree burns destroy the epidermis and dermis. Third-degree burns may also damage the underlying bones, muscles, and tendons. The burn site appears white or charred. There is no sensation in the area since the nerve endings are destroyed.