Most burns are caused by hot objects, explosions, or scalding. They may also be caused by electrical malfunctions, contact with harmful chemicals, or abrasion. Burns are assessed in terms of the depth of damage and the percentage of body surface area (BSA) involved. Depth of tissue destruction is categorized as follows:

•Superficial partial-thickness, which involves the epidermis and perhaps a portion of the dermis. The tissue is reddened and may blister, as in cases of sunburn.

•Deep partial-thickness, which involves the epidermis and portions of the dermis. The tissue is blistered and broken and has a weeping surface. Causes include scalding and flash flame.

•Full-thickness, which involves the full skin and sometimes subcutaneous tissue and underlying tissues as well. The tissue is broken and is dry and pale or charred. These injuries may result in loss of digits or limbs and require skin grafting.

The above classification replaces an older system of ranking burns as first-, second-, and third-degree according to the depth of tissue damage.

The amount of BSA involved in a burn may be estimated by using the rule of nines, in which areas of body surface are assigned percentages in multiples of nine (Fig. 1). The more accurate Lund and Browder method divides the body into small areas and estimates the proportion of BSA that each contributes.

Infection is a common complication of burns because a major defense against invasion of microorganisms is damaged. Respiratory complications and shock may also occur.

Treatment of burns includes respiratory care, administration of fluids, wound care, and pain control. Monitoring for cardiovascular complications, infections, and signs of posttraumatic stress are also important.

FIGURE 1. The rule of nines. Percentage of body surface area (BSA) in the adult is estimated by sectioning the body surface into areas with numerical values related to nine. (Reprinted with permission from Smeltzer SC, Bare BG. Brunner & Suddarth's Textbook of Medical-Surgical Nursing. 9th Ed. Philadelphia: Lippincott Williams & Wilkins, 2000.)

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