Rodent cancer originates in the glands of the skin, and presents a special tendency to break down and ulcerate on the surface (Figs. 102 and 103). It almost never infects the lymph glands.

DERMOIDS

A dermoid is a tumour containing skin or mucous membrane, occurring in a situation where these tissues are not met under normal conditions.

The skin dermoid, or derma-cyst as it has been called by Askanazy, arises from a portion of epiblast, which has become sequestrated during the process of coalescence of two cutaneous surfaces in development. This form is therefore most frequently met with on the face and neck in the situations which correspond to the various clefts and fissures of the embryo. It occurs also on the trunk in situations where the lateral halves of the body coalesce during development. Such a dermoid usually takes the form of a globular cyst, the wall of which consists of skin, and the contents of turbid fluid containing desquamated epithelium, fat droplets, cholestrol crystals, and detached hairs. Delicate hairs may also be found projecting from the epithelial lining of the cyst.

Faulty coalescence of the cutaneous covering of the back occurs most frequently over the lower sacral vertebrae, giving rise to small congenital recesses, known as post-anal dimples and coccygeal sinuses. These recesses are lined with skin, which is furnished with hairs, sebaceous and sweat glands. If the external orifice becomes occluded, there results a dermoid cyst.

Tubulo-dermoids arise from embryonic ducts and passages that are normally obliterated at birth, for example, lingual dermoids develop in relation to the thyreo-glossal duct; rectal and post-rectal dermoids to the post-anal gut; and branchial dermoids in relation to the branchial clefts. Tubulo-dermoids present the same structure as skin dermoids, save that mucous membrane takes the place of skin in the wall of the cyst, and the contents consist of the pent-up secretion of mucous glands.

Clinical Features.—Although dermoids are of congenital origin, they are rarely evident at birth, and may not give rise to visible tumours until puberty, when the skin and its appendages become more active, or not till adult life. Superficial dermoids, such as those met with at the outer angle of the orbit, form rounded, definitely limited tumours over which the skin is freely movable. They are usually adherent to the deeper parts, and when situated over the skull may be lodged in a depression or actual gap in the bone. Sometimes the cyst becomes infected and suppurates, and finally ruptures on the surface. This may lead to a natural cure, or a persistent sinus may form. Dermoids more deeply placed, such as those within the thorax, or those situated between the rectum and sacrum, give rise to difficulty in diagnosis, even with the help of the X-rays, and their nature is seldom recognised until the escape of the contents—particularly hairs—supplies the clue. The literature of dermoid cysts is full of accounts of puzzling tumours met with in all sorts of situations.

The treatment is to remove the cyst. When it is impossible to remove the whole of the lining membrane by dissection, the portion that is left should be destroyed with the cautery.

Ovarian Dermoids.—Dermoids are not uncommon in the ovary (Fig. 59). They usually take the form of unilocular or multilocular cysts, the wall of which contains skin, mucous membrane, hair follicles, sebaceous, sweat, and mucous glands, nails, teeth, nipples, and mammary glands. The cavity of the cyst usually contains a pultaceous mixture of shed epithelium, fluid fat, and hair. If the cyst ruptures, the epithelial elements are diffused over the peritoneum, and may give rise to secondary dermoids.



The ovarian dermoid appears clinically as an abdominal or pelvic tumour provided with a pedicle; if the pedicle becomes twisted, the tumour undergoes strangulation, an event which is attended with urgent symptoms, not unlike those of strangulated hernia.

The treatment consists in removing the tumour by laparotomy.

Teratoma.—A teratoma is believed to result from partial dichotomy or cleavage of the trunk axis of the embryo, and is found exclusively in connection with the skull and vertebral column. It may take the form of a monstrosity such as conjoined twins or a parasitic foetus, but more commonly it is met with as an irregularly shaped tumour, usually growing from the sacrum. On dissection, such a tumour is found to contain a curious mixture of tissues—bones, skin, and portions of viscera, such as the intestine or liver. The question of the removal of the tumour requires to be considered in relation to the conditions present in each individual case.

CYSTS[3]

[3] Cysts which form in relation to new-growths have been considered with tumours.

Cysts are rounded sacs, the wall being composed of fibrous tissue lined by epithelium or endothelium; the contents are fluid or semi-solid, and vary in character according to the tissue in which the cyst has originated.

Retention and Exudation Cysts.—Retention cysts develop when the duct of a secreting gland is partly obstructed; the secretion accumulates, and the gland and its duct become distended into a cyst. They are met with in the mamma and in the salivary glands. Sebaceous cysts or wens are described with diseases of the skin. Exudation cysts arise from the distension of cavities which are not provided with excretory ducts, such as those in the thyreoid.

Implantation cysts are caused by the accidental transference of portions of the epidermis into the underlying connective tissue, as may occur in wounds by needles, awls, forks, or thorns. The implanted epidermis proliferates and forms a small cyst. They are met with chiefly on the palmar aspect of the fingers, and vary in size from a split pea to a cherry. The treatment consists in removing them by dissection.

Parasitic cysts are produced by the growth within the tissues of cyst-forming parasites, the best known being the taenia echinococcus, which gives rise to the hydatid cyst. The liver is by far the most common site of hydatid cysts in the human subject.

With regard to the further life-history of hydatids, the living elements of the cyst may die and degenerate, or the cyst may increase in size until it ruptures. As a result of pyogenic infection the cyst may be converted into an abscess.

The clinical features of hydatids vary so much with their situation and size, that they are best discussed with the individual organs. In general it may be said that there is a slow formation of a globular, elastic, fluctuating, painless swelling. Fluctuation is detected when the cyst approaches the surface, and it is then also that percussion may elicit the "hydatid thrill" or fremitus. This thrill is not often obtainable, and in any case is not pathognomonic of hydatids, as it may be elicited in ascites and in other abdominal cysts. Pressure of the cyst upon adjacent structures, and the occurrence of suppuration, are attended with characteristic clinical features.

The diagnosis of hydatids will be considered with the individual organs. The disease is more common in certain parts of Australia and in Shetland and Iceland than in countries where the association of dogs in the domestic life of the inhabitants is less intimate. Pfeiler, who has worked at the serum diagnosis of hydatid disease, regards the complement deviation method as the most reliable; he believes that a positive reaction may almost be regarded as absolutely diagnostic of an echinococcal lesion.

The treatment is to excise the cyst completely, or to inject into it a 1 per cent. solution of formalin. In operating upon hydatids the utmost care must be taken to avoid leakage of the contents of the cyst, as these may readily disseminate the infection.

A blood cyst or haematoma results from the encapsulation of extravasated blood in the tissues, from haemorrhage taking place into a preformed cyst, or from the saccular pouching of a varicose vein.

A lymph cyst usually results from a contusion in which the skin is forcibly displaced from the subjacent tissues, and lymph vessels are thereby torn across. The cyst is usually situated between the skin and fascia, and contains clear or blood-stained serum. At first it is lax and fluctuates readily, later it becomes larger and more tense. The treatment consists in drawing off the contents through a hollow needle and applying firm pressure. Apart from injury, lymph cysts are met with as the result of the distension of lymph spaces and vessels (lymphangiectasis); and in lymphangiomas, of which the best-known example is the cystic hygroma or hydrocele of the neck.

GANGLION

This term is applied to a cyst filled with a clear colourless jelly or colloid material, met with in the vicinity of a joint or tendon sheath.

The commonest variety—the carpal ganglion—popularly known as a sprained sinew—is met with as a smooth, rounded, or oval swelling on the dorsal aspect of the carpus, usually towards its radial side (Fig. 60). It is situated over one of the intercarpal or other joints in this region, and may be connected with one or other of the extensor tendons. The skin and fascia are movable over the cyst. The cyst varies in size from a pea to a pigeon's egg, and usually attains its maximum size within a few months and then remains stationary. It becomes tense and prominent when the hand is flexed towards the palm. Its appearance is usually ascribed to some strain of the wrist—for example, in girls learning gymnastics. It may cause no symptoms or it may interfere with the use of the hand, especially in grasping movements and when the hand is dorsiflexed. In girls it may give rise to pain which shoots up the arm. Ganglia are also met with on the dorsum of the metacarpus and on the palmar aspect of the wrist.



The tarsal ganglion is situated on the dorsum of the foot over one or other of the intertarsal joints. It is usually smaller, flatter, and more tense than that met with over the wrist, so that it is sometimes mistaken for a bony tumour. It rarely causes symptoms, unless so situated as to be pressed upon by the boot.

Ganglia in the region of the knee are usually situated over the interval between the femur and tibia, most often on the lateral aspect of the joint in front of the tendon of the biceps (Fig. 61). The swelling, which may attain the size of half a walnut, is tense and hard when the knee is extended, and becomes softer and more prominent when it is flexed. They are met with in young adults who follow laborious occupations or who indulge in athletics, and they cause stiffness, discomfort, and impairment of the use of the limb. A ganglion is sometimes met with on the median aspect of the head of the metatarsal bone of the great toe and may be the cause of considerable suffering; it is indistinguishable from the thickened and enlarged bursa so commonly present in this situation in the condition known as bunion.



Ganglionic cysts are met with in other situations than those mentioned, but they are so rare as not to require separate description.

Ganglia are to be diagnosed by their situation and physical characters; enlarged bursae, synovial cysts, and new-growths are the swellings most likely to be mistaken for them. The diagnosis is sometimes only cleared up by withdrawing the clear, jelly-like contents through a hollow needle.

Pathological Anatomy.—The wall of the cyst is composed of fibrous tissue closely adherent to or fused with the surrounding tissues, so that it cannot be shelled out. There is no endothelial lining, and the fibrous tissue of the wall is in immediate contact with the colloid material in the interior, which appears to be derived by a process of degeneration from the surrounding connective tissue. In the region of the knee the ganglion is usually multilocular, and consists of a meshwork of fibrous tissue, the meshes of which are occupied by colloid material.

It is often stated that a ganglion originates from a hernial protrusion of the synovial membrane of a joint or tendon sheath. We have not been able to demonstrate any communication between the cavity of the cyst and that of an adjacent tendon sheath or joint. It is possible, however, that the cyst may originate from a minute portion of synovial membrane being protruded and strangulated so that it becomes disconnected from that to which it originally belonged; it may then degenerate and give rise to colloid material, which accumulates and forms a cyst. Ledderhose and others regard ganglia as entirely new formations in the peri-articular tissues, resulting from colloid degeneration of the fibrous tissue of the capsular ligament, occurring at first in numerous small areas which later coalesce. Ganglia are probably, therefore, of the nature of degeneration cysts arising in the capsule of joints, in tendons, and in their sheaths.

Treatment.—A ganglion can usually be got rid of by a modification of the old-fashioned seton. The skin and cyst wall are transfixed by a stout needle carrying a double thread of silkworm gut; some of the colourless jelly escapes from the punctures; the ends of the thread are tied and cut short, and a dressing is applied. A week later the threads are removed and the minute punctures are sealed with collodion. The action of the threads is to convert the cyst wall into granulation tissue, which undergoes the usual conversion into scar tissue. If the cyst re-forms, it should be removed by open dissection under local anaesthesia. Puncture with a tenotomy knife and scraping the interior, and the injection of irritants, are alternative, but less satisfactory, methods of treatment.

Ganglia in the substance of tendons are rare. The diagnosis rests on the observation that the small tumour is cystic, and that it follows the movements of the tendon. The cyst is at first multiple, but the partitions disappear, and the spaces are thrown into one. The tendon is so weakened that it readily ruptures. The best treatment is to resect the affected segment of tendon.

The so-called "compound palmar ganglion" is a tuberculous disease of the tendon sheaths, and is described with diseases of tendon sheaths.



CHAPTER XI

INJURIES

CONTUSIONS—WOUNDS: Varieties—WOUNDS BY FIREARMS AND EXPLOSIVES: Pistol-shot wounds; Wounds by sporting guns; Wounds by rifle bullets; Wounds received in warfare; Shell wounds. Embedded foreign bodies—BURNS AND SCALDS—INJURIES PRODUCED BY ELECTRICITY: X-ray and radium; Electrical burns; Lightning stroke.

CONTUSIONS

A contusion or bruise is a laceration of the subcutaneous soft tissues, without solution of continuity of the skin. When the integument gives way at the same time, a contused-wound results. Bruising occurs when force is applied to a part by means of a blunt object, whether as a direct blow, a crush, or a grazing form of violence. If the force acts at right angles to the part, it tends to produce localised lesions which extend deeply; while, if it acts obliquely, it gives rise to lesions which are more diffuse, but comparatively superficial. It is well to remember that those who suffer from scurvy, or haemophilia (bleeders), and fat and anaemic females, are liable to be bruised by comparatively trivial injuries.

Clinical Features.—The less severe forms of contusion are associated with ecchymosis, numerous minute and discrete punctate haemorrhages being scattered through the superficial layers of the skin, which is slightly oedematous. The effused blood is soon reabsorbed.

The more severe forms are attended with extravasation, the extravasated blood being widely diffused through the cellular tissue of the part, especially where this is loose and lax, as in the region of the orbit, the scrotum and perineum, and on the chest wall. A blue or bluish-black discoloration occurs in patches, varying in size and depth with the degree of force which produced the injury, and in shape with the instrument employed. It is most intense in regions where the skin is naturally thin and pigmented. In parts where the extravasated blood is only separated from the oxygen of the air by a thin layer of epidermis or by a mucous membrane, it retains its bright arterial colour. These points are often well illustrated in cases of black eye, where the blood effused under the conjunctiva is bright red, while that in the eyelids is almost black. In severe contusions associated with great tension of the skin—for example, over the front of the tibia or around the ankle—blisters often form on the surface and constitute a possible avenue of infection. When deeply situated, the blood tends to spread along the lines of least resistance, partly under the influence of gravity, passing under fasciae, between muscles, along the sheaths of vessels, or in connective-tissue spaces, so that it may only reach the surface after some time, and at a considerable distance from the seat of injury. This fact is sometimes of importance in diagnosis, as, for example, in certain fractures of the base of the skull, where discoloration appears under the conjunctiva or behind the mastoid process some days after the accident.

Blood extravasated deeply in the tissues gives rise to a firm, resistant, doughy swelling, in which there may be elicited on deep palpation a peculiar sensation, not unlike the crepitus of fracture.

It frequently happens that, from the tearing of lymph vessels, serous fluid is extravasated, and a lymphatic or serous cyst may form.

In all contusions accompanied by extravasation, there is marked swelling of the area involved, as well as pain and tenderness. The temperature may rise to 101 F., or, in the large extravasations that occur in bleeders, even higher—a form of aseptic fever. The degree of shock is variable, but sudden syncope frequently results from severe bruises of the testicle, abdomen, or head, and occasionally marked nervous depression follows these injuries.

Contusion of muscles or nerves may produce partial atrophy and paresis, as is often seen after injuries in the region of the shoulder.

In alcoholic or other debilitated patients, suppuration is liable to ensue in bruised parts, infection taking place from cocci circulating in the blood, or through the overlying skin.

Terminations of Contusions.—The usual termination is a complete return to the normal, some of the extravasated blood being organised, but most of it being reabsorbed. During the process characteristic alterations in the colour of the effused blood take place as a result of changes in the blood pigment. In from twenty-four to forty-eight hours the margins of the blue area become of a violet hue, and as time goes on the discoloured area increases in size, and becomes successively green, yellow, and lemon-coloured at its margins, the central part being the last to change. The rate at which this play of colours proceeds is so variable, and depends on so many circumstances, that no time-limits can be laid down. During the disintegration of the effused blood the adjacent lymph glands may become enlarged, and on dissection may be found to be pigmented. Sometimes the blood persists as a collection of fluid with a newly formed connective-tissue capsule, constituting a haematoma or blood cyst, more often met with in the scalp than in other parts.

The impairment of the blood supply of the skin may lead to the formation of blisters, or to necrosis. Death of skin is more liable to occur in bleeders, and when the slough separates the blood-clot is exposed and the reparative changes go on extremely slowly. Suppuration may occur and lead to the formation of an abscess as a result of direct infection from the skin or through the circulation.

Treatment.—If the patient is seen immediately after the accident, elevation of the part, and firm pressure applied by means of a thick pad of cotton wool and an elastic bandage, are useful in preventing effusion of blood. Ice-bags and evaporating lotions are to be used with caution, as they are liable to lower the vitality of the damaged tissues and lead to necrosis of the skin.

When extravasation has already taken place, massage is the most speedy and efficacious means of dispersing the effused blood. The part should be massaged several times a day, unless the presence of blebs or abrasions of the skin prevents this being done. When this is the case, the use of antiseptic dressings is called for to prevent infection and to promote healing, after which massage is employed.

When the tension caused by the extravasated blood threatens the vitality of the skin, incisions may be made, if asepsis can be assured. The blood from a haematoma may be withdrawn by an exploring needle, and the puncture sealed with collodion. Infective complications must be looked for and dealt with on general principles.

WOUNDS

A wound is a solution in the continuity of the skin or mucous membrane and of the underlying tissues, caused by violence.

Three varieties of wounds are described: incised, punctured, and contused and lacerated.

Incised Wounds.—Typical examples of incised wounds are those made by the surgeon in the course of an operation, wounds accidentally inflicted by cutting instruments, and suicidal cut-throat wounds. It should be borne in mind in connection with medico-legal inquiries, that wounds of soft parts that closely overlie a bone, such as the skull, the tibia, or the patella, although, inflicted by a blunt instrument, may have all the appearances of incised wounds.

Clinical Features.—One of the characteristic features of an incised wound is its tendency to gape. This is evident in long skin wounds, and especially when the cut runs across the part, or when it extends deeply enough to divide muscular fibres at right angles to their long axis. The gaping of a wound, further, is more marked when the underlying tissues are in a state of tension—as, for example, in inflamed parts. Incised wounds in the palm of the hand, the sole of the foot, or the scalp, however, have little tendency to gape, because of the close attachment of the skin to the underlying fascia.

Incised wounds, especially in inflamed tissues, tend to bleed profusely; and when a vessel is only partly divided and is therefore unable to contract, it continues to bleed longer than when completely cut across.

The special risks of incised wounds are: (1) division of large blood vessels, leading to profuse haemorrhage; (2) division of nerve-trunks, resulting in motor and sensory disturbances; and (3) division of tendons or muscles, interfering with movement.

Treatment.—If haemorrhage is still going on, it must be arrested by pressure, torsion, or ligature, as the accumulation of blood in a wound interferes with union. If necessary, the wound should be purified by washing with saline solution or eusol, and the surrounding skin painted with iodine, after which the edges are approximated by sutures. The raw surfaces must be brought into accurate apposition, care being taken that no inversion of the cutaneous surface takes place. In extensive and deep wounds, to ensure more complete closure and to prevent subsequent stretching of the scar, it is advisable to unite the different structures—muscles, fasciae, and subcutaneous tissue—by separate series of buried sutures of catgut or other absorbable material. For the approximation of the skin edges, stitches of horse-hair, fishing-gut, or fine silk are the most appropriate. These stitches of coaptation may be interrupted or continuous. In small superficial wounds on exposed parts, stitch marks may be avoided by approximating the edges with strips of gauze fixed in position by collodion, or by subcutaneous sutures of fine catgut. Where the skin is loose, as, for example, in the neck, on the limbs, or in the scrotum, the use of Michel's clips is advantageous in so far as these bring the deep surfaces of the skin into accurate apposition, are introduced with comparatively little pain, and leave only a slight mark if removed within forty-eight hours.

When there is any difficulty in bringing the edges of the wound into apposition, a few interrupted relaxation stitches may be introduced wide of the margins, to take the strain off the coaptation stitches. Stout silk, fishing-gut, or silver wire may be employed for this purpose. When the tension is extreme, Lister's button suture may be employed. The tension is relieved and death of skin prevented by scoring it freely with a sharp knife. Relaxation stitches should be removed in four or five days, and stitches of coaptation in from seven to ten days. On the face and neck, wounds heal rapidly, and stitches may be removed in two or three days, thus diminishing the marks they leave.

Drainage.—In wounds in which no cavity has been left, and in which there is no reason to suspect infection, drainage is unnecessary. When, however, the deeper parts of an extensive wound cannot be brought into accurate apposition, and especially when there is any prospect of oozing of blood or serum—as in amputation stumps or after excision of the breast—drainage is indicated. It is a wise precaution also to insert drainage tubes into wounds in fat patients when there is the slightest reason to suspect the presence of infection. Glass or rubber tubes are the best drains; but where it is desirable to leave little mark, a few strands of horse-hair, or a small roll of rubber, form a satisfactory substitute. Except when infection occurs, the drain is removed in from one to four days and the opening closed with a Michel's clip or a suture.

Punctured Wounds.—Punctured wounds are produced by narrow, pointed instruments, and the sharper and smoother the instrument the more does the resulting injury resemble an incised wound; while from more rounded and rougher instruments the edges of the wound are more or less contused or lacerated. The depth of punctured wounds greatly exceeds their width, and the damage to subcutaneous parts is usually greater than that to the skin. When the instrument transfixes a part, the edges of the wound of entrance may be inverted, and those of the exit wound everted. If the instrument is a rough one, these conditions may be reversed by its sudden withdrawal.

Punctured wounds neither gape nor bleed much. Even when a large vessel is implicated, the bleeding usually takes place into the tissues rather than externally.

The risks incident to this class of wounds are: (1) the extreme difficulty, especially when a dense fascia has been perforated, of rendering them aseptic, on account of the uncertainty as to their depth, and of the way in which the surface wound closes on the withdrawal of the instrument; (2) different forms of aneurysm may result from the puncture of a large vessel; (3) perforation of a joint, or of a serous cavity, such as the abdomen, thorax, or skull, materially adds to the danger.

Treatment.—The first indication is to purify the whole extent of the wound, and to remove any foreign body or blood-clot that may be in it. It is usually necessary to enlarge the wound, freely dividing injured fasciae, paring away bruised tissues, and purifying the whole wound-surface. Any blood vessel that is punctured should be cut across and tied; and divided muscles, tendons, or nerves must be sutured. After haemorrhage has been arrested, iodoform and bismuth paste is rubbed into the raw surface, and the wound closed. If there is any reason to doubt the asepticity of the wound, it is better treated by the open method, and a Bier's bandage should be applied.

Contused and Lacerated Wounds.—These may be considered together, as they so occur in practice. They are produced by crushing, biting, or tearing forms of violence—such as result from machinery accidents, firearms, or the bites of animals. In addition to the irregular wound of the integument, there is always more or less bruising of the parts beneath and around, and the subcutaneous lesions are much wider than appears on the surface.

Wounds of this variety usually gape considerably, especially when there is much laceration of the skin. It is not uncommon to have considerable portions of skin, muscle, or tendon completely torn away.

Haemorrhage is seldom a prominent feature, as the crushing or tearing of the vessel wall leads to the obliteration of the lumen.

The special risks of these wounds are: (1) Sloughing of the bruised tissues, especially when attempts to sterilise the wound have not been successful. (2) Reactionary haemorrhage after the initial shock has passed off. (3) Secondary haemorrhage as a result of infective processes ensuing in the wound. (4) Loss of muscle or tendon, interfering with motion. (5) Cicatricial contraction. (6) Gangrene, which may follow occlusion of main vessels, or virulent infective processes. (7) It is not uncommon to have particles of carbon embedded in the tissues after lacerated wounds, leaving unsightly, pigmented scars. This is often seen in coal-miners, and in those injured by firearms, and is to be prevented by removing all gross dirt from the edges of the wound.

Treatment.—In severe wounds of this class implicating the extremities, the most important question that arises is whether or not the limb can be saved. In examining the limb, attention should first be directed to the state of the main blood vessels, in order to determine if the vascular supply of the part beyond the lesion is sufficient to maintain its vitality. Amputation is usually called for if there is complete absence of pulsation in the distal arteries and if the part beyond is cold. If at the same time important nerve-trunks are lacerated, so that the function of the limb would be seriously impaired, it is not worth running the risk of attempting to save it. If, in addition, there is extensive destruction of large muscular masses or of important tendons, or comminution of the bones, amputation is usually imperative. Stripping of large areas of skin is not in itself a reason for removing a limb, as much can be done by skin grafting, but when it is associated with other lesions it favours amputation. In considering these points, it must be borne in mind that the damage to the deeper tissues is always more extensive than appears on the surface, and that in many cases it is only possible to estimate the real extent of the injury by administering an anaesthetic and exploring the wound. In doubtful cases the possibility of rendering the parts aseptic will often decide the question for or against amputation. If thorough purification is accomplished, the success which attends conservative measures is often remarkable. It is permissible to run an amount of risk to save an upper extremity which would be unjustifiable in the case of a lower limb. The age and occupation of the patient must also be taken into account.

It having been decided to try and save the limb, the question is only settled for the moment; it may have to be reconsidered from day to day, or even from hour to hour, according to the progress of the case.

When it is decided to make the attempt to save the limb, the wound must be thoroughly purified. All bruised tissue in which gross dirt has become engrained should be cut away with knife or scissors. The raw surface is then cleansed with eusol, washed with sterilised salt solution followed by methylated spirit, and rubbed all over with "bipp" paste. If the purification is considered satisfactory the wound may be closed, otherwise it is left open, freely drained or packed with gauze, and the limb is immobilised by suitable splints.

WOUNDS BY FIREARMS AND EXPLOSIVES

It is not necessary here to do more than indicate the general characters of wounds produced by modern weapons. For further details the reader is referred to works on military surgery. Experience has shown that the nature and severity of the injuries sustained in warfare vary widely in different campaigns, and even in different fields of the same campaign. Slight variations in the size, shape, and weight of rifle bullets, for example, may profoundly modify the lesions they produce: witness the destructive effect of the pointed bullet compared with that of the conical form previously used. The conditions under which the fighting is carried on also influence the wounds. Those sustained in the open, long-range fighting of the South African campaign of 1899-1902 were very different from those met with in the entrenched warfare in France in 1914-1918. It has been found also that the infective complications are greatly influenced by the terrain in which the fighting takes place. In the dry, sandy, uncultivated veldt of South Africa, bullet wounds seldom became infected, while those sustained in the highly manured fields of Belgium were almost invariably contaminated with putrefactive organisms, and gaseous gangrene and tetanus were common complications. It has been found also that wounds inflicted in naval engagements present different characters from those sustained on land. Many other factors, such as the physical and mental condition of the men, the facilities for affording first aid, and the transport arrangements, also play a part in determining the nature and condition of the wounds that have to be dealt with by military surgeons.

Whatever the nature of the weapon concerned, the wound is of the punctured, contused, and lacerated variety. Its severity depends on the size, shape, and velocity of the missile, the range at which the weapon is discharged, and the part of the body struck.

Shock is a prominent feature, but its degree, as well as the time of its onset, varies with the extent and seat of the injury, and with the mental state of the patient when wounded. We have observed pronounced shock in children after being shot even when no serious injury was sustained. At the moment of injury the patient experiences a sensation which is variously described as being like the lash of a whip, a blow with a stick, or an electric shock. There is not much pain at first, but later it may become severe, and is usually associated with intense thirst, especially when much blood has been lost.

In all forms of wounds sustained in warfare, septic infection constitutes the main risk, particularly that resulting from streptococci. The presence of anaerobic organisms introduces the additional danger of gaseous forms of gangrene.

The earlier the wound is disinfected the greater is the possibility of diminishing this risk. If cleansing is carried out within the first six hours the chance of eliminating sepsis is good; with every succeeding six hours it diminishes, until after twenty-four hours it is seldom possible to do more than mitigate sepsis. (J. T. Morrison.)

The presence of a metallic foreign body having been determined and its position localised by means of the X-rays, all devitalised and contaminated tissue is excised, the foreign material, e.g., a missile, fragments of clothing, gravel and blood-clot, removed, the wound purified with antiseptics and closed or drained according to circumstances.

Pistol-shot Wounds.—Wounds inflicted by pistols, revolvers, and small air-guns are of frequent occurrence in civil practice, the weapon being discharged usually by accident, but frequently with suicidal, and sometimes with homicidal intent.

With all calibres and at all ranges, except actual contact, the wound of entrance is smaller than the bullet. If the weapon is discharged within a foot of the body, the skin surrounding the wound is usually stained with powder and burned, and the hair singed. At ranges varying from six inches to thirty feet, grains of powder may be found embedded in the skin or lying loose on the surface, the greater the range the wider being the area of spread. When black powder is used, the embedded grains usually leave a permanent bluish-black tattooing of the skin. When the weapon is placed in contact with the skin, the subcutaneous tissues are lacerated over an area of two or three inches around the opening made by the bullet and smoke and powder-staining and scorching are more marked than at longer ranges.

When the bullet perforates, the exit wound is usually larger and more extensively lacerated than the wound of entrance. Its margins are as a rule everted, and it shows no marks of flame, smoke, or powder. These features are common to all perforations caused by bullets.

Pistol wounds only produce dangerous effects when fired at close range, and when the cavities of the skull, the thorax, or the abdomen are implicated. In the abdomen a lethal injury may readily be caused even by pistols of the "toy" order. These injuries will be described with regional surgery.

Pistol-shot wounds of joints and soft parts are seldom of serious import apart from the risk of haemorrhage and of infection.

Treatment.—The treatment of wounds of the soft parts consists in purifying the wounds of entrance and exit and the surrounding skin, and in providing for drainage if this is indicated.

There being no urgency for the removal of the bullet, time should be taken to have it localised by the X-rays, preferably by stereoscopic plates. In some cases it is not necessary to remove the bullet.

Wounds by Sporting Guns.—In the common sporting or scatter gun, with which accidents so commonly occur during the shooting season, the charge of small shot or pellets leave the muzzle of the gun as a solid mass which makes a single ragged wound having much the appearance of that caused by a single bullet. At a distance of from four to five feet from the muzzle the pellets begin to disperse so that there are separate punctures around the main central wound. As the range increases, these outlying punctures make a wider and wider pattern, until at a distance of from eighteen to twenty feet from the muzzle, the scattering is complete, there is no longer any central wound, and each individual pellet makes its own puncture. From these elementary data, it is usually possible, from the features of the wound, to arrive at an approximately accurate conclusion regarding the range at which the gun was discharged, and this may have an important bearing on the question of accident, suicide, or murder.

As regards the effects on the tissues at close range, that is, within a few feet, there is widespread laceration and disruption; if a bone is struck it is shattered, and portions of bone may be displaced or even driven out through the exit wound.

When the charge impinges over one of the large cavities of the body, the shot may scatter widely through the contained viscera, and there is often no exit wound. In the thorax, for example, if a rib is struck, the charge and possibly fragments of bone, will penetrate the pleura, and be dispersed throughout the lung; in the head, the skull may be shattered and the brain torn up; and in the abdomen, the hollow viscera may be perforated in many places and the solid organs lacerated.

On covered parts the clothing, by deflecting the shot, influences the size and shape of the wound; the entrance wound is increased in size and more ragged, and portions of the clothes may be driven into the tissues.



A charge of small shot is much more destructive to blood vessels, tendons, and ligaments than a single bullet, which in many cases pushes such structures aside without dividing them. In the abdomen and chest, also, the damage done by a full charge of shot is much more extensive than that inflicted by a single bullet, the deflection of the pellets leading to a greater number of perforations of the intestine and more widespread laceration of solid viscera.

When the charge impinges on one of the extremities at close range, we often have the opportunity of observing that the exit wound is larger, more ragged than that of entrance, and that its edges are everted; the extensive tearing and bruising of all the tissues, including the bones, and the marked tendency to early and progressive septic infection, render amputation compulsory in the majority of such cases.

At a range of from twenty to thirty feet, although the scatter is complete, the pellets are still close together, so that if they encounter the shaft of a long bone, even the femur, they fracture the bone across, often along with some longitudinal splintering.

Individual pellets striking the shafts of long bones become flattened or distorted, and when cancellated bone is struck they become embedded in it (Fig. 62).

The skin, when it is closely peppered with shot, is liable to lose its vitality, and with the addition of a little sepsis, readily necroses and comes away as a slough.

When the shot have diverged so as to strike singly, they seldom do much harm, but fatal damage may be done to the brain or to the aorta, or the eye may be seriously injured by a single pellet.

Small shot fired at longer ranges—over about a hundred and fifty feet—usually go through the skin, but seldom pierce the fascia, and lie embedded in the subcutaneous tissue, from which they can readily be extracted.

The wad of the cartridge behaves erratically: so long as it remains flat it goes off with the rest of the charge, and is often buried in the wound; but if it curls up or turns on its side, it is usually deflected and flies clear of the shot. It may make a separate wound.

Wounds from sporting guns are to be treated on the usual lines, the early efforts being directed to the alleviation of shock and the prevention of septic infection. There is rarely any urgency in the removal of pellets from the tissues.

Wounds by Rifle Bullets.—The vast majority of wounds inflicted by rifle bullets are met with in the field during active warfare, and fall to be treated by military surgeons. They occasionally occur accidentally, however, during range practice for example, and may then come under the notice of the civil surgeon.

It is only necessary here to consider the effects of modern small-bore rifle or machine-gun bullets.

The trajectory is practically flat up to 675 yards. In destructive effect there is not much difference between the various high velocity bullets used in different armies; they will kill up to a distance of two miles. The hard covering is employed to enable the bullet to take the grooves in the rifle, and to prevent it stripping as it passes through the barrel. It also increases the penetrating power of the missile, but diminishes its "stopping" power, unless a vital part or a long bone is struck. By removing the covering from the point of the bullet, as is done in the Dum-Dum bullet, or by splitting the end, the bullet is made to expand or "mushroom" when it strikes the body, and its stopping power is thereby greatly increased, the resulting wound being much more severe. These "soft-nosed" expanding bullets are to be distinguished from "explosive" bullets which contain substances which detonate on impact. High velocity bullets are unlikely to lodge in the body unless spent, or pulled up by a sandbag, or metal buckle on a belt, or a book in the pocket, or the core and the case separating—"stripping" of the bullet. Spent shot may merely cause bruising of the surface, or they may pass through the skin and lodge in the subcutaneous tissue, or may even damage some deeper structure such as a nerve trunk.

A blank cartridge fired at close range may cause a severe wound, and, if charged with black powder, may leave a permanent bluish-black pigmentation of the skin.

The lesions of individual tissues—bones, nerves, blood vessels—are considered with these.

Treatment of Gunshot Wounds under War Conditions.—It is only necessary to indicate briefly the method of dealing with gunshot wounds in warfare as practised in the European War.

1. On the Field.—Haemorrhage is arrested in the limbs by an improvised tourniquet; in the head by a pad and bandage; in the thorax or abdomen by packing if necessary, but this should be avoided if possible, as it favours septic infection. If a limb is all but detached it should be completely severed. A full dose of morphin is given hypodermically. The ampoule of iodine carried by the wounded man is broken, and its contents are poured over and around the wound, after which the field dressing is applied. In extensive wounds, the "shell-dressing" carried by the stretcher bearers is preferred. All bandages are applied loosely to allow for subsequent swelling. The fragments of fractured bones are immobilised by some form of emergency splint.

2. At the Advanced Dressing Station, after the patient has had a liberal allowance of warm fluid nourishment, such as soup or tea, a full dose of anti-tetanic serum is injected. The tourniquet is removed and the wound inspected. Urgent amputations are performed. Moribund patients are detained lest they die en route.

3. In the Field Ambulance or Casualty Clearing Station further measures are employed for the relief of shock, and urgent operations are performed, such as amputation for gangrene, tracheotomy for dyspnoea, or laparotomy for perforated or lacerated intestine. In the majority of cases the main object is to guard against infection; the skin is disinfected over a wide area and surrounded with towels; damaged tissue, especially muscle, is removed with the knife or scissors, and foreign bodies are extracted. Torn blood vessels, and, if possible, nerves and tendons are repaired. The wound is then partly closed, provision being made for free drainage, or some special method of irrigation, such as that of Carrel, is adopted. Sometimes the wound is treated with bismuth, iodoform, and paraffin paste (B.I.P.P.) and sutured.

4. In the Base Hospital or Hospital Ship various measures may be called for according to the progress of the wound and the condition of the patient.

Shell Wounds and Wounds produced by Explosions.—It is convenient to consider together the effects of the bursting of shells fired from heavy ordnance and those resulting in the course of blasting operations from the discharge of dynamite or other explosives, or from the bursting of steam boilers or pipes, the breaking of machinery, and similar accidents met with in civil practice.

Wounds inflicted by shell fragments and shrapnel bullets tend to be extensive in area, and show great contusion, laceration, and destruction of the tissues. The missiles frequently lodge and carry portions of the clothing and, it may be, articles from the man's pocket, with them. Shell wounds are attended with a considerable degree of shock. On account of the wide area of contusion which surrounds the actual wound produced by shell fragments, amputation, when called for, should be performed some distance above the torn tissues, as there is considerable risk of sloughing of the flaps.

Wounds produced by dynamite explosions and the bursting of boilers have the same general characters as shell wounds. Fragments of stone, coal, or metal may lodge in the tissues, and favour the occurrence of infective complications.

All such injuries are to be treated on the general principles governing contused and lacerated wounds.

EMBEDDED FOREIGN BODIES

In the course of many operations foreign substances are introduced into the tissues and intentionally left there, for example, suture and ligature materials, steel or aluminium plates, silver wire or ivory pegs used to secure the fixation of bones, or solid paraffin employed to correct deformities. Other substances, such as gauze, drainage tubes, or metal instruments, may be unintentionally left in a wound.

Foreign bodies may also lodge in accidentally inflicted wounds, for example, bullets, needles, splinters of wood, or fragments of clothing. The needles of hypodermic syringes sometimes break and a portion remains embedded in the tissues. As a result of explosions, particles of carbon, in the form of coal-dust or gunpowder, or portions of shale, may lodge in a wound.

The embedded foreign body at first acts as an irritant, and induces a reaction in the tissues in which it lodges, in the form of hyperaemia, local leucocytosis, proliferation of fibroblasts, and the formation of granulation tissue. The subsequent changes depend upon whether or not the wound is infected with pyogenic bacteria. If it is so infected, suppuration ensues, a sinus forms, and persists until the foreign body is either cast out or removed.

If the wound is aseptic, the fate of the foreign body varies with its character. A substance that is absorbable, such as catgut or fine silk, is surrounded and permeated by the phagocytes, which soften and disintegrate it, the debris being gradually absorbed in much the same manner as a fibrinous exudate. Minute bodies that are not capable of being absorbed, such as particles of carbon, or of pigment used in tattooing, are taken up by the phagocytes, and in course of time removed. Larger bodies, such as needles or bullets, which are not capable of being destroyed by the phagocytes, become encapsulated. In the granulation tissue by which they are surrounded large multinuclear giant-cells appear ("foreign-body giant-cells") and attach themselves to the foreign body, the fibroblasts proliferate and a capsule of scar tissue is eventually formed around the body. The tissues of the capsule may show evidence of iron pigmentation. Sometimes fluid accumulates around a foreign body within its capsule, constituting a cyst.

Substances like paraffin, strands of silk used to bridge a gap in a tendon, or portions of calcined bone, instead of being encapsulated, are gradually permeated and eventually replaced by new connective tissue.

Embedded bodies may remain in the tissues for an indefinite period without giving rise to inconvenience. At any time, however, they may cause trouble, either as a result of infective complications, or by inducing the formation of a mass of inflammatory tissue around them, which may simulate a gumma, a tuberculous focus, or a sarcoma. This latter condition may give rise to difficulties in diagnosis, particularly if there is no history forthcoming of the entrance of the foreign body. The ignorance of patients regarding the possible lodgment in the tissues of a foreign body—even of considerable size—is remarkable. In such cases the X-rays will reveal the presence of the foreign body if it is sufficiently opaque to cast a shadow. The heavy, lead-containing varieties of glass throw very definite shadows little inferior in sharpness and definition to those of metal; almost all the ordinary forms of commercial glass also may be shown up by the X-rays.

Foreign bodies encapsulated in the peritoneal cavity are specially dangerous, as the proximity of the intestine furnishes a constant possibility of infection.

The question of removal of the foreign body must be decided according to the conditions present in individual cases; in searching for a foreign body in the tissues, unless it has been accurately located, a general anaesthetic is to be preferred.

BURNS AND SCALDS

The distinction between a burn which results from the action of dry heat on the tissues of the body and a scald which results from the action of moist heat, has no clinical significance.

In young and debilitated subjects hot poultices may produce injuries of the nature of burns. In old people with enfeebled circulation mere exposure to a strong fire may cause severe degrees of burning, the clothes covering the part being uninjured. This may also occur about the feet, legs, or knees of persons while intoxicated who have fallen asleep before the fire.

The damage done to the tissues by strong caustics, such as fuming nitric acid, sulphuric acid, caustic potash, nitrate of silver, or arsenical paste, presents pathological and clinical features almost identical with those resulting from heat. Electricity and the Rontgen rays also produce lesions of the nature of burns.

Pathology of Burns.—Much discussion has taken place regarding the explanation of the rapidly fatal issue in extensive superficial burns. On post-mortem examination the lesions found in these cases are: (1) general hyperaemia of all the organs of the abdominal, thoracic, and cerebro-spinal cavities; (2) marked leucocytosis, with destruction of red corpuscles, setting free haemoglobin which lodges in the epithelial cells of the tubules of the kidneys; (3) minute thrombi and extravasations throughout the tissues of the body; (4) degeneration of the ganglion cells of the solar plexus; (5) oedema and degeneration of the lymphoid tissue throughout the body; (6) cloudy swelling of the liver and kidneys, and softening and enlargement of the spleen. Bardeen suggests that these morbid phenomena correspond so closely to those met with where the presence of a toxin is known to produce them, that in all probability death is similarly due to the action of some poison produced by the action of heat on the skin and on the proteins of the blood.

Clinical Features—Local Phenomena.—The most generally accepted classification of burns is that of Dupuytren, which is based upon the depth of the lesion. Six degrees are thus, recognised: (1) hyperaemia or erythema; (2) vesication; (3) partial destruction of the true skin; (4) total destruction of the true skin; (5) charring of muscles; (6) charring of bones.

It must be observed, however, that burns met with at the bedside always illustrate more than one of these degrees, the deeper forms always being associated with those less deep, and the clinical picture is made up of the combined characters of all. A burn is classified in terms of its most severe portion. It is also to be remarked that the extent and severity of a burn usually prove to be greater than at first sight appears.

Burns of the first degree are associated with erythema of the skin, due to hyperaemia of its blood vessels, and result from scorching by flame, from contact with solids or fluids below 212 F., or from exposure to the sun's rays. They are characterised clinically by acute pain, redness, transitory swelling from oedema, and subsequent desquamation of the surface layers of the epidermis. A special form of pigmentation of the skin is seen on the front of the legs of women from exposure to the heat of the fire.

Burns of Second Degree—Vesication of the Skin.—These are characterised by the occurrence of vesicles or blisters which are scattered over the hyperaemic area, and contain a clear yellowish or brownish fluid. On removing the raised epidermis, the congested and highly sensitive papillae of the skin are exposed. Unna has found that pyogenic bacteria are invariably present in these blisters. Burns of the second degree leave no scar but frequently a persistent discoloration. In rare instances the burned area becomes the seat of a peculiar overgrowth of fibrous tissue of the nature of keloid (p 401).

Burns of Third Degree—Partial Destruction of the Skin.—The epidermis and papillae are destroyed in patches, leaving hard, dry, and insensitive sloughs of a yellow or black colour. The pain in these burns is intense, but passes off during the first or second day, to return again, however, when, about the end of a week, the sloughs separate and expose the nerve filaments of the underlying skin. Granulations spring up to fill the gap, and are rapidly covered by epithelium, derived partly from the margins and partly from the remains of skin glands which have not been completely destroyed. These latter appear on the surface of the granulations as small bluish islets which gradually increase in size, become of a greyish-white colour, and ultimately blend with one another and with the edges. The resulting cicatrix may be slightly depressed, but otherwise exhibits little tendency to contract and cause deformity.

Burns of Fourth Degree—Total Destruction of the Skin.—These follow the more prolonged action of any form of intense heat. Large, black, dry eschars are formed, surrounded by a zone of intense congestion. Pain is less severe, and is referred to the parts that have been burned to a less degree. Infection is liable to occur and to lead to wide destruction of the surrounding skin. The amount of granulation tissue necessary to fill the gap is therefore great; and as the epithelial covering can only be derived from the margins—the skin glands being completely destroyed—the healing process is slow. The resulting scars are irregular, deep and puckered, and show a great tendency to contract. Keloid frequently develops in such cicatrices. When situated in the region of the face, neck, or flexures of joints, much deformity and impairment of function may result (Fig. 63).



In burns of the fifth degree the lesion extends through the subcutaneous tissue and involves the muscles; while in those of the sixth degree it passes still more deeply and implicates the bones. These burns are comparatively limited in area, as they are usually produced by prolonged contact with hot metal or caustics. Burns of the fifth and sixth degrees are met with in epileptics or intoxicated persons who fall into the fire. Large blood vessels, nerve-trunks, joints, or serous cavities may be implicated.

General Phenomena.—It is customary to divide the clinical history of a severe burn into three periods; but it is to be observed that the features characteristic of the periods have been greatly modified since burns have been treated on the same lines as other wounds.

The first period lasts for from thirty-six to forty-eight hours, during which time the patient remains in a more or less profound state of shock, and there is a remarkable absence of pain. When shock is absent or little marked, however, the amount of suffering may be great. When the injury proves fatal during this period, death is due to shock, probably aggravated by the absorption of poisonous substances produced in the burned tissues. In fatal cases there is often evidence of cerebral congestion and oedema.

The second period begins when the shock passes off, and lasts till the sloughs separate. The outstanding feature of this period is toxaemia, manifested by fever, the temperature rising to 102, 103, or 104 F., and congestive or inflammatory conditions of internal organs, giving rise to such clinical complications as bronchitis, broncho-pneumonia, or pleurisy—especially in burns of the thorax; or meningitis and cerebritis, when the neck or head is the seat of the burn. Intestinal catarrh associated with diarrhoea is not uncommon; and ulceration of the duodenum leading to perforation has been met with in a few cases. These phenomena are much more prominent when bacterial infection has taken place, and it seems probable that they are to be attributed chiefly to the infection, as they have become less frequent and less severe since burns have been treated like other breaches of the surface. Albuminuria is a fairly constant symptom in severe burns, and is associated with congestion of the kidneys. In burns implicating the face, neck, mouth, or pharynx, oedema of the glottis is a dangerous complication, entailing as it does the risk of suffocation.

The third period begins when the sloughs separate, usually between the seventh and fourteenth days, and lasts till the wound heals, its duration depending upon the size, depth, and asepticity of the raw area. The chief causes of death during this period are toxin absorption in any of its forms; waxy disease of the liver, kidneys, or intestine; less commonly erysipelas, tetanus, or other diseases due to infection by specific organisms. We have seen nothing to substantiate the belief that duodenal ulcers are liable to perforate during the third period.

The prognosis in burns depends on (1) the superficial extent, and, to a much less degree, the depth of the injury. When more than one-third of the entire surface of the body is involved, even in a mild degree, the prognosis is grave. (2) The situation of the burn is important. Burns over the serous cavities—abdomen, thorax, or skull—are, other things being equal, much more dangerous than burns of the limbs. The risk of oedema of the glottis in burns about the neck and mouth has already been referred to. (3) Children are more liable to succumb to shock during the early period, but withstand prolonged suppuration better than adults. (4) When the patient survives the shock, the presence or absence of infection is the all-important factor in prognosis.

Treatment.—The general treatment consists in combating the shock. When pain is severe, morphin must be injected.

Local Treatment.—The local treatment must be carried out on antiseptic lines, a general anaesthetic being administered, if necessary, to enable the purification to be carried out thoroughly. After carefully removing the clothing, the whole of the burned area is gently, but thoroughly, cleansed with peroxide of hydrogen or warm boracic lotion, followed by sterilised saline solution. As pyogenic bacteria are invariably found in the blisters of burns, these must be opened and the raised epithelium removed.

The dressings subsequently applied should meet the following indications: the relief of pain; the prevention of sepsis; and the promotion of cicatrisation.

An application which satisfactorily fulfils these requirements is picric acid. Pads of lint or gauze are lightly wrung out of a solution made up of picric acid, 1.5 drams; absolute alcohol, 3 ounces; distilled water, 40 ounces, and applied over the whole of the reddened area. These are covered with antiseptic wool, without any waterproof covering, and retained in position by a many-tailed bandage. The dressing should be changed once or twice a week, under the guidance of the temperature chart, any portion of the original dressing which remains perfectly dry being left undisturbed. The value of a general anaesthetic in dressing extensive burns, especially in children, can scarcely be overestimated.

Picric acid yields its best results in superficial burns, and it is useful as a primary dressing in all. As soon as the sloughs separate and a granulating surface forms, the ordinary treatment for a healing sore is instituted. Any slough under which pus has collected should be cut away with scissors to permit of free drainage.

An occlusive dressing of melted paraffin has also been employed. A useful preparation consists of: Paraffin molle 25 per cent., paraffin durum 67 per cent., olive oil 5 per cent., oil of eucalyptus 2 per cent., and beta-naphthol 1/4 per cent. It has a melting point of 48 C. It is also known as Ambrine and Burnol. After the burned area has been cleansed and thoroughly dried, it is sponged or painted with the melted paraffin, and before solidification takes place a layer of sterilised gauze is applied and covered with a second coating of paraffin. Further coats of paraffin are applied every other day to prevent the gauze sticking to the skin.

An alternative method of treating extensive burns is by immersing the part, or even the whole body when the trunk is affected, in a bath of boracic lotion kept at the body temperature, the lotion being frequently renewed.

If a burn is already infected when first seen, it is to be treated on the same principles as govern the treatment of other infected wounds.

All moist or greasy applications, such as Carron oil, carbolic oil and ointments, and all substances like collodion and dry powders, which retain discharges, entirely fail to meet the indications for the rational treatment of burns, and should be abandoned.

Skin-grafting is of great value in hastening healing after extensive burns, and in preventing cicatricial contraction. The deformities which are so liable to develop from contraction of the cicatrices are treated on general principles. In the region of the face, neck, and flexures of joints (Fig. 63), where they are most marked, the contracted bands may be divided and the parts stretched, the raw surface left being covered by Thiersch grafts or by flaps of skin raised from adjacent surfaces or from other parts of the body (Fig. 1).

INJURIES PRODUCED BY ELECTRICITY

Injuries produced by Exposure to X-Rays and Radium.—In the routine treatment of disease by radiations, injury is sometimes done to the tissues, even when the greatest care is exercised as to dosage and frequency of application. Robert Knox describes the following ill-effects.

Acute dermatitis varying in degree from a slight erythema to deep ulceration or even necrosis of skin. When ulcers form they are extremely painful and slow to heal. When hair-bearing areas are affected, epilation may occur without destroying the hair follicles and the hairs are reproduced, but if the reaction is excessive permanent alopecia may result.

Chronic dermatitis, which results from persistence of the acute form, is most intractable and may assume malignant characters. X-ray warts are a late manifestation of chronic dermatitis and may become malignant.

Among the late manifestations are neuritis, telangiectasis, and a painful and intractable form of ulceration, any of which may come on months or even years after the cessation of exposure. Sterility may be induced in X-ray workers who are imperfectly protected from the effects of the rays.

Electrical burns usually occur in those who are engaged in industrial undertakings where powerful electrical currents are employed.

The lesions—which vary from a slight superficial scorching to complete charring of parts—are most evident at the points of entrance and exit of the current, the intervening tissues apparently escaping injury.

The more superficial degrees of electrical burns differ from those produced by heat in being almost painless, and in healing very slowly, although as a rule they remain dry and aseptic.

The more severe forms are attended with a considerable degree of shock, which is not only more profound, but also lasts much longer than the shock in an ordinary burn of corresponding severity. The parts at the point of entrance of the current are charred to a greater or lesser depth. The eschar is at first dry and crisp, and is surrounded by a zone of pallor. For the first thirty-six to forty-eight hours there is comparatively little suffering, but at the end of that time the parts become exceedingly painful. In a majority of cases, in spite of careful purification, a slow form of moist gangrene sets in, and the slough spreads both in area and in depth, until the muscles and often the large blood vessels and nerves are exposed. A line of demarcation eventually forms, but the sloughs are exceedingly slow to separate, taking from three to five times as long as in an ordinary burn, and during the process of separation there is considerable risk of secondary haemorrhage from erosion of large vessels.

Treatment.—Electrical burns are treated on the same lines as ordinary burns, by thorough purification and the application of dry dressings, with a view to avoiding the onset of moist gangrene. After granulations have formed, skin-grafting is of value in hastening healing.

Lightning-stroke.—In a large proportion of cases lightning-stroke proves instantly fatal. In non-fatal cases the patient suffers from a profound degree of shock, and there may or may not be any external evidence of injury. In the mildest cases red spots or wheals—closely resembling those of urticaria—may appear on the body, but they usually fade again in the course of twenty-four hours. Sometimes large patches of skin are scorched or stained, the discoloured area showing an arborescent appearance. In other cases the injured skin becomes dry and glazed, resembling parchment. Appearances are occasionally met with corresponding to those of a superficial burn produced by heat. The chief difference from ordinary burns is the extreme slowness with which healing takes place. Localised paralysis of groups of muscles, or even of a whole limb, may follow any degree of lightning-stroke. Treatment is mainly directed towards combating the shock, the surface-lesions being treated on the same lines as ordinary burns.



CHAPTER XII

METHODS OF WOUND TREATMENT

Varieties of wounds—Modes of infection—Lister's work—Means taken to prevent infection of wounds: heat; chemical antiseptics; disinfection of hands; preparation of skin of patient; instruments; ligatures; dressings—Means taken to combat infection: purification; open-wound method.

The surgeon is called upon to treat two distinct classes of wounds: (1) those resulting from injury or disease in which the skin is already broken, or in which a communication with a mucous surface exists; and (2) those that he himself makes through intact skin, no infected mucous surface being involved.

Infection by bacteria must be assumed to have taken place in all wounds made in any other way than by the knife of the surgeon operating through unbroken skin. On this assumption the modern system of wound treatment is based. Pathogenic bacteria are so widely distributed, that in the ordinary circumstances of everyday life, no matter how trivial a wound may be, or how short a time it may remain exposed, the access of organisms to it is almost certain unless preventive measures are employed.

It cannot be emphasised too strongly that rigid precautions are to be taken to exclude fresh infection, not only in dealing with wounds that are free of organisms, but equally in the management of wounds and other lesions that are already infected. Any laxity in our methods which admits of fresh organisms reaching an infected wound adds materially to the severity of the infective process and consequently to the patient's risk.

There are many ways in which accidental infection may occur. Take, for example, the case of a person who receives a cut on the face by being knocked down in a carriage accident on the street. Organisms may be introduced to such a wound from the shaft or wheel by which he was struck, from the ground on which he lay, from any portion of his clothing that may have come in contact with the wound, or from his own skin. Or, again, the hands of those who render first aid, the water used to bathe the wound, the handkerchief or other extemporised dressing applied to it, may be the means of conveying bacterial infection. Should the wound open on a mucous surface, such as the mouth or nasal cavity, the organisms constantly present in such situations are liable to prove agents of infection.

Even after the patient has come under professional care the risks of his wound becoming infected are not past, because the hands of the doctor, his instruments, dressings, or other appliances may all, unless purified, become the sources of infection.

In the case of an operation carried out through unbroken skin, organisms may be introduced into the wound from the patient's own skin, from the hands of the surgeon or his assistants, through the medium of contaminated instruments, swabs, ligature or suture materials, or other things used in the course of the operation, or from the dressings applied to the wound.

Further, bacteria may gain access to devitalised tissues by way of the blood-stream, being carried hither from some infected area elsewhere in the body.

The Antiseptic System of Surgery.—Those who only know the surgical conditions of to-day can scarcely realise the state of matters which existed before the introduction of the antiseptic system by Joseph Lister in 1867. In those days few wounds escaped the ravages of pyogenic and other bacteria, with the result that suppuration ensued after most operations, and such diseases as erysipelas, pyaemia, and "hospital gangrene" were of everyday occurrence. The mortality after compound fractures, amputations, and many other operations was appalling, and death from blood-poisoning frequently followed even the most trivial operations. An operation was looked upon as a last resource, and the inherent risk from blood-poisoning seemed to have set an impassable barrier to the further progress of surgery. To the genius of Lister we owe it that this barrier was removed. Having satisfied himself that the septic process was due to bacterial infection, he devised a means of preventing the access of organisms to wounds or of counteracting their effects. Carbolic acid was the first antiseptic agent he employed, and by its use in compound fractures he soon obtained results such as had never before been attained. The principle was applied to other conditions with like success, and so profoundly has it affected the whole aspect of surgical pathology, that many of the infective diseases with which surgeons formerly had to deal are now all but unknown. The broad principles upon which Lister founded his system remain unchanged, although the methods employed to put them into practice have been modified.

Means taken to Prevent Infection of Wounds.—The avenues by which infective agents may gain access to surgical wounds are so numerous and so wide, that it requires the greatest care and the most watchful attention on the part of the surgeon to guard them all. It is only by constant practice and patient attention to technical details in the operating room and at the bedside, that the carrying out of surgical manipulations in such a way as to avoid bacterial infection will become an instinctive act and a second nature. It is only possible here to indicate the chief directions in which danger lies, and to describe the means most generally adopted to avoid it.

To prevent infection, it is essential that everything which comes into contact with a wound should be sterilised or disinfected, and to ensure the best results it is necessary that the efficiency of our methods of sterilisation should be periodically tested. The two chief agencies at our disposal are heat and chemical antiseptics.

Sterilisation by Heat.—The most reliable, and at the same time the most convenient and generally applicable, means of sterilisation is by heat. All bacteria and spores are completely destroyed by being subjected for fifteen minutes to saturated circulating steam at a temperature of 130 to 145 C. (= 266 to 293 F.). The articles to be sterilised are enclosed in a perforated tin casket, which is placed in a specially constructed steriliser, such as that of Schimmelbusch. This apparatus is so arranged that the steam circulates under a pressure of from two to three atmospheres, and permeates everything contained in it. Objects so sterilised are dry when removed from the steriliser. This method is specially suitable for appliances which are not damaged by steam, such, for example, as gauze swabs, towels, aprons, gloves, and metal instruments; it is essential that the efficiency of the steriliser be tested from time to time by a self-registering thermometer or other means.

The best substitute for circulating steam is boiling. The articles are placed in a "fish-kettle steriliser" and boiled for fifteen minutes in a 1 per cent. solution of washing soda.

To prevent contamination of objects that have been sterilised they must on no account be touched by any one whose hands have not been disinfected and protected by sterilised gloves.

Sterilisation by Chemical Agents.—For the purification of the skin of the patient, the hands of the surgeon, and knives and other instruments that are damaged by heat, recourse must be had to chemical agents. These, however, are less reliable than heat, and are open to certain other objections.

Disinfection of the Hands.—It is now generally recognised that one of the most likely sources of wound infection is the hands of the surgeon and his assistants. It is only by carefully studying to avoid all contact with infective matter that the hands can be kept surgically pure, and that this source of wound infection can be reduced to a minimum. The risk of infection from this source has further been greatly reduced by the systematic use of rubber gloves by house-surgeons, dressers, and nurses. The habitual use of gloves has also been adopted by the great majority of surgeons; the minority, who find they are handicapped by wearing gloves as a routine measure, are obliged to do so when operating in infective cases or dressing infected wounds, and in making rectal and vaginal examinations.

The gloves may be sterilised by steam, and are then put on dry, or by boiling, in which case they are put on wet. The gauntlet of the glove should overlap and confine the end of the sleeve of the sterilised overall, and the gloved hands are rinsed in lotion before and at frequent intervals during the operation. The hands are sterilised before putting on the gloves, preferably by a method which dehydrates the skin. Cotton gloves may be worn by the surgeon when tying ligatures, or between operations, and by the anaesthetist during operations on the head, neck, and chest.

The first step in the disinfection of the hands is the mechanical removal of gross surface dirt and loose epithelium by soap, a stream of running water as hot as can be borne, and a loofah or nail-brush, that has been previously sterilised by heat. The nails should be cut down till there is no sulcus between the nail edge and the pulp of the finger in which organisms may lodge. They are next washed for three minutes in methylated spirit to dehydrate the skin, and then for two or three minutes in 70 per cent. sublimate or biniodide alcohol (1 in 1000). Finally, the hands are rubbed with dry sterilised gauze.

Preparation of the Skin of the Patient.—In the purification of the skin of the patient before operation, reliance is to be placed chiefly in the mechanical removal of dirt and grease by the same means as are taken for the cleansing of the surgeon's hands. Hair-covered parts should be shaved. The skin is then dehydrated by washing with methylated spirit, followed by 70 per cent. sublimate or biniodide alcohol (1 in 1000). This is done some hours before the operation, and the part is then covered with pads of dry sterilised gauze or a sterilised towel. Immediately before the operation the skin is again purified in the same way.

The iodine method of disinfecting the skin introduced by Grossich is simple, and equally efficient. The day before operation the skin, after being washed with soap and water, is shaved, dehydrated by means of methylated spirit, and then painted with a 5 per cent. solution of iodine in rectified spirit. The painting with iodine is repeated just before the operation commences, and again after it is completed. The final application is omitted in the case of children. In emergency operations the skin is shaved dry and dehydrated with spirit, after which the iodine is applied as described above. The staining of the skin is an advantage, as it enables the operator to recognise the area that has been prepared.

If any acne pustules or infected sinuses are present, they should be destroyed or purified by means of the thermo-cautery or pure carbolic acid, after the patient is anaesthetised.

Appliances used at Operation.—Instruments that are not damaged by heat must be boiled in a fish-kettle or other suitable steriliser for fifteen minutes in a 1 per cent. solution of cresol or washing soda. Just before the operation begins they are removed in the tray of the steriliser and placed on a sterilised towel within reach of the surgeon or his assistant. Knives and instruments that are liable to be damaged by heat should be purified by being soaked in pure cresol for a few minutes, or in 1 in 20 carbolic for at least an hour.

Pads of Gauze sterilised by compressed circulating steam have almost entirely superseded marine sponges for operative purposes. To avoid the risk of leaving swabs in the peritoneal cavity, large square pads of gauze, to one corner of which a piece of strong tape about a foot long is securely stitched, should be employed. They should be removed from the caskets in which they are sterilised by means of sterilised forceps, and handed direct to the surgeon. The assistant who attends to the swabs should wear sterilised gloves.

Ligatures and Sutures.—To avoid the risk of implanting infective matter in a wound by means of the materials used for ligatures and sutures, great care must be taken in their preparation.

Catgut.—The following methods of preparing catgut have proved satisfactory: (1) The gut is soaked in juniper oil for at least a month; the juniper oil is then removed by ether and alcohol, and the gut preserved in 1 in 1000 solution of corrosive sublimate in alcohol (Kocher). (2) The gut is placed in a brass receiver and boiled for three-quarters of an hour in a solution consisting of 85 per cent. absolute alcohol, 10 per cent. water, and 5 per cent. carbolic acid, and is then stored in 90 per cent. alcohol. (3) Cladius recommends that the catgut, just as it is bought from the dealers, be loosely rolled on a spool, and then immersed in a solution of—iodine, 1 part; iodide of potassium, 1 part; distilled water, 100 parts. At the end of eight days it is ready for use. Moschcowitz has found that the tensile strength of catgut so prepared is increased if it is kept dry in a sterile vessel, instead of being left indefinitely in the iodine solution. If Salkindsohn's formula is used—tincture of iodine, 1 part; proof spirit, 15 parts—the gut can be kept permanently in the solution without becoming brittle. To avoid contamination from the hands, catgut should be removed from the bottle with aseptic forceps and passed direct to the surgeon. Any portion unused should be thrown away.

Silk is prepared by being soaked for twelve hours in ether, for other twelve in alcohol, and then boiled for ten minutes in 1 in 1000 sublimate solution. It is then wound on spools with purified hands protected by sterilised gloves, and kept in absolute alcohol. Before an operation the silk is again boiled for ten minutes in the same solution, and is used directly from this (Kocher). Linen thread is sterilised in the same way as silk.

Fishing-gut and silver wire, as well as the needles, should be boiled along with the instruments. Horse-hair and fishing-gut may be sterilised by prolonged immersion in 1 in 20 carbolic, or in the iodine solutions employed to sterilise catgut.

The field of operation is surrounded by sterilised towels, clipped to the edges of the wound, and securely fixed in position so that no contamination may take place from the surroundings.

The surgeon and his assistants, including the anaesthetist, wear overalls sterilised by steam. To avoid the risk of infection from dust, scurf, or drops of perspiration falling from the head, the surgeon and his assistants may wear sterilised cotton caps. To obviate the risk of infection taking place by drops of saliva projected from the mouth in talking or coughing in the vicinity of a wound, a simple mask may be worn.

The risk of infection from the air is now known to be very small, so long as there is no excess of floating dust. All sweeping, dusting, and disturbing of curtains, blinds, or furniture must therefore be avoided before or during an operation.

It has been shown that the presence of spectators increases the number of organisms in the atmosphere. In teaching clinics, therefore, the risk from air infection is greater than in private practice.

To facilitate primary union, all haemorrhage should be arrested, and the accumulation of fluid in the wound prevented. When much oozing is anticipated, a glass or rubber drainage-tube is inserted through a small opening specially made for the purpose. In aseptic wounds the tube may be removed in from twenty-four to forty-eight hours, and where it is important to avoid a scar, the opening should be closed with a Michel's clip; in infected wounds the tube must remain as long as the discharge continues.

The fascia and skin should be brought into accurate apposition by sutures. If any cavity exists in the deeper part of the wound it should be obliterated by buried sutures, or by so adjusting the dressing as to bring its walls into apposition.

If these precautions have been successful, the wound will heal under the original dressing, which need not be interfered with for from seven to ten days, according to the nature of the case.

Dressings.—Gauze, sterilised by heat, is almost universally employed for the dressing of wounds. Double cyanide gauze may be used in such regions as the neck, axilla, or groin, where complete sterilisation of the skin is difficult to attain, and where it is desirable to leave the dressing undisturbed for ten days or more. Iodoform or bismuth gauze is of special value for the packing of wounds treated by the open method.

One variety or another of wool, rendered absorbent by the extraction of its fat, and sterilised by heat, forms a part of almost every surgical dressing, and various antiseptic agents may be added to it. Of these, corrosive sublimate is the most generally used. Wood-wool dressings are more highly and more uniformly absorbent than cotton wools. As evaporation takes place through wool dressings, the discharge becomes dried, and so forms an unfavourable medium for bacterial growth.

Pads of sphagnum moss, sterilised by heat, are highly absorbent, and being economical are used when there is much discharge, and in cases where a leakage of urine has to be soaked up.

Means adopted to combat Infection.—As has already been indicated, the same antiseptic precautions are to be taken in dealing with infected as with aseptic wounds.

In recent injuries such as result from railway or machinery accidents, with bruising and crushing of the tissues and grinding of gross dirt into the wounds, the scissors must be freely used to remove the tissues that have been devitalised or impregnated with foreign material. Hair-covered parts should be shaved and the surrounding skin painted with iodine. Crushed and contaminated portions of bone should be chiselled away. Opinions differ as to the benefit derived from washing such wounds with chemical antiseptics, which are liable to devitalise the tissues with which they come in contact, and so render them less able to resist the action of any organisms that may remain in them. All are agreed, however, that free washing with normal salt solution is useful in mechanically cleansing the injured parts. Peroxide of hydrogen sprayed over such wounds is also beneficial in virtue of its oxidising properties. Efficient drainage must be provided, and stitches should be used sparingly, if at all.

The best way in which to treat such wounds is by the open method. This consists in packing the wound with iodoform or bismuth gauze, which is left in position as long as it adheres to the raw surface. The packing may be renewed at intervals until the wound is filled by granulations; or, in the course of a few days when it becomes evident that the infection has been overcome, secondary sutures may be introduced and the edges drawn together, provision being made at the ends for further packing or for drainage-tubes.

If earth or street dirt has entered the wound, the surface may with advantage be painted over with pure carbolic acid, as virulent organisms, such as those of tetanus or spreading gangrene, are liable to be present. Prophylactic injection of tetanus antitoxin may be indicated.



CHAPTER XIII

CONSTITUTIONAL EFFECTS OF INJURIES

SYNCOPE—SHOCK—COLLAPSE—FAT EMBOLISM—TRAUMATIC ASPHYXIA—DELIRIUM IN SURGICAL PATIENTS: Delirium in general; Delirium tremens; Traumatic delirium.

SYNCOPE, SHOCK, AND COLLAPSE

Syncope, shock, and collapse are clinical conditions which, although depending on different causes, bear a superficial resemblance to one another.

Syncope or Fainting.—Syncope is the result of a suddenly produced anaemia of the brain from temporary weakening or arrest of the heart's action. In surgical practice, this condition is usually observed in nervous persons who have been subjected to pain, as in the reduction of a dislocation or the incision of a whitlow; or in those who have rapidly lost a considerable quantity of blood. It may also follow the sudden withdrawal of fluid from a large cavity, as in tapping an abdomen for ascites, or withdrawing fluid from the pleural cavity. Syncope sometimes occurs also during the administration of a general anaesthetic, especially if there is a tendency to sickness and the patient is not completely under. During an operation the onset of syncope is often recognised by the cessation of oozing from the divided vessels before the general symptoms become manifest.

Clinical Features.—When a person is about to faint he feels giddy, has surging sounds in his ears, and haziness of vision; he yawns, becomes pale and sick, and a free flow of saliva takes place into the mouth. The pupils dilate; the pulse becomes small and almost imperceptible; the respirations shallow and hurried; consciousness gradually fades away, and he falls in a heap on the floor.

Sometimes vomiting ensues before the patient completely loses consciousness, and the muscular exertion entailed may ward off the actual faint. This is frequently seen in threatened syncopal attacks during chloroform administration.

Recovery begins in a few seconds, the patient sighing or gasping, or, it may be, vomiting; the strength of the pulse gradually increases, and consciousness slowly returns. In some cases, however, syncope is fatal.