Burns injure the skin layers and can also injure other parts of the body, such as muscles, blood vessels, nerves, lungs, and eyes. Burns are defined as first, second, third, or fourth degree, depending on how many layers of skin and tissue are burned. The deeper the burn and the larger the burned area, the more serious the burn is.
First-degree burns are burns of the first layer of skin. A first-degree burn is a minor red burn of the top layer of skin, such as a mild sunburn. The burned skin may hurt and be slightly swollen, and it may make a person feel slightly feverish. First-degree burns usually heal with home treatment in about 3 to 5 days. They do not usually cause blisters or scars.
There are two types of second-degree burns (partial-thickness burns), defined by their depth:
- Superficial partial-thickness burns injure the first and second layers of skin and are often caused by hot water or hot objects. The skin around the burn turns white (blanches) when pressed, then turns back to red. The burn is moist and painful with blistering and swelling that usually lasts for at least 48 hours.
- Deep partial-thickness burns injure deeper skin layers and are white with red areas. They are often caused by contact with hot oil, grease, soup, or microwaved liquids. This kind of burn is not painful, but it can cause a sensation of pressure. The skin looks spotted, remains white when pressed, may appear waxy in some areas, and is dry or slightly moist. Possible infection is an important concern with these burns.
It may take several days before symptoms develop and it becomes clear whether the burn is superficial or deep. Treatment varies for a second-degree burn depending on its size, depth, and a person’s age and overall health. With all burns, it is important to watch for and seek treatment for any signs of infection. Second-degree burns may leave scars after the burns heal.
Third-degree burns, also called full-thickness burns, injure all the layers of the skin as well as the fatty tissue beneath them. These are serious burns that can affect the skin’s ability to grow back. These burns always require medical treatment. A third-degree burn can cause severe pain. But if nerve endings are damaged, the burn may not hurt right away. Third-degree burns may look white, cherry red, or black, and they do not change color when you press on them (they do not blanch). Although blisters may develop, the burn is mostly dry, hard, and leathery-looking. Common causes of third-degree burns are steam, hot oil, grease, chemicals, electrical currents, and hot liquids. Infection is a major concern with third-degree burns. These burns always require care from a doctor. With small burns, new skin sometimes grows in from unburned areas. Large burns may require skin grafts and surgery.
Fourth-degree burns extend through the skin to injure muscle, ligaments, tendons, nerves, blood vessels, and bones. These burns always require medical treatment.
The seriousness of a burn is determined by several things, including:
- The depth, size, cause, affected body area, age, and health of the burn victim.
- Any other injuries that occurred, and the need for follow-up care.
Burns affect people of all ages, though some are at higher risk than others.
- Most burns that occur in children younger than age 5 are scald burns from hot liquids.
- Over half of all burns occur in the 18- to 64-year-old age group.
- Older adults are at a higher risk for burns, mostly scald burns from hot liquids.
- Men are twice as likely to have burn injuries as women.