THE CLASSIFICATION OF BURNS.
A classification of burns according to the severity of the injury inflicted is the most practical course. Upon this plan, burns may be divided into four general classes:
I. Burns in which the skin or subcutaneous cellular tissues only are injured.
II. Burns which involve the muscles, nerves, and blood-vessels.
III. Burns involving the internal organs and bones.
IV. Burns in which the other three classes are variously mixed.
Class I.—The skin in cases such as may occur from a brief contact with a hot body or water near the boiling-point shows a slight redness or scorching with no enduring mark. Pain is considerable.
Class II.—In the mildest cases the cutis is destroyed in its whole thickness, and the parts injured are occupied by eschars of a yellowish-gray or brownish color. The surrounding skin is reddened, and the formation of blisters occurs either immediately or after an interval of a few hours. In these cases a shining cicatrix remains after the healing, without contraction of surrounding parts. In the severer cases the subcutaneous cellular tissue and underlying muscles and nerves are destroyed. The blackish eschars formed are insensible and separate by suppurative process, leaving a granulating surface below. Extensive redness of surrounding tissues, with more or less vesication, is usually noted. The resulting cicatrices, together with the skin and adjoining structures, are prone to contraction, resulting in considerable deformity, according to location and extent. So great is the deformity in injuries of the extremities, or even some parts of the head and trunk, that extensive surgical operations become necessary to relieve it.
Class III.—Burns of this class are so severe that an immediately fatal issue is usually the result. Such instances involve a prolonged exposure to flame or to a source of intense heat. The appearances described as belonging to the preceding class are in part found here with the addition of charring or carbonizing the parts destroyed.