LOCAL EFFECTS. — In burns of the first degree the appearances produced are superficial. There will be observed a dis tinct hyperaemia with redness of varying intensity from the slightest blush up to a pinkish red or brownish red. This may or may not be entirely effaced by pressure. Persons of fair complexion or thin, delicate skin are affected more greatly by the same amount of heat than will be those of darker hue or more dense integument. Swelling is present to a slight degree and does not extend far beyond the limits actually exposed to the burning substance. This type of burn is produced by indirect contact with the flame of a lighted match, prox imity to a heated metal, escaping steam, and the actinic rays of the sun.
With or without treatment the effect of burning to this extent may disappear shortly after removing the exciting cause. Resolution takes place in this variety by the disappearance of the swelling, the serous infiltration being absorbed, the color diminishing to the normal except in those cases in which a slight degree of pigmentation is left in the form of ordinary increase, which usually disappears as time progresses or where the sun's rays cause perhaps a per manent stain such as lentiginous patches. The linear fissures of the skin appear prominent because of the semidetach ment of the membrane between them. which, as time passes, the new skin form ing beneath compels their complete de tachment in the form of minute flakes of deadened epithelium.
In burns of the second degree the in flammation, while yet superficial, may still occupy the entire epidermis. In some cases the upper layers alone of the cuticle may be destroyed, while vesicles or bulla may be observed over the af fected surface. In still other cases the corium is stripped entirely of its epi dermal covering or particles of the mem brane may be rolled into whitish masses over its exposed surface. These vesicles or bulla may be produced directly by the contact of the heated article or indirectly by the consequent inflammation. They
may retain their contents or, owing to the increased flow of serum, their walls, becoming thin and losing their elasticity, rupture, thus allowing the escape of a continual discharge over the denuded surface. The true skin, which is ex posed either entirely or at points, shows a highly-reddened surface, over which this continual exudation may be ob served. The papillary vessels are seen to be deeply congested, or, if ruptured, their flow of blood intermingles with the discharge of serum and gives it a tint of red. Swelling is present in both of these conditions, but is governed by the extent of surface and the density of the part involved. In this type of condition actual contact with the heated substance takes place either in shorter or longer durations. Such articles as heated iron, transient or lengthened action of flames, and boiling liquids may be the exciting agent. The effects of this form of burn do not always show to what extent they have progressed immediately upon the removal of the cause, because of the sys temic conditions which may be induced. Pain is always present to a minor or ma jor degree.
Resolution takes place through co agulation of the serous discharge, which occupies the involved area as a fibro albuminous covering, beneath which the new skin is allowed to form. After the new integument has progressed almost to its normal aspect this covering, which by this time has become a darkish crust, becomes loosened and falls off, exposing a thin, delicate skin, through which the more vascular structures immediately beneath are observed. It is not for weeks, months, or even years that the normal pinkish-red tint of the skin is restored. Burns of this character usu ally leave a fairly-normal aspect to the surface and rarely cause the formation of cicatrices. If a cicatrix is formed, it is generally superficial and flattened, resembling, to a marked degree, the fiat, sebaceous warts observed in the aged.