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Classification of burn injury

Phillip L Rice, Jr, MD
Dennis P Orgill, MD, PhD
Section Editor
Marc G Jeschke, MD, PhD
Deputy Editor
Kathryn A Collins, MD, PhD, FACS


Burns are commonly thought of as injury to the skin caused by excessive heat. More broadly, burns result from traumatic injuries to the skin or other tissues primarily caused by thermal or other acute exposures. Burns occur when some or all of the cells in the skin or other tissues are destroyed by heat, electrical discharge, friction, chemicals, or radiation. Burns are acute wounds caused by an isolated, non-recurring insult, and healing ideally progresses rapidly through an orderly series of steps [1].

The mechanisms that result in burns and their classification will be reviewed here. The clinical assessment and management of burns in adults and children are discussed elsewhere. (See "Treatment of minor thermal burns" and "Treatment of superficial burns requiring hospital admission" and "Overview of the management of the severely burned patient".)


Heat — The depth of the thermal injury is related to contact temperature, duration of contact of the external heat source, and the thickness of the skin. Because the thermal conductivity of skin is low, most thermal burns involve the epidermis and part of the dermis [2]. The most common thermal burns are associated with flames, hot liquids, hot solid objects, and steam.

Electrical discharge — Electrical energy is transformed into heat as the current passes through poorly conducting body tissues. Electroporation (injury to cell membranes) disrupts membrane potential and function. The magnitude of the injury depends on the pathway of the current, the resistance to the current flow through the tissues, and the strength and duration of the current flow. (See "Environmental and weapon-related electrical injuries".)

Friction — Injury from friction can occur due to a combination of mechanical disruption of tissues as well as heat generated by friction.

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Literature review current through: Nov 2017. | This topic last updated: Oct 05, 2017.
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