BURNS AND SCALDS.
Cases of accidental burning or scalding are not common in veterinary practice. Those met with are usually the result of the spilling of hot liquids or of the use of fomentations at too high a temperature or of insufficiently cooled poultices. Dogs and cats sometimes receive burns from hot cinders; occasionally the coat of long-haired dogs has been known to ignite through too close contact with an open fire place. The burning down of stables has at times been responsible for very severe cases of burning among horses apart from many deaths. Malicious burning is not unknown, and several cases have found their way into the police courts, particularly with reference to the use of flame as a"cure"for jibbing horses. Unskilful branding sometimes produces severe injury.
All portions of the body are by no means equally susceptible to the application of heat, and fluids or solids of moderately high tempera ture, which would cause vesication of certain skin areas, produce no ill-effect in others. The ventral surface of the body, lips, and nostrils are very subject to injury by heat. Dogs frequently suffer from cracking and de squamation of the skin of the muzzle through constantly lying in close proximity to a fire-place.
Three classes of burns and scalds are recog nized in relation to their severity.
(1) Those which produce mere reddening of the skin. The condition is only one of short duration, but may be attended by considerable pain. It may be produced by overheated poul tices or fomentations, which may, however, be sufficiently severe to produce scalds of the second class, to be presently described. The reddening of the skin in most cases soon subsides, but if the heat employed has been sufficient to injure or destroy the epidermal cells, desquama tion follows.
(2) Those which are attended by vesication. The vesicles make their appearance almost im mediately in the majority of cases, though sometimes they may not become evident until several days have elapsed. They result from exudation of serum from the cutis. The con dition is an exceedingly painful one, particularly when the vesicles have burst or become torn or rubbed. Cold air causes extreme irritation of the exposed true skin, and if the affected area be of large extent so-called"shock"may result, particularly if the injury be to any portion of the trunk.
In animals, owing to the difficulty of main taining asepsis, and of controlling the animals' desire to lick or rub the parts, infection almost always occurs and leads to suppuration.
(3) Those in which the whole thickness of the skin is destroyed or rendered necrotic.
Large areas of skin and underlying tissues slough away, leaving extensive wounds which heal only after many weeks or months owing to the impaired resistance of the surrounding tissues produced by the degree of heat. Sup puration is always extensive and may be accom panied by crops of secondary abscesses in the tissues immediately surrounding the injury.
Dogs and cats occasionally suffer from this class of injury as a result of accidental spilling of boiling water from kettles, etc. A large piece of skin may then slough from the part affected, usually the back, and owing to the amount of fat usually underlying this part gangrenous changes occur with the discharge of fcetid pus and the shedding of necrotic fragments.
Shock more often follows this type of burn or scald, but is not nearly so common as in the more highly-strung human subject. The recog nized symptoms are shivering, cold extremities, feeble pulse, dyspncea, followed by coma and death, or in some instances by nervous excite ment and delirium. The most marked post mortem lesions are those of congestion of the brain and cedema of the lungs.
Treatment. Cold applications relieve the burning sensation, but to produce a lasting effect their action must be continuous. A warm
dressing, such as a paste prepared of finely powdered kaolin rubbed down with water at a temperature of about 120° F., at first increases the sensibility but after the first few minutes diminishes the pain, and it has been found that by applying subsequent dressings each at a slightly lower temperature than the last the burnt or scalded area can, after a moderate length of time, be left exposed to the air without causing pain.
As an emergency dressing to relieve the acute pain experienced immediately upon the receipt of a burn, a thick dressing of flour or starch may be applied or even the white of an egg. Carron oil when available is a well-known and useful application, and an emulsion of lime-water and milk much resembles it and is preferred by many surgeons. Soap liniment, treacle, or warm vinegar have also been recommended by various authors. A solution of chloretone in a bland oil or liquid paraffin is now much employed.
After the formation of vesicles, further treat ment will be required. If of small size and not too tense, wrapping in wool soaked in any of the above-mentioned applications may be re sorted to, but should the vesicles become con fluent and extensive or very tense, they should be pricked with a surgically-clean needle. An antiseptic dressing should then be applied such as a solution of chloretone in oil, to which a little oil of eucalyptus may be added, and the parts should be thickly padded with cotton wool and a light bandage applied over all. This dressing should not be disturbed for several days unless the wool becomes saturated with lymph or other discharge. Upon removal, if still aseptic, mild astringent lotions should be employed. Zinc sulphate gr. ii. to 3i. water answers this purpose quite well.
Cases of the third type, associated with death of the part and extensive suppuration, should be treated as open wounds. Shreds of necrotic tissue may be removed by means of curved scissors. Frequent fomentation with warm saline solution and an occasional application of tinct. iodi. give good results. After suppura tion diminishes and the parts appear more healthy they should be powdered thickly with consecutive layers of dry antiseptic dressing, such as a mixture of zinc oxid., acid boric, and starch until the whole is covered by a thick scab.
Shock as indicated by collapse must be treated with stimulants, whereas nervous excite ment may be controlled by sedatives as pot. bromid. or chloral hydras.
In an endeavour to relieve the congestion commonly occurring in the brain and lungs, intravenous injections of adrenalin might be found useful.
To prevent the excessive contraction which often occurs after the healing of large burns or scalds, the parts should be kept stretched as much as possible during the latter portion of their healing and frequently smeared with an oily dressing. Splints may be of assistance in some cases, but daily manual manipulation is usually sufficient. In the larger animals a number of elliptical pieces of skin may be excised on either side of the wound in the line of contraction and in healing will exert a"pull"upon the cicatrix. To avoid adhesions, con tiguous parts of the body such as the arm and breast may be kept apart by the application of pads of oiled wool held in position by means of bandages. Skin grafting has not as yet found many exponents among veterinary surgeons, but one or two successful cases have been reported.